Abstract Title: 3-D JOINT INVERSION OF SEISMIC AND ELECTROMAGNETIC DATA FOR 
RECOVERING COMPLEX GEOLOGICAL STRUCTURE IN THE GREAT BASIN REGION

Abstract Author(s): Zhdanov, Michael (University of Utah) - Golubev, Nikolay 
(University of Utah)
  
Abstract: The unique geological structure of the Great Basin region is very 
important both for the study of its geodynamical history, and for understanding 
those physical processes controlling earthquakes and volcanic eruptions. For 
such a complex region, definitive structural interpretations based purely on 
seismological observations may not be sufficient for reliable study of the deep 
earth interior. To this end, additional and important contributions to this 
study could include the use of electromagnetic (EM) techniques, such as the 
magnetotelluric (MT) method. MT data can potentially provide independent 
information about the structure and temperature regime interpreted from the 
electrical conductivity. The interpretation of MT observations can assist to 
determine the geometry of the lithosphere. For models with geometry fixed by 
seismic observations, it could be possible to localize zones of lithospheric 
melting or asthenospheric upwelling. The scope for joint three-dimensional 
(3-D) inversion of both seismic and MT data offers the opportunity to improve 
geological interpretations developed by either method alone. Such 3-D 
interpretation requires fast and accurate methods of modeling large-scale 
problems. A family of 3-D MT modeling algorithms has been developed based on 
integral equation and finite-difference methods. The codes have been partially 
adapted for parallel computing and are available for large-scale modeling and 
interpretation of regional scale MT data observations. Though the joint 
inversion of seismic and MT data are currently not available, such a project 
would provide a very interesting avenue for future research. The goal of the 
integrative interpretation is to obtain reliable information to improve 
geological understanding, including thermal regime estimates, future earthquake 
locations and depth range of seismicity.