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GRADSCHOOLGRADSCHOOLCONFERENCECONFERENCE

20062006

BEN WYVISBEN WYVIS

School of GeoSciences GradSchool Conference

2006

Ben Wyvis Sponsored by:

Other contributors: Melrose Resources MIMAS MTEM Rider–French SINTEF SUERC

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Contents

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Contents

CONTENTS .................................................................................................... 1

WELCOME ..................................................................................................... 2

GENERAL CONFERENCE INFORMATION .................................................. 3

CONFERENCE DELEGATES ........................................................................ 5

CONFERENCE SCHEDULE .......................................................................... 6

TALKS SCHEDULE ....................................................................................... 7

DINNER MENUS ............................................................................................ 8

ABSTRACTS: SESSION 1 (GREAT GLEN) ................................................ 10

ABSTRACTS: SESSION 2 (LOCH NESS)................................................... 15

ABSTRACTS: SESSION 3 (THE DALRADIAN) .......................................... 20

ABSTRACTS: SESSION 4 (THE MOINE).................................................... 25

ABSTRACTS: SESSION 5 (BLACK ISLE) .................................................. 30

ABSTRACTS: SESSION 6 (EATHIE) .......................................................... 35

ABSTRACTS: SESSION 7 (BEN WYVIS).................................................... 39

Welcome

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Welcome

Graduate School Conference, 3rd - 5th February 2006 Welcome to the Ben Wyvis Hotel for the 15th annual GradSchool Conference. This event is an important expression of the Graduate School’s objectives, to enhance communication and interaction within the postgraduate community. We seek to encourage discussion across perceived discipline barriers, and between the School of GeoSciences’ three component Institutes (Earth Science, Geography, Atmospheric and Environmental Science). For many of us, this weekend represents a first opportunity for the oral presentation of our studies in a conference environment; the spirit of the occasion allows this to be undertaken in a supportive atmosphere such as may not be found at larger meetings. For others this conference is a chance to become better acquainted with the wide range of research topics under investigation among colleagues. Interaction between industry and academia is an important aspect of the GradSchool Conference. Again this year we are privileged to welcome delegates from geoscience related industry, some of whom will be presenting results from their own studies during the Conference weekend. 2006 sees a change in conference venue, as the GradSchool committee welcomes you to the charming highland village of Strathpeffer, near Inverness. The geology and scenery of the region has provided inspiration for this year’s conference theme, ‘Ben Wyvis.’ You can discover more about Ben Wyvis and its surroundings later in the abstract volume. We would like to remind all those attending that this conference has only been made possible by generous donations from industry. This is support for which we continue to be most grateful. We hope you have a stimulating and enjoyable Ben Wyvis conference Gradschool Committee (2005 - 2006)

Steven Sawyer Janette Tourney Emma Passmore Isabel Varela

Karin Viergevier Emma MacLoughlin Joana Gafeira Nigel Kelly

Sarah Appleby Peter Mackintosh

General conference information

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General conference information Check-in/Check-out Rooms will be available for check-in from 1330 on Friday. You are asked to check-out of your room between 0930 and 1000 on the Sunday morning. Luggage storage and recovery rooms will be available on Sunday morning. Attire The Conference Dinner and Ceilidh on Saturday night are Black Tie. Casual wear is appropriate for all other times. About the area The Strathpeffer area boasts a record of settlement dating back to the Pictish pre-Scottish peoples of Caledonia. The town itself was founded as a Victorian Spa on the fame and reputed healing powers of its mineral springs. The Ben Wyvis Hotel typifies Strathpeffer’s rich Victorian legacy and is named in honour of the hill that it looks upon. Ben Wyvis is one of the most northerly of Scotland’s Munros (hills over 3,000ft) and rises to dominate the surrounding landscape, be that the Black Isle or the firths of Cromarty and Moray that bound it to the north and south respectively Dinner Dinner is served at 1930 on Friday, though late arrivals will be catered for where informed in advance. Please endeavour to be on time for all meals in order to allow the smooth running of the conference. Keys There is only one key per room. Since most delegates are sharing rooms, please keep a note of who has the key to avoid being locked out. Keys can be left at reception Talks The conference is scheduled to commence at 1400 on the Friday and to finish at 1400 on the Sunday. It is important that speakers keep within their allotted 15 minutes slot (10-12 minute presentation followed by questions) in order for the conference to progress smoothly. Prizes There will be prizes of book tokens for the best talk in two categories –best 1st Year and best Student. Three mystery guests will judge the talks. Field Excursion There will be a mystery field excursion on Saturday afternoon, involving elements of the local geology. Anyone wishing to attend is asked to sign-up in the hotel lobby on

General conference information

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arrival on Friday, also indicating if they can drive a car if required. A drying off room will be available for boots and coats, which anyone attending the excursion is requested to use. More information at the hotel reception upon arrival. Online Information For more information about Edinburgh University’s GeoScience Graduate Schools, visit http://www.geos.ed.ac.uk/postgraduate/GradSchool/ From here you will find links to conference abstract volumes past and present. The Future The GradSchool Conference is, and traditionally has been, an integral part of the GeoSciences calendar. If you are interested in being part of this event in 2007, please contact Ciaran Beggan, Graduate School President Elect [email protected]. If you have any further questions please contact Steven Sawyer [email protected] or any other member of the GradSchool committee.

Conference Delegates

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Conference Delegates Guests and affiliation David Bailey Cairn Energy Sonja Maultzsch Total Nick Banbury Statoil Joan Megson Maersk Oil Andrew Butler Amerada Hess Gail Millin MIMAS Tom Bradwell BGS Oscar Miron Melrose Resources Dave Cook ExxonMobil Malcolm Rider Rider-French Rob Ellam SUERC Johan Robertsson Western Geco Caroline Gill Shell Barbel Traub Sintef Scott Hadden Wood Mackenzie Clare Wilkie Maersk Oil Guy Hall MTEM Staff and Postdocs Mikael Attal Barry Dawson Stephan Klemme Laetitia Pichevin Geoffrey Boulton Dusan Djurdjevic David Krasa Chris Place Mark Chapman Ruth Dwyer Christopher MacLellan Sue Rigby Colin Chillcott Mary Elliot Justin MacNeil Alastair Robertson Yvonne Cooper Simon Harley Ian Main Stuart Simmons Andrew Curtis Staurt Haszeldine Caroline Nichol Shane Voss Janet Cuthill Nigel Kelly Ian Parsons Mark Wilkinson Stephen Davison Postgraduate students Cristina Aparicio Rachel Gaulton Peter Mackintosh Janette Tourney Sarah Appleby Caroline Graham Wendy Matthews Adrian Tuitt Elsa Arellano-Torres David Halliday Gillian McCay Isabel Varela Ciaran Beggan Andy Hein Emma McLoughlin Antoine Vernon Clare Britton Tim Hill Ueli Meier Karin Viergever Jonathan Butler Dan Hobley Abdulwasey Mohammed Lifeng Wang Iain Cameron Martin Howard Vicki Parry Axel Wellpott Andrew Casely Tim Ivanic Emma Passmore Kevin Welsh Zana Conway Huw Jones David Price Bronwen Whitney Andrew Cross Kevin Jones Zhongping Qian Alexander Whittaker Nick Cutler Fred Kigereigu Conrad Rider Adam Wilson Payal Debroy Tim Kinnaird Steven Sawyer Clare Woulds Sigrid Dengel Natasha Lee Natalie Starkey Din Yusoff John Dowens Luciana Londe Hannah Suttill Jinghua Zhang Joana Gafeira Jiemin Lu Richard Taylor Bold denotes speaker

Conference Schedule

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Conference Schedule Friday 3rd February 0900 Bus departs from Grant Institute 1330 - 1430 Room Check-in 1400 - 1500 Lunch Buffet 1500 - 1515 Welcome from GradSchool Chair 1530 Session 1: GREAT GLEN (5 talks) 1645 Afternoon Tea 1700 Session 2: LOCH NESS (5 talks) 1815 Close Session 1830 Drinks in Lounge 1930 Dinner in the Restaurant 2200 Quiz (name location) Saturday 4th February 0830 - 0930 Breakfast 1000 Session 3: THE DALRADIAN (5 talks) 1115 Coffee 1130 Session 4: THE MOINE (5talks) 1245 Lunch Buffet 1330 Field Trip (weather permitting) 1615 Afternoon Tea 1630 Session 5: BLACK ISLE (5 talks) 1830 Champagne Reception 1930 Conference Dinner 2130 - 0000 Ceilidh Sunday 5th February 0830 - 1000 Breakfast 0930 - 1000 Room Check-out (luggage and recovery room available) 1000 Session 6: EATHIE (5 talks) 1115 Coffee 1130 Session 7: BEN WYVIS (5 talks) 1245 Conference closing session and prizes 1400 Coach departs

