Using a combination of geological, 3D seismic, and magnetotelluric (MT) data, we explore the use of advanced analytics to understand and define areas of high permeability within the Raft River geothermal resource area The primary focus is on 3D seismic reflection and a 3D resistivity volume, but it is supplemented with other available datasets. The 3D seismic reflection data includes multiple seismic attributes (amplitude, energy, semblance, correlation, and texture), as well as the fundamental physical properties of density and velocity. The MT data has been reprocessed to generate resistivity and spatial gradients of resistivity. Both datasets have been co-registered onto the same coordinate system. We see clear correspondence between the geophysical measurements and the known geology. Resistivity clearly separates three lithological units: Raft River formation (low resistivities), Salt Lake formation (intermediate resistivities), and the basement (very high resistivities). The boundary between the basement and the overlying sediments appears to be distinct in both the seismic attributes and the MT, although the exact details and relationship to previously inferred structure such as the Narrows structure and Bridge Fault Zone are unclear at present. The goal is to explore the possibility of using the combined seismic and MT data in a predictive fashion to define productive zones. This analysis is based on python-driven Jupiter notebook using scipy, which allows for easy collaboration between partners. This first step has been to use K-cluster analysis to independently evaluate differences between lithologic formations. The results are compared with the known formations as based on well log data and mapped seismic horizons. The cluster analysis reveals that the interface between basement and the overlying geology stands out clearly. This is the primary productive zone of the geothermal reservoir. Prepared by LLNL under Contract DE-AC52-07NA27344.

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