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July 1997, Vol 10, No 2 1

JOI/USSACJOI/USSACN E W S L E T T E RNEWS FROM THE JOINT OCEANOGRAPHIC INSTITUTIONS/U.S. SCIENCE SUPPORT PROGRAM ASSOCIATED WITH THE OCEAN DRILLING PROGRAM • JULY 1997, Vol 10, No 2

JOIDES Resolution returns to the Southern Oceancontributed by Rainer Gersonde and David Hodell, ODP Leg 177 Co-chief Scientists

ntarctica and the adjacent Southern Ocean represent one of the most important components of Earth’s climatesystem, yet many questions remain about theregion’s paleoenvironmental evolution (e.g.,[Kennett and Barron, 1992]). The main stum-bling block in developing detailed paleo-climatic records from this area has been thedearth of high-quality sedimentary se-quences. This December, JOIDES Resolutionwill voyage poleward to drill in the southeastAtlantic (ODP Leg 177) and near the AntarcticPeninsula (Leg 178). Here we review theobjectives of Leg 177, which will take coresfrom six sites along a transect from 41° to53° S (Figure 1). This transect will span theAntarctic Circumpolar Current (ACC), a coldsurface water mass that rings Antarctica andcontains complex fronts and upwelling/downwelling cells. Because the sites havealso been selected along a bathymetrictransect, ranging from 2100 to 4600 m, theyintersect three deep and bottom watermasses: Circumpolar Deep Water (CPW),North Atlantic Deep Water (NADW) andAntarctic Bottom Water (AABW) (Figure 2).The sediments recovered during Leg 177 willenable us to study the paleoceanographichistory of the southeast Atlantic on a varietyof time scales, including long-term (105 to 106

yrs, Cenozoic), orbital (104 to 105 yrs,Milankovitch), and suborbital (102 to 103 yrs).

Long-term (Cenozoic) variability

The Antarctic cryosphere contains the largestaccumulation of ice on Earth. The develop-ment and evolution of the Antarctic ice sheetsand sea-ice field has had a profound influ-ence on global sea-level history, Earth’s heatbudget, atmospheric circulation, surface anddeep-water circulation, and the evolution ofAntarctic biota. Previous deep-sea drilling inthe Southern Ocean provides us with a basicunderstanding of the paleoceanographic and

paleoclimatic evolution of the southern highlatitudes during the Cenozoic, which isclosely related to paleogeographic changes(i.e., opening of Tasman Seaway and DrakePassage) that permitted the ACC to develop[Kennett, 1977]. Isotopic and microfossilevidence suggests that Antarctic ice sheetswere established and sea ice expanded duringthe earliest Oligocene, but little agreementexists on the presence of ice sheets during theEocene, particularly during the early-middleEocene. Prior to the growth of large NorthernHemisphere ice sheets during the late Plio-cene, the Southern Hemisphere cryosphere iswidely considered to have been a majordriving force for global climate and sea-levelfluctuations. There are significant differencesof opinion, however, regarding the details of

Fig. 1: Location of Leg 177 drilling targets and DSDP/ODP sites(shaded circles) in the South Atlantic relative to major hydrographicfronts. Primary targets are underlined.

A

INSIDE...4 Fellowship Profile:

Katharina Billups

5 Subsurface bio-sphere report

6 Marine coring atmargins report

10 Drill Bits

12 Announcements

14 Fluid flow throughoceanic crust

17 NSF Report: Planning fora new drilling program

18 Seismogenic zoneexperiment report

19 1997-98 DistinguishedLecturer Series hosts

20 ODP pubs: A letter fromBob Detrick, EXCOM Chair

22 A letter from the Chair:Making tough decisions

23 USSAC membership

Weddell Gyre/ACC-Boundary

Subantarctic Front

Polar Front 50°

40°

30° S0° 10° 20° 30°E10°W

Punta Arenas

Feb. 9, 1998

360361

526

704

TSO-7B, C

359

703

SubSAT-1B

SubSAT-3B

TSO-2B

TSO-4BTSO-3C

TSO-5C

depart Capetown

12/15/97

TSO-6A, B

Bouvet I.

SubSAT-4B

AFRICA

average winter sea ice edge

Subtropical Front

2 JOI/USSAC Newsletter

Rainer Gersonde is asenior researcher at the

Alfred WegenerInstitute for Polar and

Marine Research inBremerhaven, Germany.

He has been involvedsince 1983 in Antarcticresearch, and to date

has sailed on eightexpeditions to the

Southern Ocean withthe RV Polarstern; on

four of those cruises hewas chief scientist. Dr.Gersonde sailed with

ODP previously as adiatom biostratigrapher

on Leg 113.

David Hodell isProfessor of Geology at

the University ofFlorida, Gainesville. He

has participated in ODPLegs 114 and 162 as a

sedimentologist andinorganic geochemist,

respectively. He alsoserved on the JOIDES

Ocean History Paneland currently serves as

a member of the newOperations Committee

(OPCOM).

Antarctic cryospheric evolution, arising pri-marily from variations in the interpretation ofcontinental, marine isotope, and sea-levelrecords.

A key objective of Leg 177 will be to augmentthe paleoclimatic, paleoceanographic, biogeo-graphic, and biostratigraphic history of theSouthern Ocean during the Cenozoic, includ-ing the evolution and stability of the Antarcticcryosphere. We expect to recover sedimentsas old as Eocene in two deep holes (TSO-2B,TSO-6A). When combined with previouslydrilled sites, these holes will form a latitudinaltransect that spans the ACC and allows us tostudy the response of surface water massesin the Southern Ocean to the glacial evolutionof Antarctica. Reconstruction of latitudinalisotopic gradients and analysis of the biogeo-graphic distribution and abundance patternsof microfossil assemblages will improve ourunderstanding of the growth and stability ofthe ice sheets. Leg 177 will also further pale-ontological and chronostratigraphic objec-tives by improving southern high-latitudecalcareous and siliceous biozonations, and bycorrelating biostratigraphic events toorbitally-tuned time scales.

Orbital (Milankovitch) scale variability

One of the fundamental tasks in paleocean-ography is to reveal the phase relationshipsbetween climatic proxies from different

oceanographic regionsin order to understandthe mechanisms bywhich changes inorbital insolation haveforced glacial-to-interglacial climatechange during theNeogene. Imbrie et al.[1992] suggested anearly response ofsurface and deepwaters in the SouthernOcean relative to proxydata from other regions.This early response hasalso been observed byother studies during thelast climatic cycle[Charles et al., 1996;Bender et al., 1994],suggesting that theAntarctic region mayplay an important role

in driving climate change. The reason for thismay be linked to changes in the distributionof sea ice, a fast-responding variable in theclimate system. We will study the response ofthe Southern Ocean to orbital forcing and willdetermine the phase relationships to climaticchanges in other regions.

Leg 177 records will provide spatial andvertical transects needed to improve ourunderstanding of the Neogene response toorbital forcing of surface and deep waters andsea ice in the southern high latitudes. Thesites will span the range over which theoceanic fronts and the sea ice limits haveadvanced and retreated over time within theACC (Figure 1). We intend to study specifictime intervals that have not been well recov-ered by previous drilling in the SouthernOcean. For example, a particularly interestingtime period was the mid-Brunhes, especiallymarine isotope stage 11 (423 to 363 kyrs),when it appears that climate warmed greatly.This is indicated by a dramatic southwardshift of the Polar Front and by the depositionof carbonate microfossils in polar regions thatare normally dominated by siliceous plank-ton, which generally inhabit colder waters.Study of this interval is particularly timelynow that the Vostok ice core has beenextended to stage 11 [Petit et al., 1997]. Theability to correlate marine sediment recordsto ice cores significantly improves paleocli-mate reconstructions.

Fig. 2: Vertical distribution of potential temperature on a depth transect in the eastern Atlanticsector of the Southern Ocean relative to the Leg 177 drilling targets.

55°S53°51°49°47°45°43°41°Latitude

5

4

3

2

1

0

Dep

th (

km)

AgulhasRidge Meteor

Rise

BouvetIsland

Weddell Basin

TSO-2B

TSO-3C

TSO-4B

TSO-6A,B

TSO-7B,C

ODP703

ODP704

SubSAT-3B

SubSAT-4B,C

TSO-5C CircumAntarctic Siliceous Belt.

AABW

NADW

NADW

CDW

CDW

SubSAT-1B

Polar FrontSubantarctic Front

July 1997, Vol 10, No 2 3

Suborbital (millennial) scale variability

Another current focus of paleoclimaticresearch is the origin of millennial-scaleclimate variability that was first recognized inice cores, but now has been found globally[Broecker, 1997]. Correlation of Greenland ice-core records to those in sediment cores fromthe North Atlantic demonstrated that therapid climatic oscillations observed in icecores (Dansgaard/Oeschger events) are alsopreserved in marine records [Bond et al., 1993;Behl and Kennett, 1996]. One hypothesis forthe origin of these oscillations is based on thestrength of the ocean’s thermohaline con-veyor belt [Broecker, 1997]. The South Atlanticsector of the Southern Ocean is especiallyimportant in this regard because it representsthe entry point of NADW into the ACC. As aresult, the South Atlantic sector is highlysensitive to changes in the strength of theNADW conveyor. For example, Charles et al.[1996] reported millennial-scale variability inbenthic foraminiferal carbon isotopes in theSouthern Ocean that showed a behaviorsimilar to the climate of the North Atlantic(Figure 3). Furthermore, correlation betweenthe Greenland Summit ice core (GISP2) andthe Antarctic Vostok ice core suggest that thelonger-term millennial variations (circa 2 kyr)observed in GISP2 are manifest as changingtemperatures in the Antarctic ice core record[Bender et al., 1994].

ReferencesBehl, R.J. and J.P. Kennett, Brief Inter-

stadial Events in the Santa BarbaraBasin, NE Pacific, During the Past 60kyr, Nature, 379, 243-246, 1996.

Bender, M., T. Sowers, M. Dickson, J.Orchardo, P. Grootes, P. Mayewski,and D. Messe, Climate teleconnectionsbetween Greenland and Antarcticathroughout the last 100,000 years,Nature, 372, 663-666, 1994.

Bond, G., W. Broecker, S. Johnsen, J.McManus, L. Labeyrie, J. Jouzel, andG. Bonani, Correlations betweenclimate records from North Atlatnicsediments and Greenland ice, Nature.365, 143-147, 1993.

Broecker, W.S.,Will our ride into theGreenhouse future be a smooth one?GSA Today, 7, 1-6, 1997.

Charles, C.D., J. Lynch-Stieglitz, U.S.Ninnemann, and R.G. Fairbanks,Climate connections between thehemispheres revealed by deep-seasediment core/ice core correlations,Earth Planet. Sci. Letts., 142, 19-27,1996.

Imbrie, J., et al., On the structure andorigin of major glaciation cycles 1.Linear responses to Milankovitchforcing, Paleoceanography, 7, 701-738,1992.

Kennett, J.P., Cenozoic evolution ofAntarctic glaciation, the circum-Antarctic ocean, and their impact onglobal paleoceanography, J. Geophys.Res. 82, 3843-59, 1977.

Kennett, J.P., and J.A. Barron,Introduction to The AntarcticPaleoenvironment: A Perspective onGlobal Change, Antarctic ResearchSeries. 56, 1-6, 1992.

Petit, J.R., I. Basile, A. Leruyuet, D.Raynaud, C. Lorius, J. Jouzel, M.Stievenard, V.Y. Lipenkov, N.I. Barkov,B.B. Kudryashov, M. Davis, E.Saltzman, and V. Kotlyakov, Fourclimate cycles in Vostok ice core.Nature, 387, 359-360, 1997.

