Robert Evans, 1977. "Origin and Significance of Evaporites in Basins Around the Atlantic Margin", Geology of Continental Margins, Joseph R. Curray, William R. Dickinson, Wallace G. Dow, Kenneth O. Emery, Donald R. Seely, Peter R. Vail, Hunter Yarborough
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Immediately before the rifting and disruption of Pangaea, that great continent lay athwart the Triassic equator. The continental interior was arid, and isostatic adjustments following rifting produced drainage flowing away from the newly-formed elongate troughs. These climatic and physiographic conditions led inevitably to the deposition of evaporites as the sea entered the rift zones whose margins now form the edges of the continents around the Atlantic. As a result, the sediment sequence in the Atlantic coastal basins shows a change from continental to evaporitic to normal marine conditions, except where evaporites were deposited directly onto newly-formed oceanic crust. The age of these evaporites gives a chronology for the establishment of a permanent body of water between the separting fragments of Pangaea. The North Atlantic appeared in the north in late Triassic time and became established further south by Middle Jurassic. The South Atlantic became established during Aptian time. The Gulf of Mexico came into existence in Middle Jurassic time by the subsidence of continental material. The union of the two parts of the incipient ocean came about during or later than Albian time and the resulting free circulation of water in the Atlantic eliminated the restriction necessary for the continued accumulation of evaporite deposits. No such deposits are known, therefore, from the northern coast of Brazil or from the northern side of the Gulf of Guinea.
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Geology of Continental Margins
Written in 1977 the publication presents interpretations of then-new data bearing on the geology and geophysics of continental margins. The book includes a discussion of plate tectonics and evolution of continental margins; presentations on the stratigraphy and structure of pull-apart and compressional margin;, prospective petroleum source rocks, their organic content, rate of burial, and distribution on slopes and rises of different margin types; prospective reservoir rock patterns in relation to depositional processes and to the sedimentary and structural histories for different types of continental margins; and seismic recognition of depositional facies on slopes and rises for different margin types with varying rates of sediment supply during eustatic sea-level changes.