Mongolia occupies a key position for unraveling the complex geologic history of central Asia, which formed through the accretion of "exotic" crustal fragments in the late Paleozoic-early Mesozoic. Students involved in this Keck Geology Consortium research project are contributing important new geologic data about the Gobi-Altai terrane in Mongolia — its sedimentary history, evolution of its invertebrate communities, and paleogeographic setting.
Field work in July-August 2009 allowed us to investigate the paleontology, stratigraphy, and sedimentology of Ordovician-Devonian deposits exposed near Shine Jinst in the Gobi-Altai terrane of southern Mongolia. Joint work with a Mongolian colleague and students from Mongolian Technical University entailed detailed field mapping and systematic sampling of sedimentary rocks (primarily limestone but also interbedded clastic and volcanic units) and fossils from measured and photographed stratigraphic sections. Compilation of sedimentary (petrologic and petrographic), chemo-stratigraphic, magnetic susceptibility, and paleontologic data will form a comprehensive database for determining the environmental setting, paleoecology, and faunal affinities of the biotas. Similarities in rock and fossil compositions, particularly chemo-stratigraphic profiles and suites of fossils with distinctive provincial affinities, will be used to establish paleogeographic connections with adjoining terranes (or continental areas) and to determine the evolutionary history of Mongolian biotas in the early Paleozoic.
During the 2009-2010 academic year, students completed research projects and prepared their results for presentation at the annual Keck Geology Symposium in Houston, Texas, in April 2010.
Bodonguud Chuluun Minjin (Mongolian University of Science and Technology) U.S. Director:
Constance M. Soja (Colgate University)
Project Faculty: Paul Myrow (Colorado College); Jeff Over (SUNY-Geneseo) U.S. Students:
Timothy Gibson (Colorado College); Madelyn Mette (Macalester College); Sara Oser (University of Cincinnati); Adam Pellegrini (Colgate University); Jennifer Peteya (Mt. Union College); Nadine Reitman (Vassar College); Nicholas Sullivan (SUNY-Geneseo); and Zoe Vulgaropulos (Oberlin College) Mongolian Students:
Uyanga Bold; Bilguun Dalaibaatar; Badral Khurelbaatar; and Munkh-Od Purevtseren (Mongolian University of Science and Technology)
This map shows the hypothesis to be tested about possible paleogeographic placement of Mongolia (terranes are clustered together) near the eastern extent of the Uralian Seaway in the Silurian. Stars show occurrence of Upper Silurian deposits used to constrain paleogeography of the Alexander terrane (AT) along the Uralian Seaway in proximity to (2) Farewell terrane in sw Alaska, (3) Pay-Khoy, (4) Ural Mountains, and (5) Salair. Does the Gobi-Altai terrane share similar sedimentary sequences and biotas with any of these areas? Map is modified from Silurian basemap of Scotese (2001) and from paleogeographic models in Sengšr et al. (1993), Lamb and Badarch (1997), Landing and Johnson (1998), Scotese (2001), Cocks and Torsvik (2002), Yolkin et al. (2003), Soja et al. (2000), and Torsvik and Cocks (2004).
it was an epic journey involving four days of travel in two rugged 11-person Russian vans and an army truck, which transported fuel, water, food, a generator, refrigerator, cooktop stove, and other supplies. We departed from Mongolia's capital, Ulaanbaatar, and reached the Shine Jinst region of the Gobi Desert more than 900 km (600 miles) later.
our Mongolian colleagues were well prepared for camping in the Gobi Desert. A local couple guided our efforts in setting up a ger (traditional felt tent - transported from Ulaanbaatar for use as our kitchen and office area), which took about an hour.
We camped in tents in a mountainous, sparsely vegetated, and largely uninhabited area atop Carboniferous shales. Mongolian traditions:
we were fortunate to be invited to attend a traditional Mongolian wedding set in an isolated ger in the Gobi Desert, thanks to our expedition leader, Minjin.
We also observed the preparation of traditional Mongolian feasts, including the slaughter, cleansing, dismemberment, and rendering of a sheep (all parts are consumed!), and enjoyed tasting other local delicacies, including airag (fermented mare's milk) and sheep- or goat-milk cheese. Each of us also got a turn riding a camel! (Bottom Left) Our camp cook Tseteegee Buyndelger also prepared meals for us during our trip. On this morning, she whipped up a sweet breakfast treat of fritters that could be dipped in either honey or jam. (Bottom Right)
Rock samples: we collected and shipped back to the U.S. more than 500 kg – the equivalent of about 1,100 pounds – of rock, which kept everyone on the team of the Keck Mongolia 2009 research trip busy for months after returning from the trip.
Thanks to the resiliency and dedication of all participants, we have shared memories, the bond of friendship, and many outstanding geologic questions to guide our research activities over the coming year. We thank the Keck Geology Consortium, especially Director Andy deWet, and Colgate University for research funds. Special appreciation is extended to Minjin for guiding our research at localities he has been studying for 30 years. Thanks are also due to each student's research advisor at his/her home institution for the invaluable help and counsel they will provide this year.
- Cocks, L.R.M., and Torsvik, T.H. 2002. Earth geography from 500 to 400 million years ago: a faunal and palaeomagnetic review. Journal of the Geological Sciences, 159:631-644.
- Lamb, M.A., and Badarch, G. 1997. Paleozoic sedimentary basins and volcanic-arc systems of southern Mongolia: New stratigraphic and sedimentologic constraints. International Geology Review, 39:542-576.
- Landing, E., and Johnson, M. (eds.) 1998. Silurian cycles: Linkages of dynamic stratigraphy with atmospheric, oceanic, and tectonic changes. New York State Museum Bulletin 491.
- Scotese, C.R. 2001. Digital paleogeographic map archive on CD-ROM. PALEOMAP Project. University of Texas (Arlington). http://www.scotese.com (PALEOMAP website).
- Sengšr, A.M.C., Natal'in, B.A., and Burtman, V.S. 1993. Evolution of the Altaid tectonic collage and Palaeozoic crustal growth in Eurasia. Nature, 364:299-307.
- Soja, C.M., White, B., Antoshkina, A., Joyce, S.,* Mayhew, L.,* Flynn, B.,* and Gleason, A.* 2000. Development and decline of a Silurian stromatolite reef complex, Glacier Bay National Park, Alaska. Palaios, 15:273-292. (*=student co-author)
- Torsvik, T.H., and Cocks, L.R.M. 2004. Earth geography from 400 to 250 Ma: A palaeomagnetic, faunal and facies review. Journal of the Geological Society, London, 161:555-572.
- Yolkin, E.A., Sennikov, N.V., Bakharev, N.K., Izokh, N.G., and Klets, A.G. 2003. Silurian paleogeography along the southwest margin of the Siberian continent: Altai-Sayan folded area. In Landing, E., and Johnson, M.E. (eds.). Silurian lands and seas: Paleogeography outside of Laurentia. New York State Museum Bulletin 493:299-322.