The southern Washington Cascades conductor: A previously unrecognized thick sedimentary sequence?

W. D. Stanley; W. J. Gwilliam; Gary Latham; Keith Westhusing

doi:10.1306/bdff8a56-1718-11d7-8645000102c1865d

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The southern Washington Cascades conductor: A previously unrecognized thick sedimentary sequence?

W. D. Stanley·W. J. Gwilliam·Gary Latham·Keith Westhusing

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Abstract

Geophysical studies in the southern Washington Cascades have outlined a possible, previously unrecognized sequence of sedimentary rocks. These postulated sedimentary units are interpreted to correspond to at least the upper section of a low-resistivity (high-conductivity) assemblage of rocks at depths of 1-10 km and with thicknesses up to 15 km that called the southern Washington Cascades conductor. Structure on the upper surface of this conductive assemblage correlates in some places with anticlines that bring Tertiary marine rocks near the surface. The geometry of the conductive rocks consists of a east-dipping, low-angle wedge that thickens to the north and with an undulating upper surface corresponding to the anticlines. Geothermal fluids may be a contributing factor to low resistivities in the deeper parts of the conductive section. -from Authors

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American Association of Petroleum Geologists Bulletin Article

Source-reported bounding extent: 46.10926604734689° to 47.09217717972356° latitude; -123.0476092389447° to -120.81643027066724° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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W. D. Stanley, W. J. Gwilliam, Gary Latham, Keith Westhusing. 1992. The southern Washington Cascades conductor: A previously unrecognized thick sedimentary sequence?. https://doi.org/10.1306/bdff8a56-1718-11d7-8645000102c1865d

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