Deep-Water Sandstones, Brushy Canyon Formation
R. T. Beaubouef, C. R. Rossen, F. B. Zelt, M. D. Sullivan, D. C. Mohrig, D. C. Jennette, J. A. Bellian, S. J. Friedman, R. W. Lovell, D. S. Shannon, 1999. "Deep-Water Sandstones, Brushy Canyon Formation", Deep-Water Sandstones, Brushy Canyon Formation, West Texas, R. T. Beaubouef, C. R. Rossen, F. B. Zelt, M. D. Sullivan, D. C. Mohrig, D. C. Jennette, J. A. Bellian, S. J. Friedman, R. W. Lovell, D. S. Shannon
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Exceptional oblique-dip exposures of submarine fan complexes of the Brushy Canyon Fm. allow reconstruction of channel geometries and reservoir architecture from the slope to the basin floor. The Brushy Canyon conslsts of 1,500 ft. of basinally restricted sandstones and siltstones that onlap older carbonate slope deposits at the NW margin of the Delaware Basin. This succession represents a lowstand qequence set comprised of lugher frequency sequences that were deposited in the basin during subaerial exposure and bypass of the adjacent carbonate shelf. Progradational sequence stacking patterns reflect changing position and character of the slope as it evolved from a relict, carbonate margin, to a constructional, siltstone-dominated slope. Lowstand fan systems tracts consist of sharp-based, laterally extensive, sand-prone basin floor deposits and large, sand-filled channels encased in siltstones on the slope. The abandonment phase of each sequence (lowstand wedge-transgressive systems tract) consists of basinward-thinning siltstones that drape the basin floor fans. The slope-tobasin distnbution of lithofacies is attributed to a three stage cycle of: 1) erosion, mass wasting, and sand bypass on the slope with concurrent deposition from sand-rich flows on the basin floor, 2) progressive backfilling of feeder channels with variable fill during waning stages of deposition, and 3) cessation of sand delivery to the basin and deposition of laterally-extensive siltstone wedges. Paleocurrents and channel distributions indicate SE-E sediment transport from the NW basin margin via closely spaced point sources.