Formulation of a Porosity Operator for Joint Interpretation of Resistivity and Microearthquake Data Across a Fluid-Filled Fracture Zone

Abstract

This paper presents a formulation of a porosity operator that can be used as the basis for joint interpretation of microearthquake and resistivity data across a fluid-filled fracture zone. The use of resistivity and microearthquake measurements is based on theoretical formulation of shared porosity, fluid content and temperature. The relation of resistivity and a double porosityoperator is solved using a basis function. The conceptual model used to formulate the porosity operator over a buried, fluid-circulating fault zone in hydrothermal systems is based on geological and fracture models. The porosity-operator is solved by a basis function and then used to generate a correlation function between P-wave velocity and resistivity. This correlation is then used to generate P-wave velocity and porosity models from 2-D resistivity models generated from magnetotelluric (MT) data through a porosity operator derived from a modified double porosity model.