DECODING THE DYNAMICS OF THE HIMALAYA: REFLECTIONS ON THE REMARKABLE CAREER CONTRIBUTIONS OF MICAH JESSUP (Invited Presentation)

In a more than twenty-year career, Prof. Micah Jessup and his students have made numerous discoveries in the Andes, southwestern USA, and the Himalaya that have advanced our understanding of the fundamental architecture and development of orogenic systems at the process level. This presentation will highlight and reflect on the significance of three (of the many) breakthroughs that Micah and his team made while studying the length and breadth of the Himalaya, including: 1) resolving the kinematics of the South Tibetan Detachment system and shedding light on the mechanisms by which the metamorphic core of the Himalaya was exhumed; 2) defining the causes and consequences of the mid-Miocene switch from orogen-perpendicular contraction to orogen-parallel extension and developing a model for the topographic history and distribution of strain on the southern margin of the Tibetan Plateau, and; 3) revealing the thermokinematic development of North Himalayan gneiss domes, and providing insight into the processes that localize strain in the mid-crust. In each case, Micah’s work was characterized by carefully ground-truthed field observations and attention to detail that allowed him to see patterns in the rock record missed by others. In support of these field-based studies, Micah employed a range of cutting-edge microstructural, petrologic, and geo/thermochronologic techniques that together offered him a clarity of insight into how the deep crust responds to continental collision, as well as the ways in which deep-earth and near-surface processes are connected, and together shape the geomorphological expression of the Himalaya. In exploring these contributions, I will highlight the numerous examples where Micah’s research findings have been and continue to be influential on our current understanding of how the Himalayan orogen developed through the Cenozoic, as well as some of the foundational questions raised by Micah’s research that remain unanswered.