Research for my Ph.D. centered around the evolution of the India-Asia suture zone after India-Asia collision, around 60 million years ago. This multi-disciplinary project was funded by the Continental Dynamics program at NSF and involved over 35 professors, postdocs, graduate students, and undergraduates at eight universities worldwide. Fieldwork was conducted during the summers of 2011, 2012, 2013, and 2014 (I participated in all but the 2014 season). My work on this project focused on two groups of rocks exposed within the India-Asia suture zone: the Liuqu Conglomerate and the Kailas Formation.
The Liuqu Conglomerate was deposited in north-flowing alluvial and fluvial fans. The unit is composed of conglomerates interbedded with mature paleosols. Previous age estimates for the Liuqu Conglomerate range between Paleocene and Miocene. My work has refined this age to ca. 20 Ma based on a synthesis of detrital zircon U-Pb, U-Th/He, and fission track analyses; biotite 40Ar/39Ar data; soil carbonate stable isotope data; regional structural constraints; and reanalysis of palynologic and plant fossil data. These results as well as a thorough study of the Liuqu Conglomerate’s sediment provenance and basin setting are published in the journal Lithosphere. Stable isotope and major element analyses of Liuqu paleosols have enabled a robust reconstruction of the paleoclimate conditions within the India-Asia suture zone at ca. 20 Ma; this work is published in journal Geology.
The Kailas Formation is exposed semi-continuously over ~1300 km along the India-Asia suture zone. It is made up of alluvial, fluvial, and lacustrine rocks and was deposited in an extensional basin. My work studied the Kailas Formation exposed within the central India-Asia suture zone and established, among other things, that these rocks are younger to the east. The spatial-temporal pattern of Kailas basin sedimentation is nearly identical to, although several million years preceding, the eruption of adakitic and ultrapotassic rocks in the Lhasa terrane to the north; these rocks have been interpreted to be the result of the breakoff of the subducted Indian continental slab. Combined with the results of geophysical studies of southern Tibet, these data suggest that formation of the Kailas basin was driven by Indian slab shearing that began in western Tibet and migrated eastwards. Results of this study are published in the journal Geosphere.
Subsequent publications related to this project include a synthesis of basin evolution in the India-Asia suture zone and a study on the challenges of applying paleoaltimeters in southern Tibet.