I just returned from a very interesting and pleasant field trip in Himachal Pradesh (India) to examine the major elements of the frontal portion of the NW Himalaya. The trip was lead by Dr. Rasmus Thiede of the University of Potsdam (UP). This was my third trip to the Himalayas (the first in 2001 to the Sutlej and Spiti Rivers with UP colleagues including Rasmus and Bodo Bookhagen when they were starting their Ph.D.s under the supervision of Professor Manfred Strecker; the second was in 2010 with Dr. Wendy Bohon in the Ladakh region to contribute to her work along the Karakoram Fault in the Pangong Range area). We joined two UP students (Katharina Kretzschmar and Markus Nennewitz) who had been working in the area for two weeks already, focusing on developing a structural profile across the principal faults of the NW Himalaya in the region. I overlapped for a day with Dr. Saptarshi Dey who worked on his Ph.D. with Rasmus in the Kangra reentrant (see Dey, et al., 2016a,b). And, it was a pleasure to meet Professor Vikrant Jain from IIT Gandhinagar and his Ph.D. students. I did not (yet) get their last names but they were Ramindran, Sonam, and Pritha. Tashi Gyatseo is a long-time guide and friend of Rasmus who was chief of logistics for the trip. It was fun to meet everyone and to discuss the geology and geomorphology as well as learn a bit more of eachother's cultures.
Along with strengthening the collaborations among the groups, there were a couple of scientific targets of the trip. They build to a large degree from the Ph.D. work of Saptarshi Dey and focus on:
- The role of climate modulation of the sediment supply and transport capacity along the major river systems and the development (and removal) of fluvial fills and terraces.
- The activity of the major faults of the system, including the Himalayan Frontal Thrust and out of sequence faulting (activity higher in the tectonic wedge) possibly influenced by load variation from changes in sediment storage in the orogenic wedge.
GaiaGPS app for my mapping. It seems ok but I might look for a more geologically oriented app for the next trip.
Dey, S., Thiede, R., Schildgen, T., Wittmann, H., Bookhagen, B., Scherler, D., and Strecker, M. Holocene internal shortening within northwest Sub-Himalaya: Out-of-sequence faulting of the Jwalamukhi Thrust, India: Tectonics, 2016a.
Dey, S., Thiede, R. C., Schildgen, T. F., Wittmann, H., Bookhagen, B., Scherler, D., … Strecker, M. R. (2016b). Climate-driven sediment aggradation and incision since the late Pleistocene in the NW Himalaya, India. Earth and Planetary Science Letters, 449, 321–331. https://doi.org/10.1016/j.epsl.2016.05.050
Gavillot, Y., Meigs, A., Yule, D., Heermance, R., Rittenour, T., Madugo, C., & Malik, M. (2016). Shortening rate and Holocene surface rupture on the Riasi fault system in the Kashmir Himalaya: Active thrusting within the Northwest Himalayan orogenic wedge. Bulletin of the Geological Society of America, 128(7), 1070–1094. https://doi.org/10.1130/B31281.1