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The AAPG/Datapages Combined Publications Database
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On the assumption that the Louann Salt mass extends below the Gulf of Mexico basin, its volume is calculated at about 4 million km3. If such an amount of salt is added to the volume of present ocean water, together with other post-Paleozoic salts in Africa and the Middle East, the ocean water at the close of the Paleozoic is found to be at least 20 percent saltier than that of the present. The evidence of extinction of many forms of marine life at the close of the Paleozoic probably reflects the inability of marine animals to survive in such salty waters, but it also suggests that such saltiness was not typical of Paleozoic seas and was a consequence of Permian climatic and weathering conditions.
The extraction and accumulation of the Louann Salt mass required prolonged continuance of evaporating conditions. The extensive presence of eolian sandstone in the Triassic System of North America, South America, Africa, Antarctica, Australia, and Europe indicates that desert and semiarid regions probably were far more extensive then than now, and that highly evaporative winds were the agencies affecting the return to normal oceanic salinity as the Louann Salt was deposited. In turn, surviving animal stocks were able to proliferate and fill the Jurassic seas.
It is probable that these