Talks Schedule 7

Talks S

chedule Title

Quantifying the evolution of the Orange River basin, South Africa: new erosion rate data from terrestrial cosmogenic nuclides. Multi-Component AVO Inversion A magnetostratigraphy for the raised beach deposits of southern Cyprus: Early Pleistocene – Recent uplift of the island of Cyprus. Research at 63°23’ North Weathering of minerals in granite in the tropics

Fluid and anisotropy effects in porous rocks from seismic time lapse data Characterisation of Neotropical Savanna Ecosystems by their Modern Pollen Rain Controls and timing of structural inversion in the NE Atlantic Margin Remote Sensing of Peatlands: Classification of Blanket Bog Microhabitats using Spectral Library, Lidar and Hyperspectral Data Prestack depth migration of primary and surface-related multiple reflections

An integrated study of the role of distributed deformation in the collision of continents (Kyrenia Range lineament, Northern Cyprus) MTEM: Shallow Marine Trial Good for glaciers, bad for people? Disentangling the twin effects of climate and human impact in Norse Iceland Acoustic emissions as an indicator of damage The Kerala Khondalite Belt: A Natural Laboratory for Crustal Melt

The UK Satellite Image Data Service hosted at MIMAS – Providing Remote Sensing Products and Learning Resources for UK Academia 3D physical modelling for fracture characterisation Plumes and Picrites – a hot topic! Ecosystem development on the historical lava fields of Mt. Hekla, Iceland Development of the Balkan Fold-and-Thrust Belt Retro-Thrust wedge: evidence from the Western Black Sea and Eastern Bulgaria

Predicting Secular Variation using Core Flow Models The Nelson Field – A huge challenge for a new graduate The Origin of the Silverpit Structure; The Truth is Out There… Measurement of advection and surface-atmosphere exchange in complex terrain. Investigating the State of Western Warm Pool of the Tropical Pacific during a perturbed thermohaline circulation.

Can Anisotropic Dispersion be used for Fluid Discrimination and Fracture Characterisation? The effect of glacial variation on downstream fluvial systems: Ladakh, NW Himalayas The North Sea Chalk play: non-structural traps, and increasing recovery factors from Chalk fields Late Quaternary history of the Pantanal, the largest tropical wetland on Earth Neural Networks with an Application to Global Crustal Structure

Natural Analogues for Geological Storage of CO2 The Stability of Continuous Cover Forestry Exploration of the Barmer Basin, Rajasthan, India, 2005-2006 - A Personal Perspective Agent-based modelling in agricultural policy Seismic Interferometry: From the lab to the field

Speaker Jonathan Butler Jinghua Zhang Tim Kinnaird Bärbel Traub Zainuddin Yusoff

Isabel Varela Huw Jones Adrian Tuitt John Dowens Johan Robertsson

Gillian McCay Guy Hall Andrew Casely Caroline Graham Richard Taylor

Gail Millin Zhongping Qian Natalie Starkey Nick Cutler Hannah Suttill

Ciaran Beggan Caroline Gill Zana Conway Kevin Jones Kevin Welsh

Adam Wilson Daniel Hobley Joan Megson Bronwen Whitney Ueli Meier

Jiemin Lu Axel Wellpott David Bailey Conrad Rider David Halliday

Session

1 Great Glen

2 Loch Ness

3 The Dalradian

4 The Moine

5 Black Isle

6 Eathie

7 Ben Wyvis

Dinner Menus

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Dinner Menus

Friday Night

Venison Pate wrapped in Bacon served with Redcurrant Jelly and Oatcakes

Black Pudding Clap shot Cake served with a Wholegrain Mustard Sauce

Hot Tomato and Onion, Cotswold Cheddar tartlet, Caramelised Onion topped with Cheese on a Puff Pastry then baked with Curly Endive salad

Smoked Haddock, Sweet corn and Tomato Chowder

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Lemon Sorbet ******

Roast Honey Glazed Gammon served with a Caramelised Pineapple and a

Wholegrain Mustard Sauce

Pan Fried Chicken breast wrapped in streaky bacon with a White Wine sauce

Fillet of Salmon topped with a Herb crust placed on a bed of Creamed Leeks

Stir fried Vegetable Enchilada

Cold Cuts with Seasonal salad

******

Toffee Cheesecake with Whipped Cream and Chocolate Sauce

Warm Pancakes topped with Ice cream and Warm butterscotch Sauce

Fresh Fruit Salad

Selection of Ice cream

Dinner Menus

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Saturday Night – GradSchool Conference Banquet

Prawn and Avocado Cocktail served on a Chiffonade of Lettuce with a Marie Rose dressing

Chicken Liver Pate laced with Brandy and Redcurrants with a Salad Garnish and

Melba toast

Fan of Honeydew Melon with a Spiced Winter Fruit and Raspberry

French Onion Soup

****** Mango Sorbet

******

Roast Leg of lamb seasoned with a Black pepper and Rosemary Crust served with

Pan Gravy

Pan fried Chicken Breast stuffed with Haggis drenched with a Whisky Cream Sauce

Fillet of Lemon Sole rolled with a Salmon Mousse lightly Poached and served with a Seafood Sauce

Oven Baked Capsicums filled with Risotto and Rice topped with Coriander Cheddar

Cheese Crumb

Cold Cuts with Seasonal Salad

******

Chocolate Profiteroles in a hot Fudge sauce topped with Whipped Cream

Sticky Toffee Pudding with Ice cream or Cream

Brandy Snap basket filled with Ice cream drizzled with Raspberry sauce

Selection of Ice cream

Abstracts: Session 1

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Abstracts Session 1: Great Glen The Great Glen marks the location of a major strike-slip fault running SW-NE for over 100km between Fort William and Inverness, continuing westwards into the Atlantic and northeastward towards Shetland offshore. The fault was active by the Devonian and is still seismically active today, occasionally producing earthquakes up to Magnitude 4 in intensity. It divides the predominantly Moine rocks of the Northern Highland Terrane from the Dalradian rocks of the Central Highland Terrane to the south. Quantifying the evolution of the Orange River basin, South Africa: new erosion rate data from terrestrial cosmogenic nuclides Jonathan J Butler Institute of Geography The Orange River is one of the world’s major drainage basins, covering an area of some 890,000 km2. Documenting its evolution is key to understanding the long-term geomorphic history of a significant proportion of the southern African landmass. The Augrabies Falls is a major knickpoint on the Orange River and effectively separates the landscapes of the Orange basin upstream from base level changes affecting the Orange River downstream. Quantifying the rate and style of knickpoint retreat at the Augrabies Falls is consequently crucial in unraveling how the Orange River basin as a whole has evolved. Until recently no method was available to measure directly the long-term rate of erosion of bedrock (such as that which forms the Augrabies Falls), but the development of cosmogenic isotope analysis is now making this possible. Likewise, long term erosion rates for entire basins can be determined by measuring the 10Be and 26Al concentration from detrital quartz in river channels. Erosion rate data which helps unravel the evolution of the Orange basin is presented. In the Augrabies Falls region, bedrock erosion rates are highest in tributary channels, which track changes in the local base level. This data allows the evolution of the main river channel to be reconstructed and the role of extremely high magnitude flood events to be assessed. There is considerable variation in basin-wide erosion rates on different spatial scales reflecting different local factors such as lithology, basin morphology and long-term land use. The possibility of using basin-wide erosion rates to ‘benchmark’ long term (103-105yr) erosion rates against contemporary rates as part of integrated land management plans is considered.


