As the Triassic gave way to the Jurassic, wind spread salmon-red colored sand across the red beds of the Chugwater Formation to form the Nugget Sandstone.
42.
The ferric oxides, which are responsible for the red color of red beds, typically occur as a coating on the grains of sediments comprising red beds.
43.
Initially during the Triassic through early Jurassic, tensional deformation created a series of basement grabens and half grabens, which filled with terrestrial red beds and volcanic rocks.
44.
Fossils have been found from the Dark Red Beds of the Lower Lufeng Formation in Yunnan, China, dating back to the Sinemurian stage of the Early Jurassic.
45.
They are linked to the uplift, erosion and surface weathering of previously deposited sediments and require conditions similar to primary and diagenetic red beds for their formation.
46.
This change in color has been interpreted to reflect bleaching beneath an unconformity that separates red beds of the Nankoweap Formation from dark-gray dolomites of the Galeros Formation.
47.
Abo is also the geological type locality for the Abo Formation, which is made up of sandstone red beds and is exposed to the northwest of the Abo ruins.
48.
However, near the end of Devonian time, the sea was rapidly retreating westward and the continental red beds of the Hampshire Formation were being deposited over most of the State.
49.
Johnson et al . ( 1997 ) have also showed how secondary reddening phases might be superimposed on earlier formed primary red beds in the Carboniferous of the southern North Sea.
50.
Examination of the rock encasing the skull shows it is probably from the Red Beds of the Nanxiong Formation, which date to the Cretaceous Paleogene boundary about 66 million years ago.
