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Biogeochemistry of microbial coal-bed methane

January 1, 2011

Microbial methane accumulations have been discovered in multiple coal-bearing basins over the past two decades. Such discoveries were originally based on unique biogenic signatures in the stable isotopic composition of methane and carbon dioxide. Basins with microbial methane contain either low-maturity coals with predominantly microbial methane gas or uplifted coals containing older, thermogenic gas mixed with more recently produced microbial methane. Recent advances in genomics have allowed further evaluation of the source of microbial methane, through the use of high-throughput phylogenetic sequencing and fluorescent in situ hybridization, to describe the diversity and abundance of bacteria and methanogenic archaea in these subsurface formations. However, the anaerobic metabolism of the bacteria breaking coal down to methanogenic substrates, the likely rate-limiting step in biogenic gas production, is not fully understood. Coal molecules are more recalcitrant to biodegradation with increasing thermal maturity, and progress has been made in identifying some of the enzymes involved in the anaerobic degradation of these recalcitrant organic molecules using metagenomic studies and culture enrichments. In recent years, researchers have attempted lab and subsurface stimulation of the naturally slow process of methanogenic degradation of coal.

Citation Information

Publication Year 2011
Title Biogeochemistry of microbial coal-bed methane
DOI 10.1146/annurev-earth-040610-133343
Authors D. Strc, Maria Mastalerz, K. Dawson, J. MacAlady, A.V. Callaghan, B. Wawrik, C. Turich, M. Ashby
Publication Type Article
Publication Subtype Journal Article
Series Title Annual Review of Earth and Planetary Sciences
Series Number
Index ID 70035089
Record Source USGS Publications Warehouse
USGS Organization