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Multi-Component AVO Inversion Jinghua Zhang¹ ², Xiangyang Li² and Fabio Mancini ³ ¹ Institute of Earth Sciences ² British Geological Survey ³ Total We have developed an approach that uses a weighted stacking technique to invert elastic impedance reflectivity from PP- and PS-waves. The weighting parameters are angle-dependent. In single PP-wave inversion, the weights for ∆Is/Is distribute mainly in both the near and far offsets; while for ∆Ip/Ip the weights decrease with the increasing offset. In joint inversion, though the near offset PP-data and mid-offset PS-data contribute more weights for both ∆Is/Is and ∆Ip/Ip estimation, the mid-offset PS-data have a larger impact on the estimation of ∆Is/Is. Incident and reflection angles, and Vp/Vs ratios are calculated from ray tracing. For S-impedance reflectivity inversion, noise-free synthetic PS-data alone gives the most accurate result. For S-impedance reflectivity inversion from PP-data, sufficient offsets should be included for an accurate inversion, because the far offset contributes a large weight for S-impedance. Joint PP- and PS-inversion improves the S-impedance reflectivity accuracy compared to PP-data alone, especially when noise is present in data. For P-impedance, PP-data alone or joint inversion leads to a similar result. This study confirms that the smoothed velocity-depth model does not have much effect on inversion results. The above findings are applied to two real data study cases. In both synthetic examples and 2 cases studies, the joint inversion produces a better estimation of the shear impedance reflectivity and of the pseudo Poisson’s ratio reflectivity compared with the single inversion.


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A magnetostratigraphy for the raised beach deposits of southern Cyprus: Early Pleistocene – Recent uplift of the island of Cyprus Tim Kinnaird Institute of Earth Sciences Fieldwork and aerial photography show that raised beach deposits (hereafter marine terraces), channel fans and river terraces occur systemically throughout southern Cyprus, a result of the uplift of the island being centred on the Troodos Massif. In the early nineties, Poole and Robertson recognised and correlated five distinct marine terraces; the late Pliocene-early Pleistocene - F0 terrace; the early-mid Pleistocene – F1 and F2 terraces; and the late Pleistocene F3 and F4 terraces. Corals obtained from the latter terraces (F3 and F4) have been dated with the uranium-series method (Poole and Robertson, 1990); yielding ages of 185-192 ka and 116-130 ka respectively. When correlated with the global isotope stages, the results suggest that southern Cyprus has been uplifted 18 metres during the last 185-192 ka, at approximate rates of 24 cm/ka between 130 and 185 ka and 5 cm/ka between 116 ka and the present. Whilst this work has constrained the tectonic history of recent uplift, it has shed little insight onto early Pleistocene uplift. To date, there are no age constraints for the older marine terraces (F0 - F2), or any of the younger alluvial channels. The present study was initiated to find the mid-early Pleistocene reversal (c. 0.78Ma), presumably in either the F1 or F2 terraces, in an attempt to better constrain the timing and mode of uplift for this period in Cyprus’s history. In addition, it is hoped to correlate the marine and alluvial terraces.


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Research at 63°23’ North Bärbel Traub SINTEF Petroleumsforskning AS The SINTEF Group is one of Europe’s largest independent research organizations. One of its divisions is SINTEF Petroleumsforskning AS which comprises the departments of seismic, formation physics, reservoir engineering, basin modelling, multiflow technology, and well and production technology. The range of activities in the seismic department go from OBS (Ocean Bottom Seismic) depth migration, AVO, 4D, seismic modelling to inversion. One of the main projects in the seismic department is the development of a quantitative depth imaging sequence for ocean bottom seismic data. This project combines expertise from several disciplines, working on the development of processing and analysis methods for seismic data acquired at ocean bottom by nodes or by cables technology. This data allows the recording of vector wave fields; the full exploitation of these should provide better images of the subsurface. Therefore, the description of the reservoirs should be more accurate and the production control should be more effective.


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Weathering of minerals in granite in the tropics Zainuddin MdYusoff Institute of Earth Sciences Chemical weathering of granite under tropical conditions can produce up to 40m of laterite. Of all the minerals present in the granite studied, feldspar dissolution is a key process in laterisation. To understand the mechanism of feldspar weathering under such conditions, detailed investigations involving mineralogical, geochemical and micro-structural characteristics of weathering profiles, including the underlying unweathered granitic rocks, at two locations in Malaysia were conducted. Recently exposed and drill hole samples were investigated. It was found that the dissolution of feldspars almost all occurs over a 1 to 2m thick zone at the weathering front between rock and laterite. In alkali feldspars dissolution of albitic perthite lamellae occurs first, initially at misfit dislocations. At an advanced stage, the albite lamellae dissolve completely and the K-feldspar grains collapse. The first main product of feldspar weathering is halloysite.


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Session 2: Loch Ness Loch Ness is the second deepest loch in Scotland (after Loch Morar), and the largest by volume. Glacial scouring produced a trough so steep that aquatic vegetation is almost absent. Loch Ness forms part of the only route by which it is possible to sail from east to west across Britain. The Caledonian Canal, completed in 1822, links Loch Ness with Loch Oich and Loch Lochy, connecting with Loch Linnhe at Fort William in the west. Fluid and anisotropy effects in porous rocks from seismic time lapse data Isabel Varela¹ ² ¹ Institute of Earth Sciences ² British Geological Survey As reservoir fluids change, so do the elastic moduli of the rock and its acoustic properties or impedances, which seismic data are sensitive to. Hence, seismic anomalies in time-lapse data may be indicative of reservoir changes due to varying pore fluids. As seismic waves travel through the earth part of the energy is converted to heat due to the anelastic behaviour of the rocks. This loss in energy known as anelastic attenuation will depend on various factors including the composition and structure of the rock, its saturating fluids and the temperature and pressure conditions at which they are subjected, whereupon attenuation analysis will be a key factor in investigating fluid changes and fracture properties from seismic data I present analyses of two time lapse 3D 3-component, multilevel vertical seismic profiles (VSP's) data sets from the Weyburn field, Canada, which has undergone CO2 injection for enhanced oil recovery, and the Qarn Alam field in Oman, which has a long history of steam injection and production. I show through the two data sets, the potential of azimuthal travel time and attenuation studies of P-waves for fracture characterization. Velocities and attenuation are sensitive to the fracture network, presenting shorter travel times and lower attenuation in the direction of the fracture plane.


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Characterisation of Neotropical Savanna Ecosystems by their Modern Pollen Rain Huw Jones Institute of Geography There is currently large uncertainty about the response of Amazonian ecosystems to environmental changes in the Quaternary. An understanding of past vegetation dynamics is important to predict the response of these ecosystems to future global change and also refine theories concerning Amazonian speciation. However, there is debate among researchers about the degree to which forest ecosystems were replaced by more open, savanna ecosystems during the last glacial maximum. These interpretations are based on fossil pollen records and are hindered by a poor understanding of Neotropical palynology. The study of the modern pollen rain of different ecosystems can improve the interpretation of fossil pollen records by providing modern analogues for these fossil pollen records. Therefore, the aim of this research is to characterise the modern pollen rain of two savanna ecosystems and the degree to which they may be differentiated from each other. These two ecosystems are an upland terra firma savanna and a seasonally-flooded savanna. These ecosystems occur under different environmental conditions, so inferring the type of savanna will be important for palaeoecological interpretations. The study site is Noel Kempff Mercado National Park in Bolivia, in the south-west of Amazonia. Artificial pollen traps and surface lake sediments from each type of savanna will be used to sample the modern pollen rain and sampling will allow both intra-site and inter-site variability to be studied. Vegetation plot data will allow modern pollen-vegetation relationships to be defined. These results will then be available to improve the interpretation of fossil pollen records from the region.


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Controls and timing of structural inversion in the NE Atlantic Margin Adrian Tuitt¹ ² ¹ Institute of Earth Sciences ² British Geological Survey Cenozoic compressional features, such as folds and reverse faults, are found in the NE Atlantic Continental margin. The area of study includes the Rockall Plateau, the Rockall Trough and the Wyville Thomson Ridge Area. Many authors attribute these compressional structures to the opening of the Atlantic (ridge push) and to Alpine compression (Boldreel and Andersen, 1998). However, the timing of these structures is poorly constrained. Therefore, it is difficult to link their formation to regional events. 2D seismic data for the study area has revealed, in addition to anticlines, unconformities characterised by onlap, downlap, erosional truncation and toplap. The timing of folding can be determined using the ages of unconformities constrained using well data. Some unconformities may be the result of changes in bottom-water current activity (Stoker et al., 2001). This could have resulted from bathymetric changes caused by compression. However, until the timing of compressional events is more precisely constrained, the link between bottom-water current activity, compression and regional events cannot be established. Underplating, which characterises volcanic margins, results in uplift and thus may play a role in the formation of certain unconformities. Pre-existing structures could have made Cretaceous (syn-rift) and Cenozoic (post-rift) sediments prone to the effects of compression. For example, half graben structures facilitate inversion of syn-rift sediments and the folding of overlying post-rift sediments, whilst seamounts or underplated igneous material could have had a buttressing effect. Anticlines may also be the result of transpression along stike-slip lineaments (Dore et al., 1996). The nature, orientation and timing of all compressional structures in the study area are critical in establishing their compressional mechanisms. References:

Boldreel, L.O. and Anderson, S. 1998. Tertiary compressional structures on the Faeroe-Rockall Plateau in relation to northeast Atlantic ridge-push and Alpine foreland stresses. Tectonophysics, 300, 13-28.

