Application of binomial-edited CPMG to shale characterization

Kathryn E. Washburn; Justin E. Birdwell

doi:10.1016/j.jmr.2014.06.014

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Application of binomial-edited CPMG to shale characterization

Kathryn E. Washburn·Justin E. Birdwell

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Abstract

Unconventional shale resources may contain a significant amount of hydrogen in organic solids such as kerogen, but it is not possible to directly detect these solids with many NMR systems. Binomial-edited pulse sequences capitalize on magnetization transfer between solids, semi-solids, and liquids to provide an indirect method of detecting solid organic materials in shales. When the organic solids can be directly measured, binomial-editing helps distinguish between different phases. We applied a binomial-edited CPMG pulse sequence to a range of natural and experimentally-altered shale samples. The most substantial signal loss is seen in shales rich in organic solids while fluids associated with inorganic pores seem essentially unaffected. This suggests that binomial-editing is a potential method for determining fluid locations, solid organic content, and kerogen–bitumen discrimination.

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Kathryn E. Washburn, Justin E. Birdwell. 2014. Application of binomial-edited CPMG to shale characterization. https://doi.org/10.1016/j.jmr.2014.06.014

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