Mehdi Ostadhassan
Paul C. Hackley
Andrew E. Pomerantz
Siamak Nejati
Arash Abarghani
2020
<p><span>Organic matter (OM) from various biogenic origins converts to solid bitumen </span><i>in-situ</i><span> when it undergoes thermal maturation. It is well documented that during this process, the ratios of both hydrogen and oxygen to carbon will decrease, resulting in an increase in OM aromaticity and molecular chemo-mechanical homogeneity. Although there have been extensive efforts to reveal molecular alteration occurring to OM during conversion, </span><i>in-situ</i><span> and continuous observation of such alterations on naturally occurring samples is missing. Therefore, evaluation of previous results cannot be made independent from natural sample variability. In this study, we identified OM particles (</span><i>Tasmanites</i><span>) that are evolving </span><i>in-situ</i><span> into solid bitumen in the Bakken Formation. This </span><i>in-situ</i><span> bituminization allows examination of a continuous transformation in OM molecular structure at micron-scale using AFM based IR spectroscopy applied at the transition/interface zone. Moreover, contact mode in the AFM was employed to reveal and relate changes in mechanical properties at a similar scale of measurement. Understanding these chemical and mechanical alterations is important to understand shale reservoir properties and better explain hydrocarbon generation, expulsion, and migration processes at the microscale.</span></p>
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10.1016/j.gca.2020.01.019
en
Elsevier
A chemo-mechanical snapshot of in-situ conversion of kerogen to petroleum
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