Dore, A. G., and Lundin, E. R., 1996. Cenozoic compressional structures on the NE Atlantic margin: nature, origin, and potential signficance for hydrocarbon exploration. Petroleum Geoscience, 2, 299-311.

Stoker, M.S., Van Weering,T.C.E., and Svaerdborg, T., 2001. A Mid-to Late Cenozoic tectonostratigraphic framework for the Rockall Trough. In: Petroleum Exploration of Irelands Offshore Basins. Special Publ. Geol.Soc., Vol. 188, 411-438.


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Remote Sensing of Peatlands: Classification of Blanket Bog Microhabitats using Spectral Library, Lidar and Hyperspectral Data John Dowens Institute of Earth Sciences Blanket bog is a globally rare peatland type, occurring only in temperate oceanic climes where regular rainfall results in a mantle of peat covering large tracts of land. Scotland contains about one million hectares of blanket bog, representing approximately 10% of the total, and including some of the largest and most undisturbed areas of this habitat in the world. Blanket bogs play an important role in the carbon and hydrological cycles, and are considered to be of high conservation value. Globally, peatlands are responsible for approximately 40% of natural methane emissions, contain up to half of soil organic carbon reserves, and have the potential for strong feedbacks on the climate due to the fine balance between them being sinks or sources of carbon. In the UK, and throughout the world, peatland sites are threatened by changes in land use, pollution, and climate change. The effects of these threats and the response of peatlands to them is observable by shifts in fine scale hydrology and surface structure, such as the relative abundance and distribution of microtopographic elements, or changes in vegetation composition. To accurately monitor the current state of blanket mires, and to observe the effects of environmental change on them, we must survey them at the scale of surface microforms. Given the size and remote nature of many peatland sites, this is too large a task for regular ground survey. Blanket bog is therefore an ideal target for remote sensing methods.


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Prestack depth migration of primary and surface-related multiple reflections Remco Muijs¹, Johan Robertsson² * and Klaus Holliger ³ ¹ ETH-Zurich ² WesternGeco ³ University of Lausanne So-called surface-related multiples (energy reflecting off the sea-surface one or several times before being recorded) may severely contaminate seismic recordings. Because conventional imaging techniques require input data that consist of primary reflections only, significant processing effort is commonly dedicated to attenuating multiples prior to migration. On the other hand, surface-related multiples provide additional illuminations of the subsurface. We present a prestack depth migration method that allows primary and multiple reflections to be imaged simultaneously. Depth imaging with primary and multiple reflections (DIPMR) involves decomposing the data into up- and downgoing wave constituents, followed by downward extrapolation. Artifacts generated by interference of up- and downgoing events not associated with the same subsurface reflection points (cross-talk) are attenuated using a 2D deconvolution imaging condition. In contrast to existing methods, DIPMR does not require a priori information about the source signature or directivity, because the illuminating source wavefield is extracted directly from the data themselves via the up/down separation. Moreover, there is no need for elimination or identification of multiples prior to migration. By including surface-related multiples in the imaging procedure, the effective source wavefield is stronger and the spatial aperture wider.


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Session 3: The Dalradian The Dalradian Supergroup of the Central Highlands Terrane, a sequence of metamorphosed marine sediments and volcanics, was deposited between approximately 800 Ma and 500 Ma. The group was affected by the Grampian Orogeny (the initial stages of closure of the Iapetus Ocean) during the early to mid- Ordovician. The present juxtaposition with the Northern Highland Terrane is due to major movements along the Great Glen Fault. An integrated study of the role of distributed deformation in the collision of continents (Kyrenia Range lineament, Northern Cyprus) Gillian McCay Institute of Earth Sciences The eastern Mediterranean Sea marks the site of a number of small ocean basins that were created, and then largely destroyed, along the northern margin of Gondwana. Between the late Cretaceous and the middle Eocene, three of these smaller tectonic units were juxtaposed and finally amalgamated into the island of Cyprus. Evidence of this amalgamation is well preserved in the Kyrenia Range, located in the north of Northern Cyprus, and is the area on which this research project focuses. Two weeks of preliminary field work have been undertaken in this region. Further field excursions are planned for mid-January and March. The Kyrenia Range is a narrow, arcuate lineament several hundred kilometres long and encompasses both Northern Cyprus and its offshore extension. The range consists mostly of Mesozoic and Tertiary sediments with subordinate volcanic and metamorphic rocks. The succession is divided into four rock groups (Trypa, Lapithos, Kithrea, Mesaoria) separated by unconformities that record deformation events. The project will study the sedimentary successions in the region in an attempt to discover and identify the:

1. Basinal settings that were present during the deposition of the major rock formations

2. Reasons for local variations in Miocene rock types between the north and south sections of the Kyrenia range

3. Cause of thrusting and large scale deformation events and their influence on the infill of the basin

Other investigation will include estimating the duration of uplift and whether the uplift was continuous or pulsed. The final results from this research will be of importance to Northern Cyprus, with implications for both water resources and earthquake hazards.


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MTEM: Shallow Marine Trial Guy Hall¹*, Anton Ziolkowski¹, David Wright¹, Richard Carson¹ ¹ MTEM Ltd. MTEM (Multi Transient ElectroMagnetism) can discriminate between water and hydrocarbons in a reservoir. Applications include exploration, monitoring fluid movement in known reservoirs and location of by-passed hydrocarbons in mature fields. The method has been demonstrated on land in Europe and North America. We present results of a marine trial to demonstrate the potential for application of MTEM in the marine environment. The setup consisted of a 10-channel receiver cable, 2 km long, laid on the sea floor and connected to an on-board recording system with real-time quality control. A current source, also on the sea floor, was connected to a second vessel. Water depth was 15 m. Timing on the two vessels was synchronised using GPS. The source time function was a pseudo-random binary sequence and the emitted source current was measured. Each receiver channel measured the potential difference between electrodes 200 m apart along the cable. The source electrode spacing was also 200 m in the same line. Signals were recorded at offsets of 400 m to 8 km, corresponding to target depths of about 200 m to more than 2 km. Recovered earth impulse responses correspond with those obtained by modelling over the known geology, the structure and resistivities of which were constrained by offshore seismic data tied to known horizons and onshore well logs.


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Good for glaciers, bad for people? Disentangling the twin effects of climate and human impact in Norse Iceland Andrew F. Casely Institute of Geography A key question in palaeoenvironmental science is the extent to which climate has played a role in environmental and cultural change. Many palaeoenvironmental indicators (e.g. pollen, coleoptera and diatoms) are used both as palaeoclimate / palaeotemperature indices and indicators of anthropogenic impact. They are frequently unable to clearly distinguish whether the recorded change is natural or anthropogenic. Independent indicators such as ice cores or marine sediments are generally located far from sites of archeological interest. This is a key question in our understanding of the extent to which humans have been responsible for episodes of land degradation or vegetation change in the past, or if such episodes were caused by natural climate change. In Iceland we may separate out these two causes of impact by combining evidence gathered from glacier changes with modelling experiments from a new high resolution climate and degree-day vegetation model of Iceland. The model is constrained by observed glacier mass balance and equilibrium line altitudes, and is used to predict potential vegetation cover for given temperature changes. In Thórsmörk, south Iceland, modelling indicates that climate is not responsible for the observed deforestation and land degradation, and that woodland preservation is a result of Norse land management. In the Mývatn region, rangelands connected with inland farms are less productive and more sensitive to changes in growing season length and snowcover, with the implication that land degradation in the area has been substantially exacerbated by natural cooling on the scale of the Little Ice Age.


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Acoustic emissions as an indicator of damage Caroline Graham¹ ² ¹Institute of Earth Sciences ²GeoForschungsZentrum Understanding the processes involved in the deformation and brittle failure of composite materials is of major importance in a number of fields, including seismology, hydrofracture and stability assessment in civil engineering. Laboratory studies of brittle fracture can yield significant information about such deformation. The growth of microcracks within a deforming rock can produce high frequency acoustic emissions (AE). These emissions have been shown to correlate with strain rate. AE events can, therefore, be recorded during loading of rock samples and the resulting data used as an indicator of damage rates. There is a large overlap between the study of acoustic emissions and seismology. Earthquakes and AE exhibit similar statistical behavior, indicating that these phenomena may involve similar source processes but on different scales. By applying techniques commonly used in seismology, the location and source characteristics for individual AE events can be determined, giving information about the associated mechanisms, distribution and propagation of damage within samples prior to brittle failure. This project will involve the application of such methods to experimental data, collected in Edinburgh and at the GeoForschungsZentrum in Potsdam. The effects of deformation localisation will be investigated, with the aim of developing a predictive model for rock failure on laboratory scales.