To study millennial-scale oscillations and thepotential link between the North Atlantic andSouthern Ocean, recovery of rapidly depos-ited, deep-sea sedimentary sequences isrequired. Two recent ODP legs in the NorthAtlantic (162 and 172) were highly successfulin recovering long sections from sedimentdrift deposits. To obtain complementaryrecords from the high-latitude SouthernHemisphere, we have targeted sediment driftsand the circumantarctic biogenic silica belt inthe South Atlantic. Several of the proposedsites (SubSAT-1B, TSO-6A,B, and TSO-7C,B)have average sedimentation rates exceeding20 cm/103 yrs, which will enablepaleoclimatic studies on millennial timescales. For example, SubSAT-1B is locatednear the site of piston core RC11-83, whichcontains strong evidence for millennial-scalevariability (Figure 3). We anticipate thatSubSAT-1B will extend this short piston corerecord well back into the early Pleistocene.

Summary

Leg 177 is expected to recover an invaluablearchive of cores needed to extend our under-standing of the Southern Ocean. Improvedrecovery of cores with high sedimentationrates will permit us to conduct detailedstudies of paleoclimate that were previouslyimpossible. We expect that Leg 177 will bethe first in a series of legs dedicated to drillingin various sectors of the Southern Oceanusing techniques that enable recovery ofcomplete sedimentary sections.

Fig. 3: (a) Benthic forami-niferal carbon isotopicrecord of Core RC11-83(located near SubSAT-1B[Charles et al., 1996])compared to (b) the oxygenisotopic record from theGreenland Summit ice core,(c) the Vostok ice coredeuterium record, and theoxygen isotopic recordsfrom planktic (d) andbenthic (e) foraminiferalspecies from RC11-83.

RC11

-83

("B"

)

Vostok: E. Antarctic Plateau

G. bulloides

N. pachyderma -500

-480

-440

1.0

1.5

2.0

2.5

3.0

0 10 20 30 40 50 60 70 80Age (kyr)

-42

SummitGreenland

-40

-38

-36

-34

-1.5

-1.0

-0.5

0.0

δ13C

(‰ to

PDB)

RC11-83benthic

δ18O

(‰ S

MO

W)

δD

(‰ SM

OW

)

-460

δ18O

(‰ t

o P

DB)

(a)(b)

(c)

(d)

(e)


T

Implications of thermohaline circulationfor early Pliocene climate change

KatharinaBillups

Ph.D. Student:UC Santa Cruz

Faculty Advisors:Ana Christina Ravelo

James C. Zachos

FellowshipProfile

Gs. sacculifer

N. dutertrei

-2.5

-2.0

-1.5

-1.0

-0.5

0.03.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8

δ18O

(‰

)

Age (Ma)

wo mechanisms have been invoked to explain high-latitude warmth of the early Pliocene, increased poleward heat trans-port and elevated atmospheric CO2 levels.These mechanisms can only be tested byreconstructing the relative strength of ther-mohaline overturn and the degree of tropicalsea surface temperature (SSTs) changes. Tothis end, I have developed benthic andplanktonic stable isotope stratigraphiesdrilled along a depth transect on Ceara Risein the western equatorial Atlantic (ODP Leg154, Sites 925 and 929), and am in theprocess of generating comparable planktonicstable isotope stratigraphies from the westernequatorial Pacific (ODP Leg 130). My intent isto use the Pacific records to assess the heattransport component with respect to globalclimate variability in the Atlantic surfacerecords.

Reconstructions of deep and surface waterhydrography based on the Ceara Rise isotoperecords indicate that early Pliocene thermo-haline circulation was at least comparable totoday. Benthic carbon isotope gradients alongCeara Rise are similar to modern, suggestingsimilar vertical deep-water mass distributionsand hence a relatively strong flux of Northern

Component Deep-Water [Billups et al., inpress]. Planktonic oxygen isotope resultsillustrate that the surface dwellingGlobigerinoides sacculifer recorded δ18O valueshigher than late Holocene, while the ther-mocline species Neogloboquadrina dutertreirecorded values lower than late Holocene(Figure 1). Only the N. dutertrei δ18O valuesagree with lower mean oceanic δ18O valuesdue to reduced early Pliocene ice-volume. Iinterpret the relatively high Gs. sacculifer δ18Ovalues as cooler sea surface temperatures (2-3° C) consistent with relatively strong warmwater advection away from the equatorialregion. I conclude that a relatively strongthermohaline cell may at least in part explainearly Pliocene warmth. Work in progress nowcomprises completion of planktonic stableisotope records in western equatorial Pacificto separate planktonic stable isotope variabil-ity due to local hydrography from globalclimate change.

References:Billups, K., A.C. Ravelo, and J.C. Zachos, Early Pliocene deep-water circulation:

Stable isotope evidence for enhanced northern component deep-water. InCurry, W.B., N.J. Shackleton, C. Richter, et al., Proc. ODP, Sci. Results, 154, inpress.

Billups, K. and H.J. Spero, Reconstructing the stable isotope geochemistry andpaleotemperatures of the equatorial Atlantic during the last 150,000 years:Results from individual foraminifera, Paleoceanography, 11, 217-238, 1996.

Figure 1: Planktonic (Globigerinoides sacculifer, solid line; Neogloboqudrina dutertrei, dashed line) oxygenisotope records from Site 925 on Ceara Rise, ODP Leg 154. The horizontal lines represent late Holocenemeasurements from a nearby core [Billups and Spero, 1996]. Gs. sacculifer δ18O values are on average 0.3-0.4 ‰ higher than late Holocene, while N. dutertrei δ18O values are 0.2-0.3 ‰ lower. Only the N. dutertrei δ18Ovalues agree with lower mean oceanic δ18O values due to reduced early Pliocene ice-volume. I interpret therelatively high Gs. sacculifer δ18O values as cooler sea surface temperatures (2-3°C) consistent with relativelystrong warm water advection away from the equatorial region.

July 1997, Vol 10, No 2 5

A

Contributed by Kim Juniper, Marvin Lilley, and John Baross

Workshop on the subsurface biosphere at mid-ocean ridges WorkshopReport

This workshop was heldMarch 17-19, 1997 inWashington, DC and wassponsored by the RIDGEProgram, JOI/USSSP, NOAAVENTS Program, and theUniversity of WashingtonVolcano Center.

Kim Juniper is at GEOTOP,Université du Quebec àMontréal.

Marvin Lilley is AssociateProfessor at the School ofOceanography, Universityof Washington.

John Baross is Professor atthe School of Oceanogra-phy, University of Washing-ton.

workshop was held in Washington, DC from 17-19 March 1997 to examine the evidence for a subsurface bio-sphere associated with mid-ocean ridges andto identify the key questions that need to beaddressed in order to test the existence of aspatially extensive biosphere that is notdependent on nutrients derived from photo-synthesis. More than 100 microbiologists,biologists, geologists, geophysicists,geochemists, biochemists, biotechnologistsand engineers attended the workshop. Be-cause of the large group and diversity oftopics, the format of the meeting consisted ofinvited talks and panel discussions on broadranging topics, as well as contributed posters.The talks and panel discussions focused onthe physical, geophysical and geochemicalcharacteristics of the subsurface, the micro-bial diversity and biogeochemistry issues, andresearch strategies for sampling and modelingthe subsurface.

A diverse body of recent evidence supportsthe idea of a subsurface microbial biosphereassociated with mid-ocean ridges. Thisincludes the detection of microorganisms indrill cores from deep ocean sediments ob-tained through the Ocean Drilling Program(ODP), the isolation of hyperthermophilesfrom deep oil wells and diffuse flow fluidsfrom new eruption sites, and the detection ofmicroorganisms in basaltic glass. Many of thetalks and panel discussions focused on thegeophysical and geochemical characteristicsof these environments and the sources andkinds of carbon, nitrogen, phosphorus, andelectron acceptors and donors that would beavailable to support a microbial community.Some of the highlights of the invited talksincluded: 1) seismic evidence pointing toactive cracking and consequently hydrother-mal circulation to depths of 5 km along theEndeavour Segment in the NE Pacific Ocean;2) high porosity of the extrusive layer at mid-ocean ridges; 3) the presence of microorgan-isms in deep-sea cores that might haveextremely slow reproduction rates; 4) thepossibility that iron may be the most impor-tant electron acceptor and donor for subsea-

floor bacteria; 5) models for abiotic synthesisof organic compounds under hydrothermalconditions; 6) the possibility that new deep-sea eruption events eject deep subsurfacemicroorganisms; and 7) the implications of asubsurface biosphere associated with hydro-thermal activity to life on other planets andmoons and to the origin and early evolutionof life on Earth. The lively panel discussionsfocused on subsurface spatial dimensions, thesources and kinds of carbon and othernutrients needed to support life in the subsur-face, and the diversity of microorganisms thatcould exploit these available nutrients.

It was clear from this workshop that manyquestions exist regarding the physical,chemical and biological nature of the subsur-face habitat and that answers to thesequestions will require interdisciplinarymeasurements, experiments and models.Some of the key issues to be resolved whichwere identified at the workshop include:1) the vertical and horizontal dimensions ofthe subsurface biosphere; 2) the importanceof hydrothermal circulation to the subsurfacemicrobial community; 3) the sources andkinds of carbon, nitrogen, phosphorus andenergy sources for subsurface microbialcommunities; 4) whether or not new eruptiveevents, including diking episodes, releaseindigenous subsurface microorganisms;5) how microorganisms affect the geochemis-try of the subsurface; 6) the phylogenetic andphysiological diversity of subsurface micro-bial communities; and 7) the fate of subsur-face microbial carbon. The workshop alsoconcluded that rapid response to new sea-floor eruptions, time series measurements,and drilling were among the importantapproaches needed to facilitate further studyof the issues listed above.

One of the most rewarding aspects of theworkshop was that so many insightful andenthusiastic researchers turned their atten-tion to this subject and promising newcollaborations were born.


workshop to foster dialogue between scientific users and technical providers of shallow-water (<500 m) coringand logging at margins was held May 1 and 2at Lamont-Doherty Earth Observatory. A totalof 28 scientists and 6 representatives from 4offshore engineering companies attended.This article summarizes workshop findingswith the hope that it will help to stimulatescientific exploration into the rich archives ofmargin sediments.

Science at margins

Scientific breakthroughs await those who canlog and core with complete recovery tens tohundreds of meters into shallow watersediments in siliciclastic and carbonatesettings, on margins passive or active, onplatforms or deltas. Participants outlinedseveral scientific payoffs that can be antici-pated: understanding what controls thepreservation of short-lived “events” in thegeologic record; detailed analyses of pre- andpost-failure gravity slides; verification offacies models framed by sequence architec-ture and the influence of relative sea-levelchanges; detailed histories of carbonateevolution and sorting out the many factorsthat affect these systems; paleoceanographyin shallow-water settings; and eustatichistory. Complete core recovery — especiallyacross centimeter-scale stratal discontinuities— accompanied by in situ physical measure-ments are critically important to all of thesemissions. Several participants noted that thequality of acoustic surveys has greatlysurpassed our ability to ground-truth thesedata and the geologic inferences drawn fromthem; all agreed that it is now time to catchup with subbottom sampling at depth scalescomparable with these acoustic images.Sampling plans must be global in scope, butlocally must allow scientific objectives togovern precise sample location andsubbottom depth. The modern shoreline is anarbitrary line dividing the techniques forreaching the subsurface objectives, and wemust not forget that scientific rewards canalso be found in coastal plain sediments thatonce were submarine.

