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Oxygen-isotope, X-ray-diffraction and scanning-electron-microscope examinations of authigenic-layer-silicate minerals from Mississippian and Pennsylvanian sandstones in the Michigan Basin

K.F. Zacharias·D.F. Sibley·D.B. Westjohn·T. L. Weaver
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Abstract

Oxygen-isotope compositions of authigenic-layer silicates (<2-micrometer fraction) extracted from Mississippian and Pennsylvanian sandstones in the Lower Peninsula of Michigan were determined. Petrographic and scanning-electron-microscope examinations, and X-ray diffractograms show that chlorite and kaolinite are the most common authigenic-layer silicates in Mississippian sandstones. The range of oxygen-isotope compositions of chlorite and kaolinite are +10.3 to +11.9 and +12.9 to +19.3 pars per thousand (per mil) (relative to Standard Mean Ocean Water), respectively. Kaolinite is the only authigenic-isotopic compositions of kaolinite range from +16.8 to +19.0 per mil.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 42.04521345501039° to 44.68427737181225° latitude; -86.4898681640625° to -82.6666259765625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K.F. Zacharias, D.F. Sibley, D.B. Westjohn, T. L. Weaver. 1993. Oxygen-isotope, X-ray-diffraction and scanning-electron-microscope examinations of authigenic-layer-silicate minerals from Mississippian and Pennsylvanian sandstones in the Michigan Basin. https://doi.org/10.3133/ofr93103

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