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The Kerala Khondalite Belt: A Natural Laboratory for Crustal Melts Richard Taylor Institute of Earth Sciences In the field of U-Pb geochronology, zircon remains the most important mineral in crustal rocks. It forms through many processes, both igneous and metamorphic, and its structural and chemical resilience to high temperatures and open-system effects enhances its ability to retain a compositional and isotopic memory. As such, ages obtained from zircons in crystalline rocks are commonly used to constrain the timing of major geological events. However, a key to understanding orogenesis and crustal evolution is to be able to the relate age data from zircon to specific rock and mineral processes. Integral to this aim is to understand the behaviour of Zr during metamorphism, and the formation of zircon in relation to well-constrained metamorphic reactions and conditions. Understanding such processes improves our ability to place zircon-derived isotopic ages in a realistic metamorphic, and therefore orogenic context. Identifying the timing of prograde, peak and retrograde metamorphism in high-grade terrains can be problematic. Zircon is an accessory mineral often forming from the breakdown of Zr-bearing phases, which may occur in granulites at various stages on a pressure-temperature path. It is therefore of great importance to understand exactly when, where and how zircon is able to form and break-down, but also ‘survive’ intense geological conditions. The high-grade gneisses of the Kerala Khondalite Belt, southern Peninsula India, provide natural examples of the formation of zircon during high-grade metamorphism. An integrated study of the textural and chemical relationships of zircon with other major and accessory minerals will help provide a framework for interpreting age data from high-grade terrains and an improve our understanding of geological processes and events.


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Session 4: The Moine The Moine Supergroup is the major constituent of the Northern Highland Terrane. Marine sediments were deposited from approximately 1000 to 870 Ma, and subsequently metamorphosed into pelites during closure of the Iapetus Ocean (the Grampian Orogeny). An earlier phase of deformation may have occurred, but the tectonic history of this terrane remains controversial. The UK Satellite Image Data Service hosted at MIMAS – Providing Remote Sensing Products and Learning Resources for UK Academia Gail Millin MIMAS, Manchester Computing, The University of Manchester Manchester InforMation and Associated Services (MIMAS) provide a range of services for UK academia, one of which is the UK Satellite Image Data Service. The service is funded by Joint Information Systems Committee (JISC). We now provide a range of satellite imagery to UK academia. The service provides the deliverables of the ‘Landmap Project’ which was in collaboration with UCL Geomatics Department. The project produced a complete coverage of the UK of orthorectified Landsat, SPOT and ERS radar data; a 25m DEM was derived from SAR interferometry and a GPS survey, which was used for quality assurance. Recent projects at the service included the JISC funded Geodata Interoperability Project aimed at providing the service satellite products in an OGC compliant format (WMS &WCS). As a result an interactive mapping interface is being developed to provide a more dynamic way for our users to download and access the data. The range of satellite products provided by the service is constantly increasing. Acquisition and processing of European Space Agency ASAR data is underway for Wide Swath, Image Mode and Alternating Polarisation data. The Radar data acquisition will consist of a set of ASAR imagery acquired over a period of time for UK coverage in an orthorectified geotiff format. For subscribed institutions to the service a 10 module on-line image processing course has recently been made available at no additional cost. The course is ideal for students starting out in the field of remote sensing and has been adapted for a range of image processing software’s (ERDAS Imagine, PCI, Idrisi Kilimanjaro and ENVI).


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3D physical modelling for fracture characterisation Zhongping Qian¹ ² ¹Institute of Earth Sciences ²British Geological Survey This study is to verify the physical basis of using P-wave attributes for fracture detection, to understand the usage of these attributes and their merits, and to investigate the effects of acquisition geometry and structural variations on these attributes. The basic model consists of a fractured layer (artificial limestone) sandwiched between two isotropic layers (Epoxylite). Inside the fractured layer there is a dome and a fault block for investigating the effects of structural variations. The two experiments were carried out using different acquisition geometries. The first experiment was conducted with a water layer of 1470m on top, leading to an overburden as thick as 1962m. This experiment was designed to maximize the data quality, which ensures the arrivals from the top and bottom the fracture layer are free of the interference of multiples. For comparison, a second experiment was carried out with the thickness of the overburden reduced to 932m, and the offset-depth ratio to the top of the fracture layer raised to 2.2, which maximizes the anisotropy effects. The physical modelling confirms that the P-wave attributes (traveltime, amplitude and velocity) exhibit azimuthal variations diagnostic of fracture-induced anisotropy. For the first experiment with noise-free data, the amplitude from the top of the fracture layer yields the best results that agree with the physical model parameters and free of the acquisition footprint. The results from other attributes (traveltime, velocity, AVO gradient) are either contaminated by the structural imprint, or by the acquisition footprint due to the lack of offset coverage. For the second experiment, despite the interferences from multiples and other coherent noise, the traveltime attributes yield the best results; both the acquisition footprint and the structural imprint are reduced due to the increased offset coverage. However, the results from the amplitudes are affected by the noise and are less reliable.


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Plumes and Picrites – a hot topic! Natalie Starkey Institute of Earth Sciences Magmatism in the North Atlantic Igneous Province (NAIP) is thought to be related to the presence of a mantle plume initially impinging on the lithosphere at ~60Ma. Early magmatism associated with the plume occurred prior to continental break-up producing picrites outcropping across a large region from Baffin Island to the British Tertiary Igneous Province. Picrites are characterised by high MgO (typically over 12 wt%) resulting in a large olivine content and are thought to indicate eruption of hotter-than-normal magmas at the Earth’s surface. Mantle plume theory predicts that the products of plume magmatism will be ‘primitive’ compared to rocks produced at other geological settings as plumes are thought to rise from the core mantle boundary being thus composed largely of primordial lower mantle material. This means that the rocks should be relatively enriched in incompatible elements (those elements that are depleted during melting events) and also rich in 3He. 3He is not produced in the Earth so its presence in the Earth today is related to the amount of 3He left over after degassing during Earth accretion and degassing from volcanoes. Recent research involving picrites from Baffin Island (Stuart et al., 2003) suggests that those rocks with high 3He/4He appear to be the most depleted in incompatible elements despite mantle plume theory predicting that they should be the most enriched. Depleted rocks are generally associated with mid-ocean ridges and these are found to exhibit low 3He/4He as they are thought to be the product of melting of the depleted upper mantle. Therefore, the geochemical signature of the Baffin Island rocks may be related to recharge of the depleted upper-mantle by primordial helium brought up from the lower mantle by a plume (Stuart et al., 2003). Referecnes: Stuart, F.M., Lass-Evans, S., Fitton, J.G. and Ellam, R.M. (2003). High 3He/4He in

picritic basalts from Baffin Island and the role of a mixed reservoir in mantle plumes. Nature 424, 57-59.


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Ecosystem development on the historical lava fields of Mt. Hekla, Iceland Nick Cutler Institute of Geography A rare combination of volcanological, biogeographical and historical factors render Mt Hekla a natural laboratory for the study of long-term (decades to centuries) ecosystem development. This study focuses on spatial and temporal changes in vegetation and soil properties on historical (post 10th Century AD) lava flows around the volcano. Long-term trajectories of development have been inferred from an 800-year chronosequence comprising 7 historical lava flows. Tephrochronological studies indicate that these flows have been largely unaffected by the deposition of tephra (volcanic ash) in the historical era. A further 5 lava flows that have been significantly impacted by tephra fall were also sampled for comparison. Plant species abundance, soil depth and surface profile were sampled at each survey site. The data gathered were analysed using geostatistical techniques to assess changes in spatial patterning. Diversity indices were also calculated for each of the sites. The initial results of the analysis indicate that it is possible to identify a clear pattern of development across the chronosequence; furthermore, disturbance by tephra deposition appears to increase vegetation diversity and is likely to play a significant role in determining the spatial structure of the plant assemblages present. Future work will concentrate on identifying the ecological and environmental processes that drive ecosystem development on the lava flows, and assessing in detail the impact of tephra deposition.