Technology at margins

Contractors at the workshop describedvarious shallow-water sediments samplingtechniques. Three general approaches werepresented: vibra-coring, push/percussive/rotary coring, and in situ geotechnical moni-toring without coring (Table 1). Vibracoring isaccomplished by using a cable to lower acorepipe to the seabed and vibrating it intothe sediment with a submerged motor. Thepipe and motor assembly is vertically stabi-lized in one of several ways, and is deployedand retrieved for each core. This technique isweather-sensitive during launch and recoveryfrom a floating vessel, and while usuallyaccomplished from a crane or movable frameover the side, can also be done through aship’s more protected center well, if available.Vibracores can be acquired in virtually anynear shore setting, even where it is impracti-cal to work from a floating platform. Thedeep-water limit is determined by shipstability and by the type of vibrating motor:pneumatic and hydraulic systems are practi-cal to about 75 m water depth, while electricsystems can continue to 750 and perhaps to1500 m. Depth of penetration and degree ofcore disturbance are controlled in part by thefrequency and amplitude of the appliedvibrations. Core penetration and quality canbe severely limited by thick sand or especiallystiff clay. If there is a soft-sediment, fine-grained target below a difficult horizon,techniques can be used to wash down with-out sampling and resume core recovery whenfeasible. Nonetheless, practical penetrationsfor all types of existing vibracores are in therange of 10-20 m subbottom.

Push/percussive/rotary coring spans a largerange of operating settings and costs. Thebasic approach applies a constant load orpercussive impulse from above the seasurface that drives a core pipe into thesediment. With increasing induration, opera-tions switch to a top-drive motor that rotatesa drill bit and cuts into the formation. Withincreasing sea state, water depth, and desireddepth of penetration, progressively morerobust systems can be used to reach thou-

Contributed by Gregory Mountain

MarineCAM: A workshop on marine coring at marginsWorkshopReport

AThis workshop was

co-sponsored by JOI/USSSP and the Office of

Naval Research.

Gregory Mountain is aSenior Research Scientist at

Lamont-Doherty EarthObservatory of Columbia

University. Obtaining coresat margins to determine

the history and effect ofsea-level change has been

an elusive goal of his formany years. He estimates

that between his firstparticipation on a drillingexpedition offshore NewJersey (DSDP Leg 95) and

subsequent ODP Legs 150and 174A, sea level has

risen 28 mm. He’s anxiousto finish the job before the

water gets any deeper.

July 1997, Vol 10, No 2 7

sands of meters below seafloor (mbsf) inhundreds of meters of water. Several sam-pling techniques are available (Table 2). Thelow end of push/percussive/rotary coringbegins with a lightweight system typicallyoperated from an anchored platform thatbecause of its weather sensitivity, contractorsadvised is not usable in more than 30 mwater depths. Depending on the substrate,samples can be recovered to 30 m subsea-floor. A modular, portable barge system canbe assembled on-site; its operating depth islimited by weather sensitivity, and its seafloorpenetration is limited by the size/buoyancy ofthe barge. Typical estimates are up to 30 mwater depth and 100 m penetration. In-

creased seaworthiness and mobility makeships more versatile platforms than floatingbarges. Mid-sized, anchored vessels withcoring through a center well can recoversamples to 650 mbsf in as much as 300 mwater depths. For more ambitious goals, adynamically positioned ship can increase theoperating water depths to 700 m, again withsamples to 650 mbsf. A jack-up platform canbe used instead of a ship to lower legs to theseafloor, raise the platform out of the water,and isolate the drill rig from wave motion.These platforms begin with small, towedbarges that are recommended in 6-20 mwater depths; they can hang enough pipe tocore to 500-1000 mbsf. Larger, self-propelled

DOWNHOLE DEVICE TYPICAL PLATFORM WD, M MBSF COMMENTS ~COSTS6,7

pneumatic vibracorer mid-size ship of opportunity 0-75 101,2 4 - 8

electric vibracorer mid-size ship of opportunity 0-1500 101 4 - 8

lt-wt electric vibracorer small ship of opportunity 0-5000 101 Rosscore 2 - 6

lt-wt push/percuss/rot corer small portable barge 5-30 301 Rosscore; extreme w’ther sensitive 4 - 6

push/percuss/rotary corer portable barge5? 6-30 100 very w’ther sensitive; 15 / 250 / 500a

mbsf limited by barge buoyancy

“ self-elevating barge 6-100 ?1000+ up/down ops very w’ther sens. 30 / 1,200 / 2,000b

“ oil field jack-up 20-100 ?1000+ “ >> ? 1,000 total

“ anch’d mid-sized ship w/ pool5 6-100 6503 e.g. Fugro Failing 2000 system4 30 / 500 / 1,000b

“ DP ship5 100+ 6503 e.g. M/V Bucentaur/Norskald4 75 / 1,000 / NAb,c

“ oil field semi-submersible5? 100+ ?1,000+ ? 100 + / ? / ?

Terrabor rotary corer mid-size ship w/ pool 500 50-100 under development; no wireline ?or over-the-side logs; limited heave comp

geotech measurement anch’d mid-sized ship w/ pool5 6-100 701 no samples 30 / 500 / 1,000b

“ DP ship w/ pool5 100+ 701 e.g. M/V Bucentaur; no samples 75 / 1,000 / NAb,c

Table 1: MarineCAM options

1 limited by stiff clays + thick sands2 “could be increased to 50 mbsf or more” - K. Moran3 Fugro’s Failing 2000 rig + Bucentaur deployable to 650 mbsl (not mbsf)4 ? Failing systems + Bucentaur/Norskald can take only push/piston cores (no hard rock diamond core barrel)5 need seafloor reaction mass

6 $K/day vibra-coring includes mob/demob, ~3-6 cores/day7 wireline based on 100 mbsf, 30 days on site:

a $K/day not incl mob from east coast U.S. / $K east coast U.S. ops / $K west coast U.S. opsb $K/day not incl mob from Gulf of Mexico / $K east coast U.S. ops / $K west coast U.S. opsc west coast U.S. ops only if ship available from SE Asia or China


jack-up barges can work to 100 m and coreto 1000 mbsf. Oil field jack-ups complete thisgroup of platforms, operating in water depthsup to 100 m and penetrating to well over1000 m. Regardless of size, however, all jack-ups are uniquely weather sensitive duringjack-up and jack-down operations.

The Terrabore system is a variation of theabove coring technique currently underdevelopment by a consortium of Norwegiancompanies. It is adapted from mining technol-ogy and is under review by Antostrat forpossible use in overconsolidated glacial tillsalong the Antarctic continental margin. Ituses rotary coring only, is planned for de-ployment from mid-sized ships of opportunityeither over the side or through a center well,and is intended for operating in 500 m ofwater and to 50-100 mbsf. Thus far, however,and in contrast to the available technologiesdescribed previously, Terrabore has limitedheave compensation, a function that is vitallyimportant to maximizing core recovery/quality. In further contrast to existing sys-tems, Terrabore at present has no capacity toacquire in situ measurements via wirelinelogs.

The third technique described by contractorsis a suite of measurements that yield in situsediment properties but do not recoversamples (Table 3). These tools record any ofseveral engineering properties typically usedto determine bearing load capacity beforeplacing structures directly on the seafloor.Because of the cm-scale resolution, highreliability, and downhole continuity of thesedata, workshop participants agreed thisinformation could be a valuable asset to

push/percussive/rotary coring. The toolsdiscussed were cone penetrometers, vaneshear devices, pressuremeters, and packers.Measurements can be performed in undis-turbed sediment 3 m or less ahead of thebottom hole assembly while either continu-ously pushing the device into the seabed, orin a “measure - advance - measure” mode.Data are stored downhole and downloaded toa top-side computer when the tool is re-trieved. Typical properties extracted fromthese measurements include pore pressure,permeability, shear strength, stress history,and proxies for sediment density and compo-sition. These devices can be used to 3000 mwater depths or more. Their subbottomwindow of applicability is determined bysediment induration; typical applications to70 mbsf were described. Each can be de-ployed from the same platform that acquirespush/percussive/rotary cores, i.e., a floatingbarge, ship, or jack-up. Whatever the plat-form, however, a seafloor “reaction mass” isneeded to stabilize the bottom assembly andas much as possible isolate it from platformmotion at sea level.

The future at margins

Wide-ranging discussions followed thesefactual presentations: who will collect cores;when will they do this; and how will it bedone? Oil and gas exploration is currentlymoving into deeper water, providing both ahelp and a hindrance to scientific concerns.On the positive side, considerable informationis being gathered, that if made available,could address many basic scientific issues.The downside, however, is that with suchhigh demand for these technologies, opera-tional costs are high (Table 1).

Table 2: Rotary wireline sampling tools

TOOL LENGTH, M SED TYPE APPLICATION COMMENTS

split spoon ~1 sand grain size, composition, paleo very disturbed sample

Shelby tube ~1 soft to very stiff phys props, sedimentology, paleo, sample pushed ahead(a.k.a. push sampler) fine-grained sed pore water, bulk chem, paleomag of drill bit

piston sampler 1 - 3 all sed types same as above needs sf reaction mass;piston offsets wallfriction during push

diamond core 1.5 - 3 very stiff seds to sed same as above + petrology rotation cuts samplebarrel rocks to hard rocks

July 1997, Vol 10, No 2 9

Scientific groups mentioned during theworkshop that are likely to pursue efforts forcoring at margins included ODP, Antostrat,Strataform, Margins, and Images. ODPattempted its first coring in less than 100 m ofwater during Leg 174A this summer.Antostrat anticipates a round of pilot studycoring efforts off Antarctica in austral sum-mer ’98. Strataform is likely to pursue anambitious vibracoring program offshorenorthern California in summer ’98. Imagescontinues to sponsor long piston coring intodeep marine sediments, and there is interestin collecting comparable lengths of shallowmarine sediments as well. The relativelyaffordable costs and the large variety ofappropriate platforms ensure that vibracoringis within reach of expected scientific budgets.Furthermore, pre-site characterization neededfor 10-20 m penetrations are far more modestthan for deeper sampling operations.

The jump in cost and operational complexitybetween vibracoring and push coring poses asignificant challenge to meeting a variety ofscientific goals. The only route to >20 mbsfsamples discussed at the workshop is to hirespecialized companies. Daily costs begin at$15K and continue upward to more than$100K (Table 1). Contractors estimated thatmobilization costs for these platforms de-ployed to either the East or West coast of the

U.S. would range from $250K to $2M. Obvi-ously, every effort will be needed to reducethese costs by either sharing mobilizationwith other interests, waiting for a ‘platform ofopportunity’ that is transiting through a givenstudy area, or defining scientific programsthat are in areas close to where these plat-forms are already deployed. For any of thesestrategies to work, the research communityneeds to be in close communication withplatform operators, and at present thereseems to be no structure for maintaining suchcontact.

ODP was mentioned as an organization likelyto provide managerial benefit to coring atmargins. For example, a Program PlanningGroup could help to: a) formulate precisescientific objectives; b) maintain a schedule ofplatforms of opportunity; c) justify the use ofthe JOIDES Site Survey and Pollution Preven-tion and Safety Panels for pre-coring siteevaluation; and d) ensure proper sampledistribution and archiving at one of the ODPcore repositories.

Participants left the workshop with renewedconfidence that the time had come for coordi-nated coring at margins. The potential re-wards in this virtually untapped geologicarchive are very large, but so are the costs forreaching those goals.

