Ladakh exhibition gallery
From 1977 to 1983, Aymon Baud (Geological Museum) participated in excursions, field campaigns and research in Ladakh and Zanskar (North India). Initiator of the research group on the Himalayas of the Museum and the University of Lausanne, he organized with Professors A. Escher, H. Masson and A. Steck the first geo-traverse of Eastern Zanskar, Hemis-Padum, in 1979. In 1981, he organized an expedition with Prof. G. Masde (Grenoble) and Dr. E. Garzanti (Milan) to make detailed stratigraphic sections and tectonic observations in central Zanskar, N and E of the Spongtang ophiolite klippe. In 1983, invited by Prof. M. Gaetani (Milan), he participated in a SE-NW geotraverse from Darcha (l.ahul) to Thongde (Zanskar) via Sarchu, Phirtse-La and Phugtal.
As western Tibet was only opened to foreigners in 1985, he was the first western geologist to enter the Kaila region after A. Gansser in 1936 and to cross the Tibetan plateau from Toling on the Sutlej valley to Yarkand, north of the Kun-Lun range.
For the collection of samples on the classic sections of the Permian-Triassic boundary, he participated in 1987 in an IGCP field meeting at Sall Ranges (Pakistan) followed by a field campaign in Kashmir (India) with Prof. G.Gaetani, J. Marcoux and E.T. Tozer.
In October 1988, he organized with Professors H. Masson, G. Stämpfli and A. Steck the fourth Himalaya-Karakoram-Tibet workshop in Lausanne. Steck the fourth Himalaya-Karakoram-Tibet workshop in Lausanne and was the editor of the conference proceedings published in Eclogae Geol. Helv. vol. 82.2 (1989).
The main results obtained in collaboration with the above mentioned teams can be summarized as follows:
- The discovery and definition of a large-scale vergent nappe structure in the Zanskars sedimentary belt (Tethys Himalaya). Despite strong opposition and controversy about the nappe theory by native-minded geologists, the nappe structure has recently been confirmed by detailed fieldwork and mapping.
- A geological profile through East Zanskar from Hemis to Padum.
- Detailed stratigraphic sections of the late Cretaceous and early Tertiary sediments of central Zanskar with geodynamic interpretation of the sedimentary record of the northward flight to India.
- New observations in the Kailas region and along the Sutlej-Yarkand geotraverse.
- Permian-Triassic isotope stratigraphy in the Salt Ranges and Kashmir.
- A new geodynamic interpretation and chronology of Late Paleozoic rifting.
- Baud, A. (1985): Geological observations on a geotraverse from the Sutlej to the Yarkand River Tibet). - In 2nd Himalayan Worshop, Abstracts . Leicester
- Baud, A. (1986): The main structural elements of W Tibet and their correlations. - Tn CRPG, N. (Ed.),3rd Himalaya-Karakoram Worshop, Abstracts, p. I, Nancy:
- Baud, A. (1989a): Colloque Himalaya-Karakoram-Tibet. Avant-propos. - In Baud, A. (Ed.), Colloque Himalaya-Karakoram-Tibet, Lausanne, 1988. Eclogae. Geol. Helv. 82/2, p. 583-584.
- Baud, A. (1989b): Autochthony in slick country: a response AG. Fuchs. - Eclogae. Geol. Helv. 82 /2, p. 693-697.
- Baud, A. (1989c): The western end of the Tibetan plateau. - In Sengor, A.M.C. (Eds.), Tectonic evolution of the Tcthyan region. pp. 505-506. Dordrecht Kluwer Acad. Puhlishers.
- Baud, A. (1992): Nappe and Thrust tectonics in Zanskar area (NW Himalaya): review of the so-caled " autochtony of the Tethys-Tibetan zone. - In Shina, A.K. (Eds.), Himalayan orogen and global tectonics, pp. 45-48. Kew Delhi: Oxford & IBH.
- Baud, A., Am, R., Bugnon, P., Crisincl, A., Dolivo, E., Escher, A., Hammerschlag, J.G., Marthaler, M., Masson, H., Steck, A. & Tieche, J.G. (1982): The Gondwana-peri-Gondwana contact in eastern Zanskar (Ladakh-Himalaya). - Bull. Soc. geol. Fr, 24 (2), pp. 341-361.
- Baud, A.. Am. R., Bugnon, P., Crisincl, A., Dolivo, E., Escher, A., Hammerschlag, J.G., Marthaler, M., Masson, H., Steck, A. & Tieche, J.G. (1983): Geological observations in the Eastern Zanskar area, Ladakh (Himalaya). - In Gupta, V.J. (Eds.), Contribution to Himalayan Geology, pp. 130-142,. Dehli: Hindustan Publ.
