Gjesteforelesning - Nigel Hughes
By invitation of the Natural History Museum, Professor Nigel Hughes from Department of Earth Sciences University of California Riverside will give the lecture "Twenty Years on the Margins: paleontological and stratigraphic constraints on Himalayan structure and uplift."
Professor Hughes has degrees from the universities of Durham, England (BSc) and Bristol (PhD) with additional awards from the University of West Bengal, India. He has held postdoctoral fellowships at the University of Brisbane, Australia and the Smithsonian Institution, U.S.A. and was curator of invertebrate palaeontology at the Cincinnati Museum U.S.A. before taking up his position at the University of California, Riverside where he became full professor in 2003. His research interests cover a wide field but he is best known for his work on the early evolution of trilobites, their genetic coding, aspects of the Cambrian radiation and the role of fossils in solving the early Palaeozoic history of Gondwanaland. His talk will discuss his work in the Himalayas and will be illustrated with spectacular photographs from field work at over 5000 m altitude.
The Himalaya offer spectacular insights into the nature of continent-continent collision and have provided a fertile ground for developing major ideas in tectonic geology. Such insights are, however, limited by our understanding of the basic geology of the Himalayan system. In recent years spurious reports of fossils and surprisingly large gaps in our basic knowledge of Himalayan stratigraphy have limited the role that stratigraphic geology has played in constraining models of Himalayan evolution. Over the last 20 years our group has taken a special interest in the Cambrian geology of the Himalaya because of all Palaeozoic systems the Cambrian has the widest geographical occurrence in the Himalaya. By focusing on rocks whose depositional age can be accurately constrained by fossils, we have been able to test recent tectonic models both for the pre-collisional structure of the Himalaya, and its more recent uplift and erosional history. I will argue that insights from the Cambrian System allow us to correlate along and across the Himalayan margin and to refute the idea that the northern parts of the Himalayan system are a distinct terrane. I will also suggest that understanding of this Cambrian history allows us to reconcile a discrepancy in the estimate of timing of uplift of the Lesser Himalaya during the Miocene.