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Development of the Balkan Fold-and-Thrust Belt Retro-Thrust wedge: evidence from the Western Black Sea and Eastern Bulgaria Hannah Suttill Institute of Earth Sciences Mountain belts are inherently asymmetric, defined by the sense of subduction. The resultant orogen can be divided into a pro- and retro-wedge with the retro-wedge overlying the overthrust plate. Modelling suggests that retro-wedges and their neighbouring foreland basins have very specific controls on orogen development that have not previously been recognised. This study on the Balkan Mountains will synthesise data from 3D seismic surveys and core from the Western Black Sea, with outcrop fieldwork in Eastern Bulgaria, to investigate orogenic and petroleum systems development during orogenic evolution. In addition to thorough basin analysis, it will be possible to obtain high resolution timings of thrusting and associated sedimentation through a combination of sequence stratigraphy, sedimentological study and biostratigraphy. The high quality and availability of data is unique for this tectonic setting and will potentially provide insight into other retro-wedge systems such as the Aquitaine Basin. The E-W trending Balkans are the collisional product of the late Mesozoic/early Cenozoic Alpine Orogeny. Situated north of the deformation front, the Stara Planina Frontal Thrust, and south of the Moesian Platform, is the Palaeocene-Mid Eocene, deep-water Dolna-Kamchia Basin. These components together comprise the retro-thrust wedge and foreland basin of the Hellenide-Balkan belt, situated on the overthrust plate of the northerly-plunging Eurasian-Anatolian subduction zone. Subsequent to the growth of the Balkans, the extensional opening of the Black Sea by end Miocene transected the E-W trending fold-and-thrust belt structures by a series of N-S trending normal faults. Consequently, the well-exposed Bulgarian coastline is oriented perpendicular to strike of the Balkans thus providing an ideal opportunity for detailed onshore study across the entire retro-wedge.


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Session 5: Black Isle The Black Isle is a predominantly agricultural peninsula lying between the Moray and Cromarty Firths. The town of Cromarty, in the northeast corner of the Black Isle, hosts the former home of Hugh Miller, the stonemason who became a foundingfigure of geological science. The Black Isle is home to a large population of Red Kites, which were successfully reintroduced to the area in the late 1980’s after being hunted to extinction by the mid- 19th century. Predicting Secular Variation using Core Flow Models Ciaran D. Beggan Institute of Earth Sciences The Earth's magnetic field is generated by fluid motion of liquid iron in the outer core. Secular variation (SV) is the phenomenon by which the Earth’s magnetic field changes slowly over decadal timescales. Flows (on the order of 10km/yr) at the top of the outer core are believed to be responsible for the secular variation observed at the surface of the Earth. However, modelling of this flow is open to considerable ambiguity. Mathematically, relating the magnetic field to the flow of the liquid iron is a ‘non-unique’ problem; i.e. there are an infinite number of possible flows which fit the magnetic field changes observed at the Earth’s surface. To overcome the non-uniqueness problem, geophysicists use physical constraints on the magnetic field (e.g. total strength) and the flow regime (e.g. fluid dynamics) to reduce the problem to a more manageable one. Interestingly, computer models that use different physical assumptions for the magnetic field and outer core give rise to similar flow velocities, though they often differ in detail. The aim of the project is to develop methods that predict the SV more precisely than previous methods (such as non-linear extrapolation or spline curve fitting). This project will investigate the use of different ‘best-fit’ or ‘minimisation’ methods with core flow models, to produce a better prediction of the time evolution of the field. This can be used to produce more accurate magnetic field maps for use in marine navigation charts and industry (e.g. oil well drilling).


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The Nelson Field – A huge challenge for a new graduate Caroline E. Gill Shell The Nelson Field is located in blocks 22/11, 22/6a, 22/7 and 22/12a in the UK Central North Sea. Nelson is a simple 4-way dip closed structure, and is one of a series of Palaeocene Forties Sandstone Member oil accumulations situated on the Forties-Montrose High (Forties, Nelson, Montrose, Arbroath, Arkwright). The Forties Sandstone represents the primary reservoir unit in the majority of hydrocarbon accumulations situated in this region of the Central North Sea. The Forties Sandstone represents a complex submarine fan system comprising a number of phases of fan activity including outbuilding, channel switching (avulsion cycles) and eventual abandonment. Facilities on the Nelson Field include a 36 slot platform with a four well sub-sea template tied back to the platform. The production facilities have a peak daily capacity of 160,000 barrels of oil and 65 million cubic feet of gas. Total liquid capacity is 250,000 bbls. Hydrocarbon type is a light 40o API oil with a GOR of 555 scf bbl. Live crude is exported via Forties to Cruden Bay and gas is exported to the Fulmar Gas Pipeline via Kittiwake to St Fergus. Nelson also provides production and processing services for the Howe Field via a 14km sub-sea tie-back. The key geoscience challenges associated with the Nelson Field today are the strategic location of new in-fill wells to locate and produce oil stranded within the reservoir, or to accelerate production. First oil was produced from the field in March 1994, and peak production was obtained early in the field life. The large and relatively easy channel-axis targets associated with the Nelson Field have all been drilled and as a result more difficult and subtle targets are needed in order to maintain economic production of the field. These remaining targets are structurally and sedimentologically difficult to resolve on seismic data and as such new and innovative approaches are necessary in order to characterise and realise the remaining production potential on the Nelson Field. Identification of these targets requires an integrated understanding of both the static data associated with the reservoir, for example the rock properties, and also the dynamic data, such as production rate and connectivity, in order to determine where oil remains in significant accumulations within the subsurface.


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The Origin of the Silverpit Structure; The Truth is Out There… Zana Conway¹ *, Stuart Haszeldine¹ and Malcolm Rider ¹ ¹ Institute of Earth Sciences The origin of the 20km diameter Silverpit structure has been contested since its discovery in 2002. Although its structural geometry suggests a meteorite crater, no definitive evidence is available to confirm the origin of the structure. Rival explanations include salt withdrawal and mud diapirism. As no direct drilling of the structure has taken place, there is a lack of rock material to carry out mineralogical and geochemical analysis to confirm the meteorite crater hypothesis. Consequently other methods have been developed, which although not conclusive, may bring convergence on an explanation for this structure. Two principal data sets have been used, 3D seismic data covering 7000km2 of the southern North Sea basin and over fifty geophysical well logs throughout the same area. Analysis of this data has highlighted that Silverpit is without doubt a unique structure in the area of the southern North Sea studied. The well logs also confirm that the structure has very unique properties, with unusual compaction trends in the Cretaceous chalk, stratigraphically beneath Silverpit. As the search for more conclusive evidence, either mineralogical or geochemical, continues in vain, it is important to ask one question: What process causes the formation of a unique, circular feature, with a conical central uplift, internal zone of deformation and concentric ring faults surrounding the centre, along with unusual compaction in the stratigraphy beneath the structure? If this can be answered, perhaps the origin of the Silverpit structure is not such an enigma.


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Measurement of advection and surface-atmosphere exchange in complex terrain Kevin H. Jones Institute of Atmospheric and Environmental Science Concern has been expressed in the eddy covariance literature (Raupach and Finnigan 1997, Finnigan, 2003, Katul et al, 2003) that drainage advection effects are a significant problem (causing error magnitudes of the order of 100% of signal) for the global eddy covariance tower network (FLUXNET) since many of these flux stations are in areas of hilly terrain. The purpose of this research study is to investigate how advection, assumed to mainly take the form of katabatic drainage at night, affects eddy covariance measurements of vertical gas exchange between the soil/vegetation and the atmosphere. Mahrt et al. (2001) have described how thin night time drainage flows (less than 3 metres thick) can form over gently sloping (5 degrees) gully systems in open countryside preventing flux towers from estimating or even detecting night time plant respiration fluxes of CO2 into the atmosphere from the surface. This study is an attempt to detect and quantify similar katabatic flows and associated advection fluxes of scalars (such as CO2) underneath temperate forest canopies on gently sloping terrain (2 to 5 degrees), and the effects such flows have on eddy covariance measurements of CO2 and other scalar fluxes measured on a conventionally situated flux tower above the canopy. My objective is to quantify how sub canopy katabatic flows effect conventional flux tower measurements of net ecosystem exchange (NEE) of CO2 and other fluxes between the land and the atmosphere. References: Finnigan, J, J., 2003. A Re-Evaluation of Long-Term Flux Measurement Techniques,

Part 2: Coordinate Systems. Bound-Lay. Meteorol. Mahrt, L., Vickers, D., Nakamura, R., 2001. Shallow Drainage Flows. Bound-Lay.