- Baud, A., Gaetani, M., Gar1.anti, E., Fois, E., Nicora, A. & Tintori, A. (1982): Are the Tibetan Himalayan series allochthonous: new observations in eastern Zanskar (North India). - In Soc. Geol. France. (Ed.), IXe RAST, resume, p. 33. Paris.
- Baud, A., Gaetani, M., Garzanti, E., Pois, E., Nicora, A. & Tintori, A. (1984): Geological observations in South-Eastern Zanskar and adjacent Lahul area (northwestern Himalaya). Eclogae. Geol. Helv. 77, pp. 171-197.
- Baud, A., Garzanti. E. & Mascle, G. (1984): The structure of Zanskar (Ladakh, NW Himalaya). results from the superposition of carbonate nappes from the Gondwanian margin of the Tethys. In Soc. Geol. France (Ed): Xe RAST, resume. Bordeaux.
- Baud. A., Garzanti. E. & Masclc, G. (1985): Latest marine sediments (Early Paleogene), geological events and nappe structure in the central Zanskar area (N\V Himalaya). - In 2nd Himalayan Worshop. Abstracts . Leicester:
- Baud, A., Garzanti, E. & Mascle, G. (1986): Evolution des facies durant le Crétacé superieur au Zanskar, NW Himalaya. - In CRPG, N. (Ed.), 3rd Himalaya-Karakoram Workshop, Abstracts, p. 2, Nancy:
- Baud, A. & Magaritz, M.(1988): Carbon Isotope Profile in the Permian Triassic of the Central Tethys: The Kashmir Sections (India). Berichte der Geologisch. Bundesanst. band 15, p 2, Wien.
- Baud, A. & MagariLz, M., 1989. Intercorrelations between Isotopic and Biologic Time Scales at Permian-Triassic Boundary: Transcaucasus and Kashmir Sections. Abstracts, volume 1 of 3, p. 102, 28th International Geological Congress, Washington, D.C. USA, July 9-19, 1989.
- Baud, A., Magaritz, M., & Bolser, W.T., 1989. Permian-Triassic of the Tethys: Carbon isotope studies. Geologische Rundschau 7812, pp. 649-677, Stullgarl.
- Baud, A., Marcoux, J., & Stamplli, G., 1989. Late Permian-Early Triassic Tethyan Margin of India: Evolution from Rifting to Drifting (Salt-Range, Kashmir, Zanskar Traverse). Abstracts, volume 1 of 3, p. 103, 28th International Geological Congress, Washington, D.C. USA, July 9-19, 1989.
- Burg, J.-P., Bonneville, A., Baud, A., Girardeau, I. & Marcoux, J. (1991 ): First results on the Broadcast Ophiolitic in a Collision Bell: the Jungbuwa Thrust Sheet, North Tibet. - In AGU (Ed.), AGU annual meeting, abstract hook.
- Frank, W., Baud, A., Honegger, K., Trommsdorff, V.(1987): Comparative studies across the northwest Himalayas. In Schaer & Rodgers (Ed.): The Anatomy of Mountain Ranges. p. 261-275.
- Garzanti, E., Baud, A. & Mascle, G. (1987): Sedimentary record of the northward flight of India and its collision with Eurasia (Ladakh Himalaya, India). - Geodinamica Acta Paris, 1 (4-5), pp. 297-312.
- Stampfli, G., Marcoux, J. & Baud, A. (1991): Tethyan margins in space and time. - Palaeogeogr, Palacoclimatol, Palaeoecol, 87, pp. 373-409.
Since 1979, geologists from the University of Lausanne have been working in the Himalayas, in particular over a distance of about 200 km between the Indus Valley in the north and the Rohtang Pass in the south. The study was conducted under the active supervision of Professors H. Masson and A. Steck, and involved four doctoral theses and several specialist field sessions.
The entire cross-section has been mapped at 1:50,000 scale and numerous lithostratigraphic sections have been established for the Indus Molasse, the Mixed Zone, the Distal Lamayuru Unit, the Tibetan Zone and the High Himalayan Crystalline. Detailed stratigraphic studies have been carried out on the Indus molasse, Paleozoic and Lower Triassic of the Tibetan zone.
- The good knowledge of this cross-section allowed the Lausanne group to propose coherent models for the pre-collisional history of the northern margin of India and the tectonic-metamorphic evolution of the region during the Tertiary. The main points are:
New interpretations of the Lower Cambrian depositional environment.
