These zircon data provide further evidence for charnockiticplutonic activity and granulite -facies metamorphism 900-1100million years ago in an east-west trending belt exposed inwestern Enderby Land, Mac. Robertson Land, and the IngridChristensen Coast.

This research was supported by National Science Founda-tion grants DPP 75-17390 and DPP 76-80957 to the University ofCalifornia, Los Angeles. Grew thanks members of the 18thand 19th Soviet Antarctic Expeditions for their logistic supportand cooperation.

References

Fedorov, L. V., and Grikurova, D. V. 1980. Sillimanitsoderzhashchiyeredkozemelnyye pegmatity kholmov Reynbolt (VostochnayaAntarktida) [Rare earth pegmatites containing sillimanite of Rein-

bolt Hills (East Antarctica)]. Trudy Sovetskoy Antarkticheskoy Ekspe-ditsii, 70, 107-111.

Grew, E. S. 1978. Precambrian basement at Molodezhnaya Station.Geological Society of America Bulletin, 89(6), 801-813.

Grew, E. S. 1980. Sillimanite and ilmenite from high-grade metamor-phic rocks of Antarctica and other areas. Journal of Petrology, 21(1),39-68.

Grew, E. S., and Manton, W. I. 1977. Age of zircons from pegmatiteat Reinbolt Hills, Ingrid Christensen Coast, Antarctica (70°30'S.,72°30'E.). American Geophysical Union Transactions, 58, 1250.(Abstract)

Ravich, M. G., Solovyev, D. S., and Fedorov, L. V. 1978. Geologiches-koye stroyeniye Zexli Mak-Robertsona (Vostochnaya Antarktida) [Geo-logical structure of Mac. Robertson Land (East Antarctica)]. Lenin-grad: Gidrometeoizdat.

Tingey, R. J . In press. The geological evolution of the Prince CharlesMountains—An antarctic Archaean cratonic block. In C. Craddock(Ed.), Antarctic geoscience. Madison: University of Wisconsin Press.

Petroleum resources of Antarctica*

JOHN C. BEHRENDT

U.S. Geological SurveyDenver, Colorado 80225

There are no known petroleum resources in Antarctica, andinformation on which to base reliable estimates of undiscov-ered resources is lacking. Given the hostile antarctic environ-ment, only giant fields (approximately 70 million tons, or 0.5billion barrels), or more probably supergiant fields (approxi-mately 700 million tons, or 5 billion barrels), could reasonablybe considered economical in the next few decades. Consider-ing the locations of known giant oil fields in the world, Ant-arctica does not appear a very good prospect. The location ofAntarctica in the Gondwanaland reconstruction suggests thatWest Antarctica is the area most likely to contain petroleumresources. Probably only the continental margins (possibly

*This paper will be published in Mineral Resource Potential of Antarcticaby I . Splettstoesser (University of Texas Press).

including ice-shelf areas) bordering the Ross, Amundsen, Bel-lingshausen, and Weddell Seas will be exploitable with presentor future technology because of the several-kilometers-thickmoving grounded ice sheet covering the rest of Antarctica.

Geophysical data are sparse but do suggest the presence ofseveral kilometers of unmetamorphosed sedimentary rock(possibly Cretaceous and Tertiary age) beneath the Ross andWeddell continental shelves. There is no information on theAmundsen and Bellingshausen continental shelves. SeveralDeep Sea Drilling Project (osDr') holes beneath the Ross con-tinental shelf have shown the presence of Tertiary marine andnonmarine sedimentary rocks as old as Oligocene in age over-lying early Paleozoic basement. Shows of gas in the DSDP holes,although provocative, cannot be considered evidence of anyhydrocarbon resources. Technology to exploit possible petro-leum resources in Antarctica is developing faster than thescientific studies directed at resource assessment and environ-mental hazards, and faster than the international legal processof establishing a mineral resources regime to determinewhether, or under what circumstances, industrial explorationand exploitation should be permitted. As future geophysicaland geologic studies outline possible prospective areas, sci-entific studies are needed of hazards associated with geologic,meteorologic, and oceanographic conditions, as well as eco-systems that might be affected adversely.

Tectonic studies in the Scotia Arcregion and West Antarctica

IAN W. D. DALZIEL

Lamont-Doherty Geological Observatory of Columbia UniversityPalisades, New York 10964

My students and I were involved in two major field studiesduring the 1980-81 austral summer. The first involved a con-tinuation of work in the southernmost part of the Andean

Cordillera undertaken by scientists from Lamont-Doherty overthe past 12 years. The second involved a new venture in WestAntarctica undertaken in cooperation with scientists of theBritish Antarctic Survey (see Doake and Crabtree, AntarcticJournal, this issue).

With the absence of RIVHero as a result of her major overhaul,the South American work was limited to the foothills of theAndean Cordillera. Here Terry Wilson completed a detailedstructural traverse from the outcrop of the Upper JurassicTobifera Formation through the folded and thrusted Lowerand Upper Cretaceous strata of the foreland fold and thrustbelt to the outcrop of the Tertiary. This traverse was located inthe district of Ultima Esperanza near the spectacular Miocenegranitic pluton of Cerro Paine. The structures in the area stud-

1981 REvIEw 7