Meteorol, 101: p 243-260. Katul, G., Finnigan, J.J., Leuning, R, and Belcher, S. E., 2003. The influence of hilly

terrain on canopy-atmosphere carbon dioxide exchange. Q.J. Roy. Meteorol. Soc. Raupach, M. R., Finnigan, J. J., 1997. The influence of topography on meteorological

variables and surface-atmosphere interactions. J. Hydrol, Vol 190, p182-213.


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Investigating the State of Western Warm Pool of the Tropical Pacific during a perturbed thermohaline circulation. Kevin Welsh Institute of Earth Sciences The last glacial climate was punctuated by a number of abrupt climatic events: the Heinrich Events. These are associated with reduced North Atlantic Deep Water (NADW) formation, rises in sea level of between 10 and 30m and are known to have had global climatic impacts. These rises in sea level created accommodation space for coral reefs to grow vertically. In Papua New Guinea, rapid uplift along the coast of the Huon Peninsula (up to 4m/ 1000 years) has caused these reefs to be uplifted and sub-aerially exposed. The reefs have been extensively dated and some of the reefs have been shown to be coeval with Heinrich Events. Therefore, these terraces present unprecedented opportunities to investigate the climate of the Western Warm Pool during a reduced NADW formation. The reefs at Huon contain abundant, well preserved Tridacna sp., which can be found in their growth position overgrown with coral. Tridacna sp. are long lived (10-60 years) reef dwelling bivalves. They secrete aragonite in annual growth bands, which unlike corals, have been shown to precipitate in isotopic equilibrium with sea water. As a consequence they are excellent recorders of average climate in palaeo-reefs. Here we present records of oxygen isotopes obtained from a set of 30 fossil Tridacna sp. found in their growth position in the uplifted fossil terraces at Huon Peninsula. Oxygen isotopes of these fossil bivalves reflect temperature, the evaporation/ precipitation balance of the water in which it is precipitated and are also affected by sea level at the time of deposition. Studies of modern climate show that temperature and precipitation increase and decrease together over the seasonal and inter-annual cycle. The samples were dated using radiocarbon dating. XRD measurements and SEM imagery were used to test for diagenesis. Oxygen isotope ratios were measured from powdered samples milled across the growth banding of the clams, which represent average conditions of temperature and salinity during the life of the clam. By extracting the sea level component we found that the reefs coeval with Heinrich Events were less enriched in 18O than those that were not. Therefore, our data suggests that the palaeoclimate of the Western Warm Pool became warmer and wetter at Huon Peninsula during these periods of perturbed thermohaline circulation. If interpreted in terms of temperature alone this is the equivalent of approximately 1° C, which is 30% of the LGM/ Holocene temperature change in this area.


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Session 6: Eathie The small fishing village of Eathie, on the east coast of the Black Isle, is notable as the location of Jurassic sandstone and shale outcrops, which are found on the foreshore beneath a cliff that marks the location of the Great Glen Fault. These Jurassic outcrops contain abundant fossil plants, fish and shellfish (particularly ammonites) and were a favourite collecting ground of Hugh Miller (1802- 1856). Can Anisotropic Dispersion be used for Fluid Discrimination and Fracture Characterisation? Adam Wilson¹ ² ¹ Institute of Earth Sciences ² British Geological Survey The measurement of anisotropic dispersion offers an approach to calculating fracture and fluid properties of a hydrocarbon reservoir from both surface seismic data and borehole data. The main problem that has held back the use of this approach lies in the difficulty in separating the effect of intrinsic attenuation from other wave propagation effects, particularly short path multiples. Most previous work has focused on measuring attenuation in isotropic mediums. However, recent advances by geophysicists in spectral decomposition techniques have increased the accuracy of instantaneous frequency and phase measurements obtained from a seismogram. These improvements hold open the opportunity for geophysicists to more routinely measure attenuation. Recently, researchers have been able to observe anisotropic attenuation in vertical seismic profile (VSP) data from fractured reservoirs. It has become apparent from these studies that measuring relative values of attenuation is more reliable than absolute values of attenuation. With these advances we believe it is possible to reinforce methods for analyzing VSP’s and extend the analysis to wide azimuth surface seismic data. The overall objective is to produce robust methods for detecting and interpreting anisotropic dispersion in terms of fracture properties and fluid discrimination. This will provide geophysicists with an important new tool when characterising a reservoir.


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The effect of glacial variation on downstream fluvial systems: Ladakh, NW Himalayas Daniel Hobley Institute of Earth Sciences An understanding of long-term (>103 years) erosion rates allows us to explain the origins of the modern earth surface, and also to investigate the fundamental controls on these processes. Measurable features such as topography, erosion histories and sediment fluxes provide key constraints on models of erosion, especially on how it may be driven by climatic and/or tectonic perturbation. It has been proposed that increased Quaternary erosion is explained by global climate change. The role of glacial erosion has been recognised, but little attention has been paid to fluvio-glacial systems. Rivers downstream of glaciers possess altered hydrology and sediment properties, and have the potential to transfer these signals into the wider landscape. This study aims to examine the processes and timescales involved in fluvial erosion driven by retreating glaciers using the area of Ladakh, NW Himalaya. By analysis of digital elevation models and LANDSAT imagery combined with fieldwork, it is hoped to understand, parameterize and model the response of these rivers to glacial retreat and advance. The study may also allow investigation of the fundamental processes that drive fluvial bedrock incision in a wider context. Initial results suggest that increasing glacial influence on a river can enhance its rate of erosion, but this may be dependant upon local channel form. This in turn implicates local geological and structural histories in determining magnitude of erosive response to climate change.


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The North Sea Chalk play: non-structural traps, and increasing recovery factors from Chalk fields Joan Megson Maersk Oil The Chalk play is very important in the North Sea: Chalk fields contain many billions of barrels and will produce for many years to come. The play also gets more interesting all the time: even with 40 years experience exploring for hydrocarbons in the Chalk, we still have surprises, and are discovering new things all the time. For example, ten years ago we knew that the same Chalk unit could be either seal or reservoir, depending upon diagenetic history, and we were also aware of tilted oil-water contacts in the Chalk due to reservoir quality changes, and hydrodynamic systems. I will show an example of a large field that was discovered years ago but totally overlooked until recently: it was drilled at the crest, and assumed to be non-commercial, until further drilling years later showed that there is better reservoir down flank and a tilted oil water contact. Just a few years ago we made a startling discovery: in an extensively drilled part of the Danish sector, and surrounded by Chalk fields, a very large and totally non-structurally trapped Chalk field was found. We know that in this field the oil is actively migrating through the Chalk at the present day. This appears to be a new type of dynamic trap with important implications for the Chalk play, and other low permeability plays as well.


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Late Quaternary history of the Pantanal, the largest tropical wetland on Earth Bronwen S. Whitney Institute of Geography Presented here is the first palaeoecological study of a site in the Pantanal, the world’s largest tropical wetland, located in southwestern Brazil and eastern Bolivia. Past vegetation and climate change was inferred through pollen analysis of a sediment core from a large, shallow lake (Laguna La Gaiba) located in the western Pantanal, and bordering on the Chiquitano dry forest. Preliminary data demonstrate the Pantanal wetland, seasonally-inundated savanna and Chiquitano dry forest plant communities have varied in response to changing climate over the past ~ 60 ka. These data suggest that during the last glacial period, the landscape may have been dominated by an open, savanna vegetation, possibly due to a drier climate. Tree taxa colonized the landscape around the late-glacial, but the pioneer community appears to be very different from the modern flora. Dry forest developed in the early Holocene as evidenced by the indicator taxon Anadenanthera. A Holocene origin of the Chiquitano dry forest challenges the hypothesis that the present distribution of dry forests represents refugia of a Pleistocene dry forest “arc”. In addition, evidence of Pleistocene aridity in the Pantanal could prove invaluable to elucidating the complex, and often controversial, glacial precipitation regime of the southern neotropics.