Table 3: Rotary in situ wireline tools

TOOL APPLICATION COMMENTS

cone penetrometer cont stratig, proxy density, proxy sed type, shear can be done from wireline or from(CPT, PCPT, seismic) strength, dynamic pore press, pore press decay, autonomous seafloor unit

stress hist, velocity, optical (under devel) (e.g. Seascout, TSP, and others)

vane shear undrained shear strength, sensitivity, stress-strain

pressuremeter shear modulus, stress-strain, lateral stress, shear strength

packer permeability, hydraulic fracturing, flow test

temperature probe geothermal gradient, bottom water thermal history

logging-while-drilling proxy density, -porosity, -grain size, stratigraphy uncertain fit with pipe diameter;no sonic vel >> 2 km/sec, andeven then not generally available


Drill Bits CONCORDThe International CONference on CooperativeOcean Riser Drilling (CONCORD) was heldJuly 22-24 in Tokyo, Japan. Approximately150 scientists attended, including more than30 from the United States. CONCORD consid-ered a diverse range of topics for riser-supported drilling, from sampling the deepbiosphere to studying the deep architecture ofcontinental margins and the oceanic lithos-phere. CONCORD agreed that riser drillingwas “indispensable for the continual develop-ment of humankind’s understanding of thedynamic processes that shape our planet’ssurface.” Conference participants also de-cided that the first major goal for the newriser-equipped drillship, to be designed andbuilt by the Japanese Marine Science andTechnology Agency (JAMSTEC) in the earlyyears of the 21st century, should be a sys-tematic study of a seismogenic zone withinan active subduction system, probably in thewestern Pacific. Recommendations from theCONCORD report will form the fundamentalbasis for JAMSTEC’s proposal to Japanesegovernment funding sources later this year.

... J. Austin, UT Austin

Staff changes at ODP/TAMUThe ODP at Texas A&M University is pleasedto announce three new appointments in theScience Services department:

Dr. Tom Davies, formerly Associate Director ofThe University of Texas Institute for Geo-physics, is the new Manager of ScienceServices. Tom has served in various positionswith the ODP, including Program Associatefor the Ocean Drilling Program at NSF, asChief Scientist at JOI for the Ocean MarginDrilling Program, and as one of the foundingarchitects of USSSP. Tom also has an estab-lished record of scholarship, service to thecommunity, and has continued to be involvedwith ocean drilling since the DSDP. One ofTom’s duties is shipboard staffing, so if youare interested in participating on a leg,contact Tom at [email protected].

Dr. John Firth has been named ODP Curatorand reports to Tom Davies. John sailed as ashipboard participant on Leg 105, and joinedODP/TAMU in 1989 as a staff scientist.Questions regarding core sampling should bedirected to John at [email protected].

Mr. Brad Julson is the new Supervisor ofTechnical Support. Brad has served manyyears as a lab officer and technician datingback to the DSDP. With Brad’s appointment,applications are now being accepted at ODP/TAMU for a lab officer position.

... A. Woods, ODP/TAMU

Janus project sets sailJanus project members* are currently sailingon Leg 174B in a concerted effort to completesome key tasks of the first development phaseof the new computer database system and toset the stage for phase two. This phase willprimarily focus on incorporating digitalphotographic images of cores into the visualcore description applications. The Janussystem, which has been up and runningsuccessfully since Leg 171B, thanks to thededicated and hard work of Tracor andTAMU personnel, is maturing with use. Smallbugs are being worked out, users are becom-ing more familiar with the database, and thebenefits of a relational database are beingrealized. The specific tasks for the projectmembers on Leg 174B are to:

1) evaluate and make recommendations onnew visual core description (VCD) applica-tions, based on Applecorec, to accuratelycharacterize soft rocks, hard rocks, andstructural features. Efforts will includecompleting standard lithologies anddeveloping VCD output for publication;

2) evaluate the new age model function thatwill be used to assign ages to depthintervals;

3) review all existing applications (for ex-ample, those designed for the multi-sensing track, physical properties, andchemistry) for database editing needs,ease of use, and interface design, amongother things;

4) review current procedures for accessinglogging data;

5) evaluate designs of the user-interfaces foruploading data from the paleomagneticslab, the color reflectance instrument,Adara and WSTP tools (temperature data),and the Tensor tool (core orientationdata);

6) review web-based access to Janus;7) develop user requirements for a Janus link

to site survey and other seismic data;

... J. Farrell, JOI

JANUS STEERINGCOMMITTEE*

Kate Moran (Chair)Eve ArnoldSteve Hurst

SUBCONTRACTORS:Glenn CorserPaul AlbrightMike Ranger

LIAISONS:Jack FosterJohn Farrell

July 1997, Vol 10, No 2 11

Public affairs report“Blast From the Past”

The Smithsonian’s National Museum ofNatural History in Washington, D.C. is nowhighlighting a sediment core from ODP Leg171B in an exhibit called “Blast From thePast.” The exhibit, which will be on displaythrough February 1998 in the Dinosaur Hall,provides dramatic support for the long-standing theory that a large meteorite struckMexico’s Yucatan Peninsula 65 million yearsago causing the mass extinction at theCretaceous/Tertiary (K/T) boundary. Asmentioned in the March newsletter, the corewas recovered in 130 m of water about 350miles off the northern Florida coast andprovides an extraordinary record of themeteorite’s impact and resultant debris thatwas blasted into the atmosphere. This eventled to the extinction of about 70 percent of allspecies, including the dinosaurs. The ODPcore also contains a beautiful record of globalrepopulation of microorganisms in the oceansafter this event.

The exhibit also highlights the research ofDr. Brian Huber, a micropaleontologist in themuseum’s Department of Paleobiology, and amember of the Leg 171B expedition. Brianstudies foraminifera, single-celled organismsthat have lived in marine environments formore than 500 million years. More than 90percent of the free-floating foraminiferaspecies found in the Cretaceous chalk becameextinct at the K/T boundary. These speciesare larger, and far more diverse and ornate,than those found in the overlaying Tertiarylayer.

Leg 173 and the Halifax port call

Scientists continue to attract media interestbecause of recent public affairs activities. Leg173 petrologist Dr. James Beard, Curator ofEarth Sciences at the Virginia Museum ofNatural History, responded to questions fromindividuals logging onto the museum’s homepage in collaboration with the ODP. Morethan 200 questions were sent to the ship andanswered by Dr. Beard, who was also inter-viewed for an article in the Richmond Times-Dispatch (Richmond, VA).

At the Halifax port call, several news agenciesinterviewed ODP scientists. Articles appearedin two Halifax newspapers (the ChronicleHerald and Daily News). A local television

show in Halifax, Breakfast and Television,broadcasted their program “live” from theship while in port. Several people wereinterviewed during the broadcast, includingDrs. Jamie Austin, John Farrell, and KateMoran, Captain Ribbens, Erik Moortgate, andAaron Woods.

Leg 174A and the New York port call

On Sunday, July 20th, over 400 members andfriends of the Ocean Drilling Program scien-tific community participated in the JOI/USSSP-sponsored “Open Ship Day” in NewYork City during the JOIDES Resolution portcall. Visitors from as far away as Virginia andMassachusetts began the day by hearingscientific presentations by Drs. SusanHumphris (WHOI), Jamie Austin (UTIG), NickChristie-Blick (LDEO), and Peter deMenocal(LDEO). After browsing through several ODP-related displays, visitors toured JOIDESResolution where they also enjoyed brunch. Incooperation with LDEO/BRG, Schlumbergerproduced a dynamic display highlightinglogging technology. The event provided agreat opportunity for scientists, families, andstudents to see firsthand the capabilities ofJOIDES Resolution.

The New Jersey Margin leg and JOIDESResolution’s port call in New York generated agreat deal of media interest. Several print andradio journalists, television crews from NHK(Japan) and BBC (UK), and a freelance jour-nalist for CBS TeleNoticias (Miami) boardedthe ship during Leg 174A operations to collectfilm footage for upcoming documentaries andnews segments. To date, articles and storieshave been featured in The New York Times,USA Today, The Washington Post, AssociatedPress news wire, and National Public Radio.During the port call, media were invited tovisit JOIDES Resolution and interview scientistson Saturday, July 19. The CBS TV affiliate inNew York City broadcasted a story the sameevening and other television and print mediahave ODP stories scheduled for the future.

... P. Baker-Masson and J. Ramarui, JOI,and A. Woods, ODP/TAMU


A N N O U NN N O U NA

Warm Climate IntervalsWorkshop Report

S

JOI/USSAC is seeking graduate students of unusual promise andability who are enrolled in U.S. institutions to conduct researchcompatible with that of the Ocean Drilling Program. Both one-and two-year fellowships are available. The award is $22,000 peryear to be used for stipend, tuition, benefits, research costs, andincidental travel, if any. Masters and doctoral degree candidatesare encouraged to propose innovative and imaginative projects.Research may be directed toward the objectives of a specific leg orto broader themes.

PROPOSAL DEADLINEShorebased Work (regardless of leg): 11/15/97

For more information and/or to receive an application packetplease contact Andrea Johnson at:

JOI/USSAC Ocean Drilling Fellowship ProgramJoint Oceanographic Institutions1755 Massachusetts Ave., NW, Suite 800Washington, DC 20036-2102Tel: (202) 232-3900 x213Fax: (202) 232-8203E-mail: [email protected]

F E L L O W S H I P P R O G R A MJ O I / U S S A C O C E A N D R I L L I N G

One-year, shorebased fellowships

Stephen Schellenberg, University of Southern California“Geochemical and faunal analyses of deep-ocean ostracodes during twotransient climate extrema of the Paleogene: A test of benthic foram δ18O-based climate reconstructions using ostracode Mg:Ca ratios”

Michael Helgerud, Stanford University“Experimental measurement and theoretical modeling of the physicalproperties of sediments containing gas hydrates”

THE U.S. COMMITTEETO CONSIDER POST-2003

SCIENTIFIC OCEAN DRILLING

Convened by theJOI/U.S. Science Advisory Committee

in March 1997

The COMPOST-II report of is now available online. To view ordownload a copy of the report please visit the JOI web site atwww.joi-odp.org/joi/usssp/compost2.html.

OCEAN LITHOSPHERETHE

&

INTO THE 21ST CENTURYSCIENTIFIC OCEAN DRILLING

WOODS HOLE, MA, 26-28 MAY 1996

CONVENORS: Henry Dick (WHOI) & Catherine Mével (CNRS, Paris)

WORKSHOP SPONSORS: IAVCEI, InterRidge, ODP, JOI/USSSSP

The report of this workshop is now available on the JOI web site atwww.joi-odp.org/joi/usssp/lithosreport.html.

COM

POST

-II

USSAC would like to encourage individuals, or groups of individuals,to propose ODP results symposia, which culminate in a set of peer-reviewed manuscripts published by a scientific journal. Eachsymposium should pull together reseach from several ODP legs thatare linked by a common scientific objective. USSAC would considersupporting limited editorial assistance for the convenor(s) inaddition to travel for U.S. participants to attend the symposium. Formore information, contact Ellen Kappel at [email protected] or202-232-3900 ext. 216.

MARINE ASPECTS OF EARTH SYSTEM HISTORY (MESH)

Printed copies of the MESH report are now available from JOI.To receive a copy, please send a request to:

JOI/USSSPJoint Oceanographic Institutions1755 Massachusetts Avenue, NW, Suite 800Washington, DC 20036-2102Phone: (202) 232-3900Fax: (202) 232-8203E-mail: [email protected]

S ymposia on ODP results

JOI/USSAC OCEAN DRILLING FELLOWSS p r i n g / s u m m e r 1 9 9 7

Warm Climate IntervalsWorkshop Report

July 1997, Vol 10, No 2 13

C E M E N T SC E M E N T S

LEG 174A: New Jersey ShelfU.S. Co-Chief: J. Austin, UTIGU.S. Co-Chief: N. Christie-Blick, LDEOODP Staff Scientist: M. MaloneLDEO Logging Scientist: C. PirmezLDEO Logging Scientist: C. MajorG. Claypool, IndependentJ. Damuth, UT ArlingtonJ. Dickens, U of MichiganP. Flemings, Penn State UC. Fulthorpe, UTIGL. Giosan, SUNY Stony BrookM. Katz, LDEOC. McHugh, Queens College (CUNY)G. Mountain, LDEOH. Olson, UTIGC. Savrda, Auburn UL. Sohl, LDEOW. Wei, SIOB. Whiting, College of William & Mary

JOI/USSSP SUPPORTED SHIPBOARD PARTICIPANTS

Leg Region Co-Chiefs Dep. Port Date

174B CORK/ Becker New York 7/97Engineering Pettigrew

175 Benguela Berger Las Palmas 8/97Current Wefer

176 Return to 735B Dick Cape Town 10/97Natland

177 S. Ocean Gersonde Cape Town 12/97Paleocean. Hodell

178 Antarctic Barker Punta 2/98Peninsula Camerlenghi Arenas

179 NERO/Hammer Casey Cape Town 4/98Drilling

180 Woodlark Taylor Singapore 6/98Basin Huchon

181 SW Pacific Carter Townsville 8/98Gateway McCave

182 Great Feary Wellington 10/98Australian HineBight

183 Kerguelen Coffin Freemantle 12/98Plateau Frey

Scientific Objectives

To install a borehole seal (CORK) at Hole 395A and to conduct engineering tests.

