Central New York Association of Professional Geologists

December Dinner Meeting: Larry Brown, Cornell University, "3D Seismic Reflection Imaging with Uncontrolled Sources using Large N Arrays."

  • Wednesday, December 19, 2018
  • 5:00 PM - 8:30 PM
  • Spaghetti Warehouse

Registration

  • Dinner and talk
  • Dinner and Talk
  • Dinner and Talk
  • Dinner and Talk for any student who is not a Student-member of the organization

Register

3D Seismic Reflection Imaging with Uncontrolled Sources using Large N Arrays

Reflection seismology with controlled sources often provides the highest resolution of structure of any seismic technique. However, the application of the reflection method to probe all but the shallowest of structures is often inhibited by the substantial cost of artificial sources as well as logistical barriers to their deployment. Here we describe how reflection processing can be applied to recordings of ambient energy sources, particularly microearthquakes, to produce reflection imagery that approaches the quality of conventional controlled source (CMP) surveys. Such “passive” seismic reflection imaging has only recently become practical with the advent of large N nodal technology that can simultaneously record spatially dense arrays for substantial lengths of time.  Two distinct approaches will be described: seismic interferometry to  re-datum  microearthquakes into virtual surface sources and reverse VSP imaging of microearthquakes. Examples from Iceland, the eastern US and Alaska suggest that these methods represent a transformative approach to imaging deep structure and monitoring active processes in areas illuminated by transient or ongoing microseismicity.

Prof. Brown is the Sidney Kaufman Professor in Geophysics in the Department of Earth and Environmental Sciences. He receive his BS in Physics from Georgia Tech in 1973 and his PhD from Cornell in geophysics in 1976. He has been on the faculty at Cornell since 1977. Prof. Brown's research specialty is high resolution imaging of the lithosphere using seismic reflection techniques. Prof. Brown was a Principal Investigator for the COCORP (Consortium for Continental Reflection Profiling) program which pioneered the application of oil exploration seismic techniques to the study of deep crustal structure in the U.S. He has subsequently been PI for the URSEIS initiative  across the Urals for central Russia and the INDEPTH initiative across Tibet. He has also directed field work to seismically image deep structure across Taiwan, the Andes mountains and on an active Caribbean volcano. His current work is focused on using ambient seismic sources (e.g. earthquakes, cultural noise) to image deep structure in both 3D and 4D using reflection techniques, especially structure associated with earthquake and volcanic processes. Of particular interest is the use of large N, high density seismic arrays for imaging of active subsurface processes using both artificial and natural sources, an approach with great potential for monitoring of, and imaging with, microearthquakes associated with aftershock sequences, magma movement, geothermal production and hydraulic fracturing.



  • Home
  • December Dinner Meeting: Larry Brown, Cornell University, "3D Seismic Reflection Imaging with Uncontrolled Sources using Large N Arrays."
Copyright CNYAPG, All rights reserved
Powered by Wild Apricot Membership Software