Passive Seismic Tomography

Geysers2009_Pvel_3km_depthPassive Seismic Tomography (PST)  is a technique developed in the early 80s by K. Aki and students at MIT to image the subsurface of the earth. For sources in PST we use small earthquakes instead of explosions or vibroseis, as is used in traditional active source acquisitions. Thus for PST, we need an active tectonic region where there is microseismicity that can be used as a source. Any  tectonically active region can be imaged using PST, provided there are enough earthquakes beneath and in and around the target of interest. Let ISTI develop a monitoring solution for your region of interest. We have the expertise, hardware, and staff to provide you with a complete end-to-end PST solution or if you already have a network running, we can use your data with our workflow to provide you with a complete 3D image.

TomoMapDepthSliceTomoSection_P_velTomoSection_PercentDiff

ISTI has developed an efficient workflow for processing data from a microseismic network to produce a 3D velocity image using our PST techniques. ISTI’s seismologists Ilya Dricker and Paul Friberg have been performing PST for industry using advanced techniques for many years (i.e., we use finite difference Eikonal equation solvers for ray tracing). ISTI works with leading researchers in this field to improve the algorithms in our workflow and to also provide high precision relative locations using double-differencing techniques (Waldhauser and Ellsworth, 2000) also using 3D velocity models.