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Role of Microbes in the Smectite-to-Illite Reaction

J. Kim·H. Dong·J. Seabaugh·Steven W. Newell·D. D. Eberl
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Abstract

Temperature, pressure, and time have been thought to control the smectiteto-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.

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J. Kim, H. Dong, J. Seabaugh, Steven W. Newell, D. D. Eberl. 2004. Role of Microbes in the Smectite-to-Illite Reaction. https://doi.org/10.1126/science.1093245

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