Reservoir Characterization Using Seismic Reflectivity and Attributes

Abdulrahman Mohammad Saleh Al-Moqbel

Submitted to the Department of Earth, Atmospheric, and Planetary Sciences on May 7, 2002 in partial fulfillment of the requirements for the degree of Master of Science

Abstract

The primary objective of this thesis is to obtain reservoir properties, such as porosity from surface seismic data complemented by available well logs. To accomplish this a two-step procedure is followed. First, reflectivity and acoustic impedance profiles are obtained from the inversion of post-stack seismic data. Second, a multi-attribute analysis, calibrated using well logs, is used to obtain porosity.

This procedure is applied to a 40x40 sq. km field data set from the eastern region of Saudi Arabia. The 3-D seismic data are of good quality. Twenty-one wells have a good suite of logs. The analysis is focused on the reflections from the reservoir.

The outcome of the thesis is an improved subsurface image of the seismic data, a porosity prediction for the reservoir, and a reservoir quality map obtained by similarity analysis using one of the wells as reference.