To reconstruct the history of the Benguela Current and coastal upwelling of the regionbetween 5° and 32° S.

To deepen hole 735B and investigate the nature of magmatic, hydrothermal, andtectonic processes in the lower ocean crust at a slow-spreading ocean ridge.

To investigate the Cenozoic and Neogene paleoceanographic and climatic history ofthe southern high latitudes.

To explore Antarctic glacial history and sea-level change and to investigate thepaleoproductivity in the Antarctic coastal ocean.

To install a broadband ocean seismometer and instrument package which will fill agap in the Global Seismic Network and permit study of Indian Plate dynamics.

To investigate lithosphere extension, specifically the nature of low-angle faulting,continental breakup, and the evolution of conjugate rifted margins.

To reconstruct the stratigraphy, paleohydrology, and dynamics of the Pacific’s DeepWestern Boundary Current and related water masses since the early Miocene.

To document this carbonate platform’s evolution since 65 Ma in response to oceano-graphic and biotic change and to study global sea-level fluctuations, physical andchemical paleocean dynamics, biotic evolution, hydrology and diagenesis.

To investigate the origin, growth, compositional variation, and subsidence history ofthe Large Igneous Province (LIP) formed by the Kerguelen Plateau and Broken Ridge.

JOIDES Resolution Schedule for Legs 174B-183

LEG 174B: CORK/EngineeringU.S. Co-Chief: K. Becker, RSMASODP Staff Scientist: M. MaloneLDEO Logging Scientist: D. GoldbergLDEO Logging Scientist: Y.F. SunM. Fuller, U of HawaiiR. Harris, U of Miami

LEG 175: Benguela CurrentU.S. Co-Chief: W. Berger, SIOODP Staff Scientist: C. RichterD. Adams, SUNY PlattsburghD. Andreasen, UC Santa CruzL. Davis Anderson, UC Santa CruzV. Bruchert, Indiana UB. Christensen, U of South CarolinaG. Frost, UC Santa CruzT. Gorgas, U of HawaiiC. Lange, SIOP. Meyers, U of MichiganR. Murray, Boston UM. Perez, SIO

The short,brochure version

of the ODP’s GreatestHits abstract volume is

now available. This versioncontains only 17 of the morethan 120 abstracts received,and is specifically intended

for port calls and otherevents where a full

Greatest Hitsabstract volume

would not berequired.

Visit the JOI web site at www.joi-odp.org or requesta copy by e-mail from [email protected].

Work continues on the full version of ODP's GreatestHits. Many of the abstracts are already up on the JOIweb site (www.joi-odp.org) and more are being add-ed every week. A printed version of the full abstractvolume will be available by mid-November, in time forNSF’s National Science Board review of ODP renewal.


Table 1: Comparison of fluid-flow characteristicsin different tectonic regimes

The significance of fluid flow through oceanic crustcontributed by Miriam Kastner and Earl E. Davis

BOREHOLEREPORT

Miriam Kastner isProfessor, Geosciences

Research Division,Scripps Institution of

Oceanography. She hasbeen department chair

for the last four yearsand is currently vice-

chair. Miriam is also thegeology and geochem-

istry curricular groupsstudent advisor. She

has participated in twoDSDP and five ODP

legs to date.

luids are present in almost all Earth environments and play an important role in most crustal and mantle processes.Fluids are present in the pore spaces ofsediments and rocks beneath the seafloor;their depth of penetration and rate of flow arecontrolled by the porosity and permeability ofthe host formation and by gradients in fluidpressure. Most of the fluid is seawater whichhas percolated into the rock; in addition,hydrous minerals such as clays, serpentines,and amphiboles have structurally boundwater which is released by dehydrationreactions at elevated temperatures andpressures. The presence and migration ofthese fluids influence Earth’s heat budget,rock genesis and erosion, dissolution, cemen-tation, and deformation, mineralization,hydrocarbon migration, gas hydrate forma-tion, benthic biology, and magmatism. Tobetter understand the physical and chemicalevolution of the oceanic crust and global bio-geochemical cycles, it is essential to studyfluid-rock reactions and fluid-flow pathwaysin a variety of oceanic settings. Ocean drillingis critical for these studies.

State of knowledge

Mid-ocean ridges. At mid-ocean ridges,hydrothermally heated and chemically alteredseawater circulates rapidly through theoceanic crust at temperatures up to 350° -400° C, to a depth of a few kilometers. Thehot water reacts with and leaches basemetals from the sediments and rocks, formingpolymetallic sulfide deposits (mostly of Cu,

Zn, and Fe) at the seafloor and in the upperoceanic crust. This vigorous convective flowsystem hydrates the basaltic basement, altersseawater composition (stripping it of its Mgand SO4, enriching it in major and minorcomponents, i.e., Ca, Li, Si, Mn), and sustainsprolific benthic communities. The wholeocean volume circulates through the ridge-crest hydrothermal systems once in a about10 million years [e.g.: Stein and Stein, 1994;Elderfield and Schultz, 1996].

Ridge flanks and ocean basins. At ridgeflanks that have been cooled and partially orcompletely covered by sediments, fluid flowthrough the upper oceanic crust is lessvigorous but pervasive. It is also mostlydriven by thermal buoyancy. Fluid advectioncontinues for tens of millions of years, and isresponsible for the low conductive heat flowobserved in large regions of the ocean [e.g.:Baker et al., 1991; Langseth et al., 1992; andreferences therein]. This less spectacular butimportant flow occupies about 60 percent ofthe ocean floor. As yet it has not received asmuch attention as the vigorous flow at theridge crest. It has been the focus of study atDSDP Sites 395 [Langseth, et al., 1992] and504 [Langseth et al., 1988] and during ODP Leg168 [Davis et al., 1997]. This type of fluid flowoccurs at lower temperatures and thereforehas a lesser effect on the composition ofseawater; but it profoundly affects the oce-anic crust heat budget, continues to hydrate itto an as yet unknown depth (to at leastseveral hundreds of meters) and extent, anddiagenetically alters the basal sedimentsections above it. The ocean volume maycirculate through the ridge flanks system in aslittle as one million years [Elderfield andSchultz, 1996]. In ocean basins, pore fluidsare mostly in diffusive communication withbottom seawater. Rates of advection arebelieved to be thermally and geochemicallyinsignificant, although more work is requiredin areas of ancient seafloor.

Passive margins. Recent evidence from ODPlegs and modeling studies suggest that largescale sea water circulation within carbonateplatforms and continental margins is prima-rily thermally driven. Depending upon thesediment permeability and anisotropy smallercirculation cells may develop nearer the

TECTONIC DRIVING FORCE OCEAN VOL. DEPTH OFENVIRONMENT FOR FLUID FLOW RECYC. TIME WATER PENET.

Mid-ocean ridges Buoyancy and forced ~10 my a few km

MOR flanks Buoyancy ~1 my a few hundred m?

Ocean basins Forced unknown tens to a fewhundreds of m

Passive margins Topography and buoyancy unknown a few hundred m?

Subduction zones Forced (and buoyancy) 300-500 my tens of km

Buoyancy flows: flow due to fluid buoyancy differences (because of heating orcomposition, both of which influence fluid density)

Forced flows: flow due to an imposed condition (includes topography withrecharge, compaction, diagenesis, and tectonics)

F

July 1997, Vol 10, No 2 15

VOLCANICARC

SERPENTINITEDIAPIRS

FLUID VENTING SUSTAININGBIOLOGICAL COMMUNITIES

ACCRETEDSEDIMENT MUD

DIAPIRS SEDIMENT

OCEANIC

CRUSTUNDERTHRUST

SEDIMENT

DÉCOLLEMENTZONE

O5

O4 O2

O1I1

I2

O3

Tomantle

Magma

generation

Mineral dehydration and

hydrocarbon generation

Tectonic

compaction

1 2 1 2 3 4 5 6

1

2

1

2

3

4

5

6O ?6

I = Input O = Output

= Diffuse fluid flow

= Focussed fluid flow along the

décollement and other high

permeability faults

O2

FLUID MASS BALANCE

I + I = O + O + O + O + O + O + R

I = Sediment with pore fluid

I = Hydrated oceanic crust

O = Tectonic compaction

O = Dehydration of hydrous minerals and hydrocarbon generation

O = Dehydration of oceanic crust

O = Serpentinization and diapirism

O = Magma generation

O = To mantle (?)

R = Residual fluid

sediment surface and water can actually beseen to discharge and recharge in placesthrough the platform sides. Such flow hasbeen documented during the drilling of theQueensland Plateau off Australia (ODP Leg130) and the Great Bahama Bank (ODP Leg166). The flow can be recognized by thepresence of isothermal and isochemical porewater profiles in the sediments. This fluidcirculation has significant implications uponthe processes which convert the sediment intolimestone and dolomite, and may influencethe fluxes of Ca, Mg, and C in the oceans.This circulation also provides a mechanismfor electron acceptors to oxidize organicmaterial, and where fluid flow is rapid itprovides nutrients that sustain benthiccommunities [e.g., Paull et al., 1992]. Esti-mates of topographically driven hydrologicflow from continents through passive marginssuggest that these fluxes may also be large[COSOD II, 1987].

Subduction zones. Fluids play a critical rolein virtually all geologic processes in subduc-tion zones. Tectonic forces cause migrationand expulsion of pore fluids by reducingporosity, increasing the sedimentary load andgenerating fluid by dehydration, transforma-tion, and dissolution of hydrous minerals.

These fluids give rise to high pore fluidpressures and may trigger hydro-fracturing.Fresh water from dehydration also dilutes thepore fluids, and thus increases the buoyancyof the deeper, warmer fluids. As indicated by10Be, these fluids are also involved in arcvolcanism [Tera et al., 1986]. The mode offlow varies from the trench to the arc volca-noes, as illustrated in Figure 1. Focused flowrates of 100 m/y in Cascadia [Carson et al.,1990] and 17m/y at Barbados [Martin et al.,1996] through mud volcanoes have beendocumented. Diffuse flow rates are muchlower, but may also be important. Localchemical anomalies, the composition of veinminerals [Labaume et al., 1997] and thermalmodeling suggest that focused flow is epi-sodic. The exiting fluids carry into the ocean amultitude of dissolved components, includingenvironmentally important ones (i.e., CO2,CH4) that may significantly influence seawaterchemistry. Mass balancing will require deepdrilling. These fluids sustain benthic biologi-cal communities [e.g.: Kulm et al., 1986;Carson et al., 1990; Le Pichon et al., 1990;Kastner et al., 1991]. Preliminary estimatessuggest that the whole ocean volume circu-lates through subduction zones in less than afew hundred (300-500) million years.

Fig. 1: Illustration of fluidsrecycling in subduction zones.