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Neural Networks with an Application to Global Crustal Structure Ueli Meier University of Utrecht Nonlinear inverse problems usually have no analytical solution and may be solved by Monte Carlo methods. Monte Carlo methods provide a set of samples, representative of the a posteriori distribution of the model parameters. We show how neural networks can be trained on these samples to give a continuous approximation to the inverse relation in a compact and computationally efficient form. Whereas traditional Monte Carlo methods require a full inversion for every new measurement, a trained neural network performs an inversion for a new data measurement instantaneously and provides similar probabilistic information about the solution. This illustrates that when repeated inversions are required, the cost of forming subsequent solutions can be reduced significantly by using neural networks. The samples we use for network training consist of noiseless synthetic Rayleigh and Love wave phase and group velocities and the corresponding 1-dimensional Earth models. The roles of input and output variables from the well-defined forward problem (i.e. computing phase velocities for a given Earth model using normal mode theory) are interchanged. We train a neural network on phase and/or group velocities as input vectors and the corresponding Moho depths as outputs. The trained networks approximate the probabilistic inverse mapping from phase and group velocities to the consistent (posterior) Moho depth distribution. The posterior distribution of the model parameters might be multi-modal. For this reason we go beyond the single Gaussian description and model the posterior density distribution of the model parameters as a mixture of Gaussians. Controlling the complexity of the neural network mapping is crucial. We decide to add Gaussian noise to the synthetic phase and group velocities where the standard deviation of the noise is given by the measurement error of the real phase and group velocities. Through the addition of the noise the network output is constrained to be less sensitive to small variations in the input variables. The trained networks are applied to real data. The real data set consists of fundamental mode Love and Rayleigh phase and group velocity curves. For each inversion we obtain the probability distribution of Moho depth at a certain location. From this distribution any desired statistic such as mean and variance can be computed. We construct global maps of maximum likelihood crustal thickness with error bars attached to it. The obtained results are compared with current knowledge of crustal structure as in Crust2.0. Generally our results are in good agreement with Crust2.0. However, we locate certain regions such as central Africa and the back arc of the Rocky Mountains where the Crust seems to be thinner than predicted by Crust2.0. In this application, characterized by repeated inversion of similar data, the neural network approach proves to be very efficient. In particular, the speed of the individual inversions and the possibility of modeling the whole posterior distribution of the model parameters make neural networks a promising tool in seismic tomography..


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Session 7: Ben Wyvis The Ben Wyvis range (translated from Gaelic as ‘the hill of terror’) lies 10km north of Strathpeffer. Its highest point, Glas Leathad Mor (‘big green hill’) is one of the most northerly of Scotland’s Munros (hills over 3,000ft). Ben Wyvis is a Designated Special Area of Conservation, owing to the presence of important habitats including alpine & boreal heaths, siliceous alpine & boreal grasslands and blanket bogs. Natural Analogues for Geological Storage of CO2 Jiemin Lu¹, Stuart Haszeldine¹, Gordon Macleod¹ and Mark Wilkinson¹ ¹ Institute of Earth Sciences Carbon capture and Storage in the subsurface has been identified as a potential technology to reduce CO2 emissions while permit the continued use of fossil fuels. Sequestrated CO2 would have to remain efficiently isolated from the atmosphere until natural buffering processes have sufficient time to reduce the CO2 concentration to its pre-industrial level. However, there is geological uncertainty concerning the possibility of long term leakage through a rock seal. To ensure a safe disposal it is necessary to understand and predict the CO2-induced reactions in cap rock. Natural CO2 fields provide direct natural analogues for CO2 geological storage, because these fields usually contain CO2 for geologic timescales. It is essential to examine natural CO2 sites in a quantitative way. In this study, samples from natural CO2-rich fields in the North Sea were examined in order to identify any change of mineralogy with CO2-related reactions; to quantify the mineral products and volumes of the reactions and the varying effect of CO2 on mudrock porosity and permeability; to constrain the reaction pathways and rates in the natural aquifer and mudrock seal. Quantitative analysis of mineralogy was performed on over 200 mudrock samples from Miller boreholes using X-ray powder diffraction. The results display vertical variations in mineralogy. Some of these changes may be related to CO2-induced reactions which tend to dissolve feldspar and precipitate carbonate and kaolinite. Scanning Electron Microscope (SEM) imaging of the samples revealed extensive secondary pores resulting from dissolution of quartz and feldspar by porefluid leaching. Late carbonate cements are recognized as probable products of the CO2-induced reactions.


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The Stability of Continuous Cover Forestry Axel Wellpott Institute of Atmospheric and Environmental Sciences Continuous Cover Forestry (CCF) is being increasingly practised in Britain. However, there are concerns whether this type of forest management is feasible due to the severe wind climate of Britain. Most of the studies that deal with this question are based on data from continental Europe and may not be applicable to British forestry. All the advantages that CCF has over clear felling would become much less valuable if it turned out that there was increased risk of wind damage so that economic penalties exceeded the benefits. ForestGALES is a mechanistic model that calculates the wind loading on trees and predicts the risk of windthrow for forest stands in Britain. The equations that are used in the model were estimated from field campaigns in even aged forests or similar forests simulated in the wind tunnel. The change in forest policy in Britain necessitates modifications to the model so that it is able to calculate the risk for stands that have a mixed species and age structure. To help achieve this goal we set up a field campaign in a stand in North Wales which contains a lot of natural regeneration and can therefore be regarded as a stand in transformation from even aged forestry to CCF. A 30m mast with 8 cup anemometers, 2 wind vanes and a sonic anemometer mounted on it was erected in the stand to measure wind profiles with a high vertical spatial resolution. Simultaneously, strain gauges attached to nine trees within the stand measured the forces the trees experienced with a time resolution of 4Hz.


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Exploration of the Barmer Basin, Rajasthan, India, 2005-2006 - A Personal Perspective David Bailey Cairn Energy Plc Cairn Energy Plc is Europe’s largest independent oil & gas exploration company whose head office is based in Edinburgh. Cairn's present operations are based in SE Asia in India, Nepal and Bangladesh. Current exploration is primarily focused in NW India, in the Barmer Basin, Rajasthan. To date 17 fields have been discovered in the Barmer Basin, with exploration ongoing. The most significant discovery is the Mangala Field, a billion barrel oil accumulation discovered in January 2004. Appraisal of the Mangala Field is continuing to optimize the field and maximize recovery when production commences in 2007. The hydrocarbon exploration process begins with the acquisition and interpretation of new 2D & 3D seismic data covering unexplored parts of the basin. Potential prospects are then identified, assessed, risked and in-place volumes estimated, to individually evaluate the potential of each prospect. Once drilled, a detailed assessment of the well can then be made of the results using well logging techniques and petrophysical analysis. This presentation will focus on personal experience of the exploration process over the nine month period I’ve been with Cairn, during which time over 20 exploration wells have been drilled.


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Agent-based modelling in agricultural policy Conrad Rider Institute of Geography The agricultural industry in Europe and the United Kingdom is a vital player in the economy and is a lively hood for many of its participants. In a bid to support and protect the industry, the European government has developed the Common Agricultural Policy (CAP). This protects farmers and markets and ensures the quality of agricultural goods through subsidies, trade taxes and regulation. The European Union's (EU) constituent countries have a great deal of variance in land, economic and technological resources, climate, culture and attitudes. This makes the construction of a single agricultural policy to manage the entire EU a difficult and complicated process. The problem of heterogeneity between areas not only occurs at the national level, but occurs at the regional level and even the farm level. This hinders the job of national governments implementing more specialised policies to deal with the specific needs of a nation. So what can ever more powerful computer technology offer? First appearing over 20 years ago with Hogweg and Hesper's work on Bee colonies and Craig Reynolds pioneering work on flocking simulations, agent-based simulation has now established its place in the ecological modelling community. During this time it has been applied to many scientific problems in ecology, ranging from the obvious applications in population dynamics, to the complex issues in policy design. During this period the technique has been developed and matured, but because of its nature there are still a significant number of barriers in our understanding. The intrinsic complexity within an agent-based simulation has hindered these models in their ability to provide concrete quantitative results and makes them somewhat difficult to verify. So how can this technique break out of research field to provide concrete results, usable by national and European policy developers?


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Seismic Interferometry: From the lab to the field David F Halliday Institute of Earth Sciences The theory of Seismic Interferometry allows unknown Green’s functions to be computed between receiver positions, without having an active source at either position. The unknown data is found by a simple process of cross-correlation and summation of data recorded at these positions, from external sources on a surrounding boundary. By increasing the number of receiver positions, the number of possible Green’s functions available increases without any need to increase the number of sources. The only increase is in the cost of storing the data. The theory has been shown to work in laboratory experiments and computer models, where the user has complete control over the properties of the media in question. However, in the field, with real geological situations, this control is not available. To implement the theory in the field a simple experiment has been carried out using the School of GeoScience’s seismic acquisition equipment. Results show that in some cases the calculated Green’s functions can be compared with signals recorded between the two positions of interest. However, the overall results are not yet consistent. Reasons for these discrepancies and some possible solutions are discussed.

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