Ellis, Leroy¹
(1) Isotope Logging, Inc. (ISOLOG), Richardson, TX

ABSTRACT: Mud Gas Isotope Logging (MGIL) – A bona fide Geochemical Success Story in Contemporary Hydrocarbon Exploration

Advances in sampling and analytical techniques now permit the isotopic analysis of very small amounts of hydrocarbon gases in air that are collected from the circulating mud stream during drilling. A recently developed technique termed Mud Gas Isotope Logging (MGIL) has found considerable application and continued success in global hydrocarbon exploration operations. MGIL has now been adopted and implemented by most major oil companies as a standard well logging protocol or ‘best practice’ in drilling operations. MGIL technologies are not restricted to oil majors, with smaller independents adopting these technologies as more company geologists and geoscientists become familiar with the technique and interpretation. MGIL helps validate hydrocarbon-charged intervals identified by standard mud gas or wireline techniques, assess vertical reservoir compartmentalization, and identifies possible bypassed or low-resistivity pays. Benefits for regional exploration are assessment of sealing intervals, charge history, and thermal maturity of hydrocarbons. New ‘deployable instrument’ developments debuting in 2004 appear set to revolutionize existing MGIL acquisition technologies in E&P drilling operations. In this talk we examine recent case histories, future applications, and results of mobile MGIL field tests leading up to commercial introduction of such new instruments and technologies.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.