Earl Davis is a geophysi-cist at the PacificGeoscience Centre,Geological Survey ofCanada. He has beenstudying crustal fluid flowfor many years by usingseafloor heat-flowmeasurements to inferrates of flow, and bymeasuring formationpressures in andpressure gradientsbetween ODP boreholes.Earl was co-chief scientiston Leg 168, which wasfocused on the physicsand chemistry of large-scale fluid flow on mid-ocean ridge flanks.Together with severalother anxious colleagues,he is nervously waiting torecover a year’s worth ofhydrologic data from sixsites drilled and instru-mented during Legs 168and 169.


CORKobservatory

ODPreentrycone

Sensorstring

Open-holeor

perforatedcasing

Casing

Seawater composition is thusstrongly imprinted by its continu-ous circulation through the variousoceanic crustal hydrologic regimesand interaction with the sedimentsand rocks along the pathways.Characterizing and quantifying thevarious fluid-rock reactions andhydrologic regimes is thereforemost important. For this reason, anew focus is being given to newand innovative field and laboratoryexperiments for short and long-range monitoring of each of thesefluid flow regimes in both bore-holes and on the seafloor. Asummary of these fluid flowregimes is provided in Table 1.

Short and long-term observations

Most of the information on fluidflow and composition has beenderived from seafloor geophysicalimaging, heat flow measurements,and chemical profiling of deepcores obtained by the DSDP andthe ODP. Much information hasbeen obtained from in situ observa-tions and downhole experimentsmade in ODP boreholes, withemphasis on logging, temperatureand pressure measurements,

hydrologic experiments, and fluid chemistry.These measurements and experiments arenormally conducted immediately after drill-ing, thus in a somewhat disturbed drillingenvironment.

With the advent of the ODP borehole seal, orCORK (Circulation Obviation Retrofit Kit;Figure 2), it became possible to instrumentholes for long-term monitoring of a multitudeof fluid physical, thermal, and chemicalproperties after dissipation of the drilling-induced disturbances. Recent specializedinstruments developed and deployed inCORKs are temperature and pressure sensors,tilt sensors for monitoring tectonic deforma-tion [Davis and Becker, 1993/94], and osmoti-cally pumped fluid samplers for continuousmonitoring of fluid composition [Jannasch andKastner, 1995; Jannasch et al., 1996] (Figure 3).CORKs have been installed and instrumentedin the submarine hydrothermal flow regimesof the Juan de Fuca Ridge, and Ridge flank, onthe western flank of the Mid-Atlantic Ridge(Hole 395A), and in two accretionary prisms,at Barbados and Cascadia. Osmotically

pumped fluid samplers have been installed inone of the Barbados CORKs (Site 949) and atthe Juan de Fuca Ridge; as yet they have notbeen recovered. Hydrologic experiments wereconducted at several of the CORKs, some ofwhich have been visited more than once[Davis and Becker, 1993/94; Davis et al., 1995;Screaton et al., 1997; and references therein].

... continued on page 24

Fig. 2: Illustration of an ODP bore-hole seal or CORK.

ReferencesBaker, P.A., P.M. Stout, M. Kastner, and H. Elderfield, Large-scale lateral

advection of seawater through oceanic crust in the central equatorialPacific, Earth Planet. Sci. Lett., 105, 522-533, 1991.

COSOD II, Report of the second conference on Scientific Ocean Drilling,European Science Foundation, Strasbourg, 67-86, 1987.

Carson, B., E. Suess, J.C. Strasser, Fluid flow and mass fluxdeterminations at vent sites on the Cascadia margin accretionaryprism, J. Geophys. Res., 95, 8891-8897, 1990.

Davis, E. and K. Becker, Studying crustal fluid flow with ODP boreholeobservations. Oceanus, 36, 82-86, 1993/94.

Davis, E.E., K. Becker, K. Wang, and B. Carson, Long-term observationsof pressure and temperature in Hole 892B, Cascadia accretionaryprism, Proc. ODP Sci. Results, 146, 299-311, 1995.

Davis, E.E., A.T. Fisher, J. Firth, and Sci. Party, Drilling program tracesfluid circulation through Juan De Fuca Ridge crust, EOS, 78, 187-189,1997.

Elderfield, H., and A. Schultz, Mid-ocean ridge hydrothermal fluxes andthe chemical composition of the ocean, Ann. Rev. Earth Planet. Sci., 24,191-224, 1996.

Jannasch, H. W. and M. Kastner, Long term continuous monitoring offluid composition with an osmotically pumped fluid sampler,International Lithosphere Program Workshop, Dynamics of LithosphereConvergence, 5, Japan, 1995.

Jannasch, H.W., C.G.Wheat, and M. Kastner, Sample resolution in long-term osmotically pumped continuous fluid sampler, EOS, 77, 725,1996.

Kastner, M., H. Elderfield, and J.B. Martin, Fluids in convergent margins:what do we know about their composition, origin, role in diagenesisand importance for oceanic chemical fluxes, Philos. Trans. R. Soc.London, A., 335, 243-259, 1991.

Kulm, L.D. et. al., Oregon subduction zone: venting, fauna, andcarbonates, Science, 231, 561-566, 1986.

Labaume, P., M. Kastner, A. Trave, and P. Henry, Carbonates veins fromthe decollement zone at the toe of the Northern Barbadosaccretionary prism: microstructure, mineralogy, geochemistry, andrelations with prism structures and fluid regime, Proc. ODP, Sci.Results, 156, in press, 1997.

Langseth, M.G., M.J. Mottl, M.A. Hobart, A.T. Fisher, The distribution ofgeothermal and geochemical gradients near Site 501/504: implicationfor hydrothermal circulation in the oceanic crust,Proc. ODP Init. Rep.,111, 23-32, 1988.

Langseth, M.G., K. Becker, R.P. Von Herzen, and P. Schulthesis, Heatand fluid flux through sediment on the western flank of the mid-Atlantic Ridge: a hydrogeological study of North Pond, Geophys. Res.Lett., 19, 517-520, 1992.

LePichon, X., P. Henry, and S. Lallement, Water flow in the Barbadosaccretionary complex, J. Geophys. Res., 95, 8945-8967, 1990.

Martin, J. B., M. Kastner, P. Henry, X. Le Pichon, and S. Lallement,Chemical and isotopic evidence for sources offluids in a mud volcanofield seaward of the Barbados accretionary wedge, J. Geophys. Res.,101, 20,325-20,345, 1996.

Paull, C.K., J.P. Chanton, A.C. Neumann, J.A. Coston, and C.S. Martens,Indicators of methane-derived carbonates and chemosyntheticorganic carbon deposits: examples from Florida escarpments, Palaios,7, 361-375, 1992.

Screaton, E., A. Fisher, B. Carson, and K. Becker, Barbados ridgehydrogeologic tests: implications for fluid migration along an activedécollement, Geology, 25, 239-242, 1997.

Stein, C.A. and S. Stein, Constraints on hydrothermal hear flux throughthe oceanic lithosphere from global heat flow, J. Geophys. Res., 99,3081-3095, 1994.

Tera, F., L. Brown, J. Morris, I.S. Sacks, J. Klein, et al., Sedimentincorporation in island-arc magmas: inferences from 10Be, Geochim.Cosmochim. Acta, 50, 535-550, 1986.

July 1997, Vol 10, No 2 17

Planning for a new ocean drilling programContributed by J. Paul Dauphin, Associate Program Director, NSF/ODP

NSF Report

lanning for scientific ocean drilling post- 2003 has increased in intensity in the past few months as the formational meet-ing of the International Working Group (IWG)of the Integrated Ocean Drilling Program(IODP) took place in Brest, France followingthe recent Executive Committee and ODPCouncil meetings. IODP is based on a two-ship program, one of which is a riser drillingvessel and the other is a JOIDES Resolution-type vessel. The IWG is comprised of organi-zations which are potential participants in theIODP. The co-chairs of this working group areMike Purdy, Director of the Ocean SciencesDivision at NSF, and Tsuyoshi Maruyama,Science and Technology Agency, Japan. Thiswas a formative meeting; more substantivediscussions are expected when the IWGmeets in September in Washington, DC.

As part of the planning process for scientificocean drilling post-2003, the NSF’s OceanSciences Division asked USSAC to assess U.S.interest in scientific ocean drilling beyond2003, the scientific objectives the scientificocean drilling community wishes to pursue,and what facilities and funds are required tomeet those objectives. The report, COMPOST-II, has been delivered to NSF and a copy canbe viewed and downloaded from the JOI website at http://www.joi-odp.org. The report isconsistent with the concept of a two drillingvessel program as identified by the IODP.Everyone interested in the future of scientificocean drilling should read this document andforward their comments to USSAC.

At the June meeting of the ODP Council, all ofthe existing ODP partners expressed veryoptimistic intentions to renew their participa-tion for the period 1998 to 2003. A panel wasconvened by NSF in late June to review theODP as a step in the process which seeksfunding approval from the National ScienceBoard (NSB) for the period 1998 to 2002.

This is an opportune time to remind everyonethat the NSF/ODP office is continuing itseffort to encourage the development ofmature proposals for regional geological andgeophysical studies well in advance of drillingfrom U.S. scientists and institutions. Inkeeping with the thematic emphasis of theODP, the NSF will accept proposals for work

in any ocean. However, as the internationalplanning effort focuses drilling plans on aparticular region, proposals for work in thatregion will receive special attention.

Proposals are evaluated according to normalNSF merit review criteria, as well as theirrelation to ODP planning. Thus these propos-als should contain a separate section (two orthree pages) that specifically addresses thepotential of the proposed research to enhancethe effectiveness of and scientific return toODP. This section should discuss both long-term ODP goals (as outlined in the ODP LongRange Plan, or LRP, available from JOI) aswell as the specific scientific problems to beaddressed. The target dates for submittingproposals to ODP are February 15 and August15, the same dates as Ocean Sciences Re-search Programs.

Please note that the NSB has approved newcriteria for review of NSF proposals, effectiveOctober 1,1997. To view the new criteria goto the NSF on-line Document System at http://www.nsf.gov/cgi-bin/pubsys/browser/odbrowse.pl or order a copy from the NSFForms and Publications Unit.

P

Recently funded ODP/NSF fieldand other programs

A gravity survey to characterize sulfide deposits in the Middle Valley region off theNW coast of the U.S. and test a new towed gravity system. Zumberge (SIO)

A detailed seismic survey of the New Jersey margin to tie results of on-shore and off-shore drilling focused on understanding the history and amplitude of Tertiary sealevel change. On-shore drilling has been supported by NSF’s divisions of EarthSciences and the Ocean Drilling Program, off-shore seismics by ONR and ODP, andoff-shore drilling by ODP. Mountain (LDEO) and Miller (Rutgers).

Site survey efforts of the South West Indian Ridge area of ODP hole 735B relatingprevious drilling results to surrounding seafloor geology and provide additional datafor future drilling. Dick (WHOI) and Natland (RSMAS). Joint funding with the UK.

Seismometer deployment in early 1998 at the Ocean Seismic Network site south ofHawaii. Orcutt (SIO), Stephen (WHOI).

Carbon flux studies using aerobic and anaerobic chambers connected to the existingborehole seal at Site 892 on the Oregon margin. Carson (Lehigh) and Kastner (SIO).

NSF funding support for an office at the University of Hawaii to provide theorganization and planning necessary to achieve the coordinated multidisciplinaryresearch goals of the MARGIN initiative. Taylor (SOEST) Jointly funded by ODP andMG&G, Ocean Sciences Division, and Continental Dynamics, Earth Sciences Division.