- Evidence for extensional events during the so-called Pan-African Orogeny during the Ordo-Silurian.
- The Late Paleozoic pre-rift history has been divided into three tectono-magmatic levels ranging from the Lower Carboniferous to the Upper Permian.
- A new model for the tectonic and metamorphic evolution of the suture zone, the Tibetan zone, and the crystalline nappes has been proposed.Detailed structural studies highlight the presence of early NE vergent defoliation in the southern crystalline domain.
- Metamorphic constraints are based on petrography, electron microprobe analyses of illite crystallinity and radiometric data (K/Ar, Ar/Ar).
- A discontinuous reverse metamorphic zonation in the Tibetan zone was revealed by the illite crystallinity method and radiometry.
- Detailed structural analysis has revealed late extensional structures in the Tibetan zone.
This work has been summarized in four doctoral theses (Stutz 1988; Spring 1992; Vannay 1993; Talon (in progress)}, and in publications. The members of the Lausanne group have given several lectures and poster presentations at the Himalaya - Karakorum - Tibet workshops (organizers of the 1988 session in Lausanne), in Grenoble (1990) and in China (Kashgar 1992).
Bucher, H. & Steck, A. (1987): Stratigraphy and tectonics in the Indus basin: the Martselang - Gongmaru la section (Ladakh) - Terra Cognita, 7, 112.
Masson, H., Steck, A., Bucher, H., Spring, L., Stutz, E. & Vannay, J.C. (1990): Geology of the Eastern Ladakh Nappes, Rohtang La - Leh I and II.- V Himalaya-Tibet- Karakorum Workshop, Milano, Abstract vol. 34-35.
Spring, L. ( 1992): Gondwanan and Himalayan structures in the Tibetan area of the Upper Lahul - Eastern Zankar (Indian Himalaya) - Thesis University of Lausanne.
Spring, L. & Crespo - Blanc, A. (1992): Nappe tectonics, extension and metamorphic evolution in the Indian Tethys Himalaya (SE Zanskar-NW Lahul) - Tectonics, 11/5, 978-989.
Spring. L., Bussy, F., Vannay, J.C., Huon, S. & Cosca, M. (in press): Permo-Carboniferous granitic magmatism of alkaline affinity in the Indian High Himalaya (Upper Lahul - SE Zanskar): geochemical characterization and geotectonic implications.- Geol. Soc. London Spec. Publ.
Spring, L., Masson, H., Stutz, E., m, Ph., Marchant, R. & Steck, A. (in press): Inverse metamorphic zonation in very low - grade Tibetan Zone series of SE Zanskar and its tectonic consequences (NW India, Himalaya) - Schweiz. Min. Petr. Mitt.
Steck, A., Spring, L., Vannay, J.C. Masson, H. Bucher, H., Marchant, R., Stutz, E. & Tiche, J.C. (in press): Geological cross section through the Northwestern Himalayas in eastern Ladakh and Lahul - Eclogae Geol. Helv.
Steck, A., Spring, L., Vannay, J.C. Masson, H., Bueher, H., Marchant, R., Stutz, E. & Tieche, J.C. (in press): The tectonic evolution of the Northwestern Himalaya in eastern Ladakh and Lahul. Geol. soc. London Spec. publ.
Stutz, E. (1988): Geology of the Nyimaling Range in the Ladakh-Rupshu confines (NW Himalaya, India): paleoglographic and tectonic evolution of a segment of the North Indian margin.- Mem. Geol. Lausanne, 3, 149 pp.
Stutz, E. & Steck, A. (I 986): The western termination of the Tso Morari crystalline (Upper Himalaya; Meridional Ladakh, India): subdivision and nappe tectonics.- Eclogae Geo. Helv, 79/2, 253-269.
Stutz, E.& Thoeni, M. (1987): The Lower Paleozoic Nyimaling granite in the Indian Himalaya (Ladakh): new Rb/Sr data versus zircon typology.- Geol. Rund, 76/2, 307-315.$
Talon, C (1990): Peridotite and associated basalts of the Markha valley (Ladakh, NW Himalaya).- V Himalaya-Tibet-Karakorum Workshop, Milano, Poster.
Vannay, J-C. & Spring, L. (in press): Continental basalts within the Tethyan Himalaya of Lahul-Spiti (NW India): markers of the Permo-Mesozoic Tethys rifting.- Geol. soc. London Spec. publ.
Vannay, J.C. (1990): La structure du haut Himalaya indien au Lahul.- 13mc reunion des sciences de la terre, Grenoble 1990, ed. by Soc. Geol. de France, Paris, 123.