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An example of science aided by cyberinfrastructure - Geodynamics of the Himalaya Chris Andronicos Institute for the Study of the Continents, Cornell University and Aaron A. Velasco, Jose M. Hurtado Department of Geological Sciences University of Texas at El Paso Can you do science with what is already out there? The Internet provides access to a vast amount of data in various subjects but… The data is usually not peer reviewed Some available information is of dubious nature Data is often available in formats which are difficult to utilize for the problem of interest Data may be out of date Datasets and Programs Used Harvard Centroid Moment Tensor World Stress Map Shuttle Radar Topography Mission Generic Mapping Tools Commercial software and publicly unavailable data Motivated by results of computer generated geodynamic models World Stress Map Extensive Database of on the state of stress in the earth from geological and geophysical data http://www-wsm.physik.unikarlsruhe.de/pub/home/index_noflash.html Harvard Centroid Moment Tensor Catalogue Extensive global database of focal mechanisms with magnitude greater than 5.5 since 1977 Easy search functionality Shuttle Radar Topography Mission (SRTM) Provides elevation data at 30 m resolution for much of the earth Easy to produce digital elevation models for large regions http://srtm.usgs.gov/ Outline Earthquakes and Strain Partitioning Depth Distribution of Earthquakes Earthquakes and topography Conclusions Earthquake Kinematics A focal mechanism for an earthquake gives the orientation of the greatest compression (P) and least compression (T) axis Based on the orientations of the P and T axis we can divide the earthquakes into kinematic types Data source: Harvard Centroid Moment Tensor catalogue and World Stress Map Kinematic Types P plunge T plunge Strike Slip <30 <30 Thrust <30 >60 Normal >60 <30 Transpression 30 to 60 30 to 60 P<T Transtension 30 to 60 30 to 60 P>T Strike-Slip Fault P-axis Thrust Fault P-axis Transpressive Fault P-axis Normal Fault T-axis Transtensive Fault P-axis Kinematic Domains 30 29 44 10 23 46 Depth Distribution of Earthquakes Dataset developed for CTBT verification (Bombs) Only events that included a depth phase (pP or sP) were included Data set includes 26 “ground truth events” developed by bomb monitoring community Possible to map brittle & ductile strain Work by Steck, Velasco and others, 1997 Beaumont et al., Nature Relief Map Data Source-SRTM A Possible Explanation Conclusions Major faults in Tibet bound regions of transtension that are likely underlain by a fluid lower crust which is flowing eastward Thrust events are correlated with the range margins, normal faults are correlated with high flat topography This reflects critical taper wedge mechanics coupled with ductile lower crustal flow Publicly available datasets allow examination of large scale problems in the Earth Sciences