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The AAPG/Datapages Combined Publications Database
AAPG Bulletin
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The Dutch Creek, Beauvais, Lupus, and Hoing Sandstones are supermature quartzarenites associated with transgressive carbonate sequences. They generally have gradational upper and lower contacts. Fossils are mostly fragmentary crinoids, brachiopods, and trilobites. Complete fossils are mostly corals that settled during periods of temporary bottom stability and slow sedimentation.
Unidirectional, planar cross-bedding dominates part of the Dutch Creek, Beauvais, and Lupus Sandstones, indicating paleocurrent movement to the northwest. Local herringbone cross-stratification with associated reactivation surfaces indicates tidal action. Lenticular bodies of Hoing and Lupus sandstone enclosed in calcilutite contain graded sequences and basal conglomerates, suggesting tidal-channeling of banks and shoals. Parallel lamination and cylindrical structures in the Hoing Sandstone indicate high intertidal environments.
These sandstones all consist of bimodally distributed fine- and medium-sized quartz grains. Medium-sized grains are well rounded to rounded, contrasting with angular fine-grained quartz. Cementation is mostly by sparite and microcrystalline calcite. Locally, secondary silica replaces carbonate. Near faults, quartzitic texture probably results from pressure solution. Interlocking secondary overgrowth locally provides cementation.
Bimodal grain-size distribution, seaward thickening of the sandstone, and an apparently inadequate source suggest eolian transport to the sea across a carbonate terrane prior to marine deposition. This does not require a sabkha, but depends on aridity and sparse plant cover. Subsequent tidal, wave, and current action is believed responsible for ultimate transport and deposition of the sand.
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