Contributed by Casey Moore and Greg Moore

SEIZE: The seismogenic zone experimentWorkshopReport

ost of the world’s great earthquakes and tsunamis are initiated in the zone of underthrusting, or seis-mogenic zone, of subduction zones. Fiftyearth scientists (including 18 from outside theU.S.) gathered in Kona, Hawaii during theweek of June 2 to discuss approaches tounderstanding the seismogenic zone. Theworkshop, sponsored by JOI/USSAC and NSF/MGG, started with an informal evening postersession followed by a day of talks focused onimportant issues relating to future Seis-mogenic Zone Experiments. The remainingday and a half consisted of spirited discus-sions of the key elements of potential SEIZEfield study areas.

The workshop built on a 1995 conference onthe same topic sponsored by the InternationalLithosphere Project, and outlined the goals ofa seismogenic zone experiment: SEIZE hopesto understand the relationship betweenearthquakes, deformation, and fluid flow inthis environment. SEIZE will address thefollowing questions: 1) What is the nature ofasperities? 2) What are the temporal relation-ships between stress, strain, and fluid com-position throughout the earthquake cycle? 3)What controls the up-and downdip limits ofthe seismogenic zone? 4) What is the natureof tsunamigenic earthquake zone? 5) What isthe role of large thrust earthquakes in mate-

rial mass flux (e.g., accretion vs. sedimentsubduction vs. tectonic erosion) in subductionzones?

SEIZE will proceed by focused investigationscombining earthquake seismology, seismicreflection imaging, and geodetic studies inand around a limited number of seismogeniczones. Sampling the incoming materialcombined with laboratory experiments andmodeling will be used to predict the nature ofthe fault rock in the seismogenic zone.Waveform models of the seismic images willbe used to predict physical properties of theseismogenic zone. Deep riser drilling will beused to test these models, lead to a betterunderstanding of our questions about theseismogenic zone, and calibrate techniquesfor monitoring changes in fault zones duringthe earthquake cycle.

Seismogenic zones selected for focused studymust have historic earthquake activity, beimagable by seismic reflection, be geographi-cally accessible, and ultimately be penetrableby drilling. At the SEIZE workshop, applica-tion of these criteria to candidate localitiestargeted off the Japanese Islands (NankaiTrough and Japan Trench) and CentralAmerican (Costa Rica and Nicaragua) forSEIZE programs. The extraordinaryinfrastructural investments, the large societal

MThe full SEIZE reportis available at http://

www.soest.hawaii.edu/moore/seize.

Casey Moore isProfessor of Earth

Sciences at theUniversity of California,

Santa Cruz.

Gregory Moore isProfessor in the

Department of Geologyand Geophyisics,

University of Hawaii.

0 10

km

Determine incomingmaterial flux

Measure surface deformation

Image seismogenic zone using earthquakes and artificial sources (seismic reflection)

Drill to seaward limitof seismogenic zone

Predict nature ofdeeply recycled materials

Predict nature of materials in

seismogenic zone

Seismogenic zone

5

10

15

0 km

20

25

30

July 1997, Vol 10, No 2 19

relevance, the seismic imaging possibilities,and the drilling potential in the Japan arearequire focus there. Central America, espe-cially Costa Rica, offers exceptional opportu-nities for seismic and geodetic monitoring,can be imaged and drilled, and contrastsgeophysically with the Nankai Trough localityin Japan. Japan Trench and Nicaragua havegenerated tsunamigenic earthquakes war-ranting investigation. Investigations in theNankai Trough in Japan will have direct

application to understanding the societallyrelevant, currently quiescent but paleoseis-mically active Cascadia seismogenic zone ofthe Pacific Northwest.

SEIZE is one component of the new U.S.MARGINS initiative at NSF and will be in-cluded in future MARGINS funding. The nextdiscussion of SEIZE took place at the CON-CORD meeting in Japan.

Jamie Austin, University of Texas, AustinGlobal sea-level fluctuations: ODP’s inauguralexpedition to the New Jersey continental shelf

• College of William and Mary, Williamsburg, Virginia• Five College Coastal and Marine Sciences Program,

Northampton, Massachusetts• Auburn University, Auburn, Alabama• Vanderbilt University, Nashville, Tennesee• Trinity University, San Antonio, Texas• University of Houston, Houston, Texas

Margaret Delaney, University of California, Santa CruzA focus on phosphorus

• Ohio University, Athens, Ohio• Appalachian State University, Boone, North Carolina• University of Vermont, Burlington, Vermont• Harvard University, Cambridge, Massachusetts• Humboldt State University, Arcata, California

Gregor Eberli, University of MiamiSea-level changes: The pulses of sedimentationon carbonate platform margins

• University of Maine, Orono, Maine• University of Kentucky, Lexington, Kentucky• University of Arkansas, Fayetteville, Arkansas• Williams College, Williamstown, Massachusetts• University of Georgia, Athens, Georgia

1997-98 JOI/USSAC Distinguished Lecturer Series underwayJOI is pleased to announce the institutions the 1997-98 distinguished lecturers will visit duringthe 1997-98 academic year. It was difficult to select the host institutions from the large num-ber of excellent applications received by JOI.

Deborah Kelley, University of WashingtonVolatile-fluid evolution in submarinemagma-hydrothermal systems

• South Dakota School of Mines and Technology,Rapid City, South Dakota

• Montana Tech. of the University of Montana,Butte, Montana

• Bowling Green State University, Bowling Green, Ohio• Bloomsburg University of Pennsylvania,

Bloomsburg, Pennsylvania• Scripps Institution of Oceanography,

La Jolla, California

Larry Peterson, University of MiamiClimate change in the tropical Atlantic: Clues topatterns and processes from the Cariaco Basin

• University of Pittsburgh, Pittsburgh, Pennsylvania• Lafayette College, Easton, Pennsylvania• Michigan State University, East Lansing, Michigan• University of Wisconsin, Madison, Wisconsin• University of Florida, Gainesville, Florida

Haraldur Sigurdsson, University of Rhode IslandGlobal episodes of explosive volcanism:Evidence from ODP Leg 165

• Arizona State University, Tempe, Arizona• Brigham Young University, Salt Lake City, Utah• Colorado State University, Fort Collins, Colorado• Northern Illinois University, DeKalb, Illinois

JOI/USSACDLS


T

A letter to the ODP scientific communityODPPublications

Dear Colleague,

he recent decision on ODP publications by EXCOM has caused widespread discus- sion within the ODP community. In this replyI would like to describe, in more detail, thebackground and rationale behind the recentEXCOM decisions regarding publications(copies of which are attached for your informa-tion), and the steps which are being taken toaddress some of the concerns many of you haveexpressed regarding the possible phasing out ofpublication of a printed IR [“Initial Reports”].

The changes in ODP publication policy havebeen motivated in part by a desire to cut, or atleast contain, costs. ODP has been flat fundedfor the past five years, which means, in realdollars, the ODP budget is now about 14% lessthan it was in 1994. Almost all of the interna-

tional partners in ODPhave stated that PhaseIII renewal is contin-gent upon a fixedmembership fee, i.e. noinflation correction.This means that anyincrease in funding forODP over the period1999-2003 will bedependent on theaddition of newmembers to theProgram (an uncertainprospect at best). Ifcurrent trends con-tinue, by the year 2000ODP could be operat-ing on a budget that is20% less in inflation-adjusted dollars thanin 1994. And this is inthe face of costs insome areas, e.g.,drilling supplies andservices, that areincreasing much fasterthan the CPI. This hasput enormous financialpressure on theProgram. ODP’s twomain subcontractors,TAMU and LDEO, havealready been subjectedto stringent cost-cutting (with staff

reductions and reorganizations), and there isgeneral agreement that any further cost savingswill be small, unless existing program servicesare cut back or eliminated. At the same time, itis clear that continued funding of ODP isdependent on the program pursuing the newinitiatives and technical innovation outlined inthe ODP Long Range Plan. Any perception thatODP is conducting “business as usual” mayvery well jeopardize the contributions of somepartners, with a resulting domino-effect thatcould terminate the entire Program. The combi-nation of flat budgets, and the need for newProgram initiatives, means that additional costsavings have to be realized to offset the effectsof inflation and to fund the new scientific andtechnological initiatives the community hasidentified in the ODP Long Range Plan. The ODPpublications budget which runs close to $2M/yrhas been one of the areas that has been care-fully scrutinized in this regard.

Another important motivation for changes intraditional ODP publications, however, stemsfrom a desire to take advantage of the enor-mous potential of electronic publication and theInternet to distribute data and information innew ways to ODP scientists, and to a muchbroader community. Indeed, at least twomembers have made major changes in ODP’spublication policy a prerequisite for Phase IIIrenewal. Electronic versions of the Proceedingscan potentially allow direct links between theIR, the SR and the ODP JANUS database, as wellas to ODP-related publications in the outsideliterature. This will allow new ways of retrievingand using ODP data that were not previouslypossible with traditional paper volumes.Another benefit of putting the IR and SR ontoCD-ROM and the WWW will be much wideraccess by a broader scientific community,including industry. Only about 1200 of theprinted volumes are currently circulated world-wide. Many universities and research institu-tions, in both developed and less developedcountries, are not receiving the printed IR andSR, but have access to the WWW or CD-ROM-equipped computers. The marginal cost of aCD-ROM version of an IR, or SR (with explana-tory notes), is likely to be less than $5, vs morethan $60 for the current printed volume. Wecould envisage circulating perhaps 5,000 copiesof the CD-ROM version potentially reaching amuch wider audience. Indeed, few people havedisputed the potential advantages of electronicpublication; the question has really been

EXCOM MOTION 97-2-6

The EXCOM recognizes that the Publications ofODP are an important mechanism by which theprincipal legacy of the program, its scientificfindings, are conveyed to the scientificcommunity, and by which an additional legacy,the scientific samples, are described to thecommunity. We appreciate the concern of theSCICOM for the importance of this communica-tion mechanism. We also appreciate the workthat the Publications Committee has done topoll our community about its capability and itscontinuing commitment to advise us about theaccess and format of our publications.

The severe fiscal constraints imposed bymember contributions anticipated for Phase IIIof ODP require that we exercise great care inbalancing priorities for the ODP activities. Firstand foremost among those are to fostertechnological innovation and make progresstoward implementing our science plan. Budgetprojections from our operators indicate that itwould be impossible to do so if we accept theextra costs associated with the recommenda-tion of the JOI Publications Steering Committeeto continue traditional paper publication of theInitial Reports (IR) for several years.

As a result, the EXCOM reconfirms its 1996schedule for introducing electronic and CD-ROM publication of the IR and SR volumes andphasing out paper publication. We agree tocap the volume publication budget at the levelsindicated in the JOI model for FY 99 andbeyond.

We have asked JOI to explore outsourcingpublications as an additional option and havealso asked that they check obligations forpublications in the MOUs and seek relaxation ofthese obligations if necessary.

July 1997, Vol 10, No 2 21

“when,” or even “if,” the printed volumesshould be phased out.

Over the past 3 years, the future of ODP publi-cations has been discussed by various commit-tees within the JOIDES advisory structure and aplan has been in place for more than a year tomove ODP toward electronic publication of itsIR and SR volumes. In December, 1994, a PCOMPublications Steering Committee (PSC) wasestablished to investigate ways of cutting ODPpublications costs by up to 30%. In April, 1995PCOM reviewed and endorsed the recommenda-tions of the PSC which included cutting the IRbook to 100 pages of text (with the rest on CD-ROM), reducing the size of the printed corephotos by 50%, and reducing the number ofpages in the SR volumes by 40%. These recom-mendations were, however, never fully imple-mented. In June, 1996, EXCOM was presentedwith, and approved, a new ODP publicationsstrategy developed by JOI and the PSC. Thisplan called for the phasing out of both theprinted IR and SR volumes over several yearsand their publication on CD-ROM and theWWW, as well as allowing publication of post-cruise results in the outside literature 12 monthspost-cruise. In August, 1996, PCOM endorsedthis plan with the condition that full electronicpublication proceed only when the communitywas ready. In December, 1996, JOI established anew Publications Steering Committee (PUBCOM)to oversee the transition to electronic publica-tion. This committee met in April, 1997 andrecommended that the transition to an elec-tronic/WWW SR proceed as planned but thatthe IR continue to be produced in print and CDformats for at least another 3-5 years . It wasthis recommendation, endorsed by SCICOM inApril, that was presented to EXCOM in June.

Continuing to produce printed IR volumes intheir present form, as recommended byPUBCOM, would cost the program an additional$1.8M over the period FY 98-02. This may seemlike a small fraction of the annual $44.4 millionODP budget, but ODP is a program with veryhigh fixed costs. Excluding the SEDCO contractfor the drillship, ODP (including TAMU, LDEOand JOI/JOIDES) operate on an annual budget of~$21 million. Within this figure ODP has a verysmall “discretionary” budget. In FY 98 this so-called Special Operating Expense (SOE), or X-based budget, will be about $3.7M. It is thisbudget that supports new engineering develop-ment (e.g. development of DCS or active heave

compensation for barerock drilling), CORKSand hard rockguidebases, specializedlogging tools (e.g. LWD),iceboats or alternativedrilling platforms - i.e.all the costs beyond thatof a “standard” drilling leg. Budget projectionsfor FY 99 and beyond indicate this SOE or X-based budget will drop to about $2M/yr.Measured against this, the $400K/yr for pub-lishing the IR books is a significant number. Itcould be the difference between being able tohave an ice support vessel for an Antarctic leg,or LWD and CORKS for drilling an accretionarywedge, or contracting for an alternative drillingplatform for the New Jersey margin. It was withthis perspective in mind that EXCOM recom-mended to JOI that the program simply cannotafford to continue to produce, print and distrib-ute 1200 copies of the traditional IR volumes intheir present form for another 3-5 years.

This was not an easy decision. EXCOM wasfully aware of the importance that a largesegment of the ODP community attach to theprinted IR volume. Your messages over the pastfew weeks have made it very clear that even inthe face of these severe fiscal constraints asignificant segment of the community would stilllike to have the option of having a printed IR. Inresponse to these concerns JOI is currentlyinvestigating, within the budgetary constraintsof EXCOM motion 97-2-6, what options mayexist for continuing to provide access (poten-tially at some cost to users) of some form of aprinted version of the IR beyond October, 1998.JOI will report on these options at the earliestpracticable date.

This is the first of many difficult choices ODPwill have to face as it grapples with the cumula-tive effect of a budget which has been decliningin inflation-adjusted terms for 5 years. If youshare EXCOM’s concern about the long-termimpact of this “flat-funding” policy on ODP, andthe Program’s ability to implement its LongRange Plan, I encourage you to communicateyour concerns to your national funding agency.

Sincerely,

Bob Detrick, EXCOM Chairon behalf of the entireExecutive Committee

EXCOM MOTION 97-2-7

EXCOM asks JOI to provide advice on outsourcingall or part of ODP Publications. This advice shouldinclude electronic publications options and con-sider legal and financial issues. JOI should reporttheir findings at the January 1998 EXCOM Meeting.


How to make tough decisions in tough timesA letterfrom the

Chair

Dr. Roger Larson isProfessor of Marine

Geophysics, GraduateSchool of Ocean-

ography, University ofRhode Island.

A s I write my final editorial as USSAC Chairman, ODP stands at the brink of a potential financial crisis, broughtabout by the likely renewal of the programfrom 1998 to 2003, BUT with no increases infunding. As we have had no funding increasessince 1994, this potentially will result in a fulldecade of level funding, in contrast to theever-increasing costs of basic services for theprogram, not to mention the needs for engi-neering development and other special-costitems. In the face of that likely reality, there isno escaping the fact that things will have tobe cut, possibly even things that many of usconsider to be “basic services.” So the ques-tions really are; what do we cut, when, andhow do we make those decisions? The currentexample is the controversy over EXCOM’srecent decision to soon eliminate the InitialReports volume in hard-copy form. That issueis described elsewhere in this volume andcurrently is being addressed in other forums,so I do not want to add more fuel to thatparticular fire here. I would rather take alonger view of the problem; namely, how ingeneral should we address these sorts ofproblems in the future, hopefully to avoid thekind of controversy now raging over thepublications issue.

At the risk of sounding like one of your highschool sports coaches, we are going to haveto start playing more like a team. CaseyStengel once said, “To win the pennant, we’regonna to have to start thinking that we aren’tas good as we think we are.” That may soundlike an oblique way of putting it, but what Imean in this instance is that we are going tohave to put our individual egos aside, stopfighting amongst ourselves, and start fightingfor the common goal of preserving the mostvaluable and productive program earthsciences has ever seen. This does not mean tostop examining and arguing the issues thatconfront us. What it does mean, in myopinion, is that when an important decisionmust be made on which there apparently isno overall agreement, the group who must

make that decision should also ENGAGEother levels within JOIDES in that decision-making process. “Engage” sounds prettynebulous and it is, because I do not want toprescribe how that is done. It may be simplyby more informal discussions betweenindividuals at various levels within JOIDES, orwe may need more formal mechanisms. TheU.S. Congress has conference committees towork out differences in bills between theHouse and Senate. We have a Budget Com-mittee made up of joint membership ofSCICOM and EXCOM that could be used inthe future to deal with such matters at thatlevel. I don’t really care how this happens.My point is that we are rapidly reaching afinancial situation where we can no longerafford the luxury of simple serial-decisionmaking that goes monotonically up theJOIDES panel and committee structure,because the potential then exists for the sortof current blow up that we now have on ourhands. This is obviously going to be evenmore trouble and effort than decision makingis now within JOIDES, but we just have to doit, because we cannot afford to tear theprogram apart internally. I think that we CANdo this because this is a top-quality programrun by top-quality people. But now is thetime for us all to realize the effort that will berequired in the next few years to preservescientific ocean drilling well into the 21stCentury.

Having said that, I’d like to close by thankingeveryone for their support over the last twoyears while I have chaired USSAC. I especiallythank Ellen Kappel, Andrea Johnson, and JohnFarrell of the JOI Office, who have providedoutstanding support, and who are some ofthe program’s most valuable assets. I ampleased to have had the chance to serve.

Roger L. LarsonChairman, USSAC

USSAC Chair

July 1997, Vol 10, No 2 23

JOI/USSAC

* USSAC ExecutiveCommittee

Membership termis three years

Fall 1997

MEMBERSHIPROTATION

ROTATING ON:Steve Carey, URIRick Murray, Boston UDavid Naar, USFLisa Tauxe, Scripps

ROTATING OFF:John BarronRoger Larson**Jim OggBernd Simoneit

** Mike Arthur will takeover the USSACChairmanship fromRoger Larson on

October 1, 1997.

Dr. Michael Arthur*Department of GeosciencesPennsylvania State University503 Deike BuildingUniversity Park, PA 16802tele: (814) 863-6054fax: (814) [email protected]

Dr. James A. Austin, Jr.Institute for GeophysicsUniversity of Texas at Austin8701 North Mopac ExpresswayAustin, TX 78759-8397tele: (512) 471-0450fax: (512) [email protected]

Dr. John BarronU.S. Geological Survey, MS910345 Middlefield RoadMenlo Park, CA 94025tele: (415) 329-4971fax: (415) [email protected]

Dr. Rodey BatizaDept. of Geology & GeophysicsUniversity of Hawaii2525 Correa RoadHonolulu, HI 96822tele: (808) 956-5036fax: (808) [email protected]

Dr. William CurryDept. of Geology & GeophysicsWoods Hole Oceanographic Inst.Woods Hole, MA 02543tele: (508) 457-2000 x2591fax: (508) [email protected]

Dr. Margaret DelaneyOcean Sciences DepartmentUniversity of California, Santa Cruz1156 High StreetSanta Cruz, CA 95064-1077tele: (408) 459-4736fax: (408) [email protected]

Dr. Robert DunbarDept. of Geology & GeophysicsRice UniversityPO Box 1892Houston, TX 77251tele: (713) 527-4883fax: (713) [email protected]

Ms. Mary FeeleyExxon Exploration Company233 Benmar GP8/Room 791Houston, TX 77060-2598tele: (281) 423-5334fax: (281) [email protected]

Dr. Tim HerbertDept. of Geological SciencesBrown UniversityProvidence, RI 02912-1846tele: (401) 863-1207fax: (401) [email protected]

Dr. Roger Larson, Chair*Grad. School of OceanographyUniversity of Rhode IslandNarragansett, RI 02882tele: (401) 874-6165fax: (401) [email protected]

Dr. Marvin LilleyBox 357940School of OceanographyUniversity of WashingtonSeattle, WA 98195tele: (206) 543-0859fax: (206) [email protected]

Dr. Carolyn MutterInternational Research Institute for Climate PredictionLamont-Doherty Earth ObservatoryPalisades, NY 10964-8000tele: (914) 365-8628fax: (914) [email protected]

Dr. James OggDept. of Earth & Atmos. SciencesPurdue UniversityWest Lafayette, IN 47907tele: (317) 494-8681fax: (317) [email protected]

Dr. Terry Plank*Department of GeologyUniversity of Kansas120 Lindley HallLaurence, KS 66045tele: (913) 864-2725fax: (913) [email protected]

Dr. Bernd SimoneitCol. of Oceanic and Atmos. Sci.Oregon State UniversityOceanography Building 104Corvallis, OR 97331-5503tele: (541) 737-2155fax: (541) [email protected]

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The JOI/USSAC Newsletter is issued three times a year by Joint Ocean-ographic Institutions, Inc. (JOI) and is available free of charge. JOI managesthe international Ocean Drilling Program (ODP) and the U.S. ScienceSupport Program (USSSP) which supports U.S. participation in ODP.Funding for JOI/USSSP is provided through a cooperative agreement withthe National Science Foundation (NSF).

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Dr. J. Paul DauphinAssociate Program DirectorOcean Drilling ProgramNational Science Foundation4201 Wilson Boulevard, Rm. 725Arlington, VA 22230tele: (703) 306-1581fax: (703) [email protected]

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Fig. 3: Dr. Kastnerattaching the osmo-fluid sampler to the

drill string at ODPHole 949, Barbados.

Fluid flow in oceanic crust, continued from page 16

At subduction zones, short-term field experi-ments at vent sites have been conducted andfluid flow measured. The few short-termmeasurements of focused fluid dischargerates along prominent faults such as thedécollement, but mostly through active vents,are greater by orders of magnitude than theestimated fluid input rates [e.g.: Carson et al.,

1990; Le Pichon et al., 1990; Kastner et al.,1991]. These differences imply that the flowis episodic; local pore fluid chemical anoma-lies, composition of vein minerals, tempera-ture monitoring, and heat flow modelingsupport this conclusion [e.g.: Labaume et al.,1997; Le Pichon et al., 1990; Davis et al., 1995].There may be a linkage between theepisodicity of flow and earthquake cycles.

To determine the fluxes and composition ofthe expelled fluids in each of the sub-environ-ments, fluid flow rates and composition ofboth modes of flow, focused and diffuse, mustbe determined and integrated over time. Newseafloor and borehole samplers that will beable to capture both modes of fluid flow insubduction zones and ridge flanks over longtimes are being designed and developed. Tomake optimal use of boreholes in the future,the capability to carry out monitoring andsampling at multiple levels is important.Monitoring hydrothermal fluid flow rates andcomposition at ridge crests is the mostchallenging future objective because of thevery high temperatures and corrosive natureof these fluids, having pH values of ~3.5 andvery high H2S concentrations.

We would like to thank Andy Fisher, Peter Swart,and Keir Becker for reviewing this article.

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