Abstract

We present the basic theory of rock physics, laboratory studies, and field observations that can be applied to interpreting tomographic solutions from microearthquakes for reservoir properties. These properties include location of fluids, fractures, porosity, and permeability. We obtain 3D tomographic solutions for isotropic velocity (Vp and Vs) and attenuation (Q p and Qs), and derived solutions for elastic moduli (lambda, bulk and Young's), and Poisson's ratio. We show that a relatively high density of recording stations, about one each km<sup>2</sup> , and relatively few microearthquakes (˜300) can provide solutions at sufficient resolution and in a relatively short amount of time to be useful for reservoir exploration and management. We provide a case study for The Geysers, California, USA.

Keywords: tomography, reservoir modeling, microearthquakes, rock physics, The Geysers
