Sedimentary structures
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Sedimentary structures include all kinds of features in sediments and sedimentary rocks, formed at the time of deposition.
Megaripple/dune, formed in the upper flow regime, from Utah
Wave ripple or symmetric ripple, from Permian rocks in Nomgon, Mongolia with "decapitation" of ripple crests due to change in current
Skolithos trace fossil (scale bar is 10 mm)
Soft sediment deformation (possibly a seismite) in Dead Sea sediments, Israel
Cross-bedding
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In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal un
Sedimentary structures
…each other. These beds range from millimeters to centimeters thick and can even go to meters or multiple meters thick. Sedimentary structures such as cross-bedding, graded bedding, and ripple marks are utilized in stratigraphic studies. They help indicate the original position of strata in geologically complex…
Cross-bedding of sandstone near Mt. Carmel road, Zion Canyon, indicating wind action and sand dune formation had occurred prior to formation of the rock.
Cross-bedding in a sandstone dome in the Canyons of the Escalante.
Sand dune cross-beds can be large, such as in the Jurassic-age erg deposits of Navajo Sandstone in Canyonlands National Park. Aztec Butte shown here
Schematic of aeolian cross-bedding