Deep syntectonic burial of the Anthracite belt, Eastern Pennsylvania

Mark A. Evans; Aaron M. Jubb

doi:10.1016/j.coal.2024.104646

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Deep syntectonic burial of the Anthracite belt, Eastern Pennsylvania

Mark A. Evans·Aaron M. Jubb

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Abstract

Fluid inclusion microthermometry and Raman spectroscopy of fluid inclusions in quartz veins from the Pennsylvanian rocks of the Anthracite belt, eastern Pennsylvania support a deep burial model of coalification in favor of focused orogenic hot fluid flow. High-temperature (250 to 255 °C) trapping of CH 4 ± CO 2 saturated aqueous fluids and CH 4 ± CO 2 inclusions indicate fluid trapping at depths of 11.5 to 13.4 km under a cover of Pennsylvanian to Permian(?) syntectonic load. In the folded rocks to the south of the Anthracite belt, CH 4 ± CO 2 fluid inclusions indicate a sediment load that was up to 16.3 km thick. Re -equilibrated aqueous fluid inclusions from veins in Silurian through Devonian rocks give the same range of trapping conditions but a wide range of fluid salinities suggesting that folding, fracturing, and meteoric recharge resulted in the intermixing of fluids from throughout the stratigraphic succession.

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International Journal of Coal Geology Article

Source-reported bounding extent: 39.5° to 41.75° latitude; -80° to -75° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Mark A. Evans, Aaron M. Jubb. 2024. Deep syntectonic burial of the Anthracite belt, Eastern Pennsylvania. https://doi.org/10.1016/j.coal.2024.104646

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