Applied Coal Petrology

Chapter 9. Coal as a Petroleum Source Rock and Reservoir Rock

9.1. Introduction

A consensus has existed for many years that oil and natural gas are derived principally from the thermal and biological decomposition of organic matter. Coal is defined as a rock composed of more than 50% organic matter by weight and is thus by definition the rock type that is richest in organic matter. For this reason, coal is considered an important petroleum source rock, and the ways in which petroleum compounds can be generated and expelled from coal is a subject of vigorous debate (e.g., Wilkins and George, 2002). Coal is also an important reservoir for natural gas, and gaseous hydrocarbons produced from coal are commonly referred to as coalbed methane (e.g., ...