The Proceedings of the Eighth International Conference on Creationism (2018)
Borsch et al. ◀ Micas in ancient sandstones ▶ 2018 ICC 325 Tensleep Sandstone Wyoming (Pennsylvanian) Agatston 1952; Kerr and Dott 1988*; Mankiewicz and Steidtmann 1979* The Tensleep Sandstone of Wyoming correlates with the Quadrant Sandstone of Montana, the Weber Sandstone of Utah and the Casper and Minnelusa Sandstones of Wyoming and South Dakota. It is about 55 m thick at its type section near Ten Sleep, Wyoming (Mankiewicz and Steidtmann 1979). Based on Pennsylvanian marine fusilinids, carbonate cement and limestone and dolomite beds, it was originally thought to be entirely a shallow marine deposit (Agatston 1952; for a summary see Kerr and Dott 1988). However, others now believe it to be eolian (especially the upper part) based on its very fine to fine-grained quartz-rich sands, sorting, wind-ripple laminae, grainfall strata, avalanche strata and large-scale tabular-planar cross-beds with dips of 19-34º (Kerr and Dott 1988; Mankiewicz and Steidtmann 1979). Weber Sandstone Utah, Colorado (Pennsylvanian) Doe and Dott 1980*; Fryberger 1979* According to Fryberger (1979) the Weber has multiple evidences for the eolian origin of its beds including large scale cross-beds, raindrop imprints, contorted stratification, well-sorted quartz sandstones (with interbedded fluvial deposits). However, he does recognize that parts of the Weber further to the west are marine. Fryberger measured several sections of Weber in the Dinosaur National Monument Area; the section in Sand Canyon was 280 m thick. He reported that the Weber is correlative with the Tensleep Sandstone of Wyoming and the Wells Formation of northeastern Utah. White Rim Sandstone Utah (Permian) Baars and Seager 1970; Baars 2010; Blakey et al. 1988*; Chan 1989*; Tubbs 1989*; The best exposures of the White Rim Sandstone occur in the vicinity of Canyonlands National Park, Utah where it forms a “white rim” around much of the Colorado and Green River canyons. The sandstone probably correlates with the upper portion of the Coconino (Blakey et al. 1988). Its greatest thickness is about 80 meters (Chan 1989). Baars and Seager (1970) thought that the sandstone represented a nearshore shallow marine bar, a view which Baars still held in 2010. But, Tubbs (1989) and most others now identify the White Rim as a coastal dune deposit based on wind-ripple strata, sandflow toes, raindrop imprints, planar bounding surfaces, eolian textural trends, high percentage quartzose composition, lack of clay and silt in the deposit and deformational features. Yellow Sand England (Permian) Steele 1983*; Versey 1925*; Pryor 1971 The Lower Permian Yellow Sand is usually described as fine- to coarse-grained and is said to consist of well-sorted, well-rounded to subangular clasts with common “frosting” of grain surfaces. Versey (1925) claimed that the Yellow Sand was the product of eolian processes, which is still the dominant view. However, Pryor (1971) challenged the eolian interpretation and argued that the Yellow Sand was deposited as a series of submarine sand ridges comparable to those from the modern North Sea shelf. He presented petrographic data showing that the Yellow Sand is in fact only poorly to moderately sorted, mostly subrounded, with <15% of the constituent grains being well-rounded and substantial amounts of subangular and angular grains. He documented the presence of muscovite and found cross-bed dips were about 18 ° . Pryor (1971) argued that these features were indicative of a shallow marine origin, although his reinterpretation has not been generally accepted.
Made with FlippingBook
RkJQdWJsaXNoZXIy MTM4ODY=