Role of Microbes in the Smectite-to-Illite Reaction

• Published in: Science (American Association for the Advancement of Science) Vol. 303; no. 5659; pp. 830 - 832
• Main Authors: Kim, Jinwook, Dong, Hailiang, Seabaugh, Jennifer, Newell, Steven W., Eberl, Dennis D.
• Format: Journal Article
• Language: English
• Published: Legacy CDMS American Association for the Advancement of Science 06-02-2004; The American Association for the Advancement of Science
• Subjects: Aluminum Silicates; Bacteria; Chemical properties; Chemical reactions; Clay minerals; Climate; Crystallization; Crystals; Diagenetic processes; Earth sciences; Earth, ocean, space; Electrons; Exact sciences and technology; Ferric Compounds - metabolism; Ferrous Compounds - metabolism; Hydrocarbons; Identification and classification; Illite; Life Sciences (General); Microorganisms; Microscopy, Electron, Scanning; Mineralogy; Minerals; Minerals - chemistry; Minerals - metabolism; Organic Chemistry; Oxidation-Reduction; Petroleum; Pressure; Shewanella - metabolism; Siderite; Silicates; Silicates - chemistry; Silicates - metabolism; Smectite; Spectroscopy; Temperature; X-Ray Diffraction; United States; diagenesis; illite; models; bacteria; ferric iron; dissolution; ferrous iron; X-ray diffraction; TEM data; X-ray spectroscopy; smectite; prokaryotes; chemical reduction; microorganisms; transformations; clay minerals; sheet silicates; silicates; P-T conditions; biogenic effects; transmission electron microscopy; kinetics; petroleum exploration
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1093245

Temperature, pressure, and time have been thought to control the smectite-to-illite (S-I) reaction, an important diagenetic process used for petroleum exploration. We demonstrated that microorganisms can promote the S-I reaction by dissolving smectite through reduction of structural Fe(III) at room temperature and 1 atmosphere within 14 days. This reaction typically requires conditions of 300° to 350°C, 100 megapascals, and 4 to 5 months in the absence of microbial activity. These results challenge the conventional concept of the S-I reaction and of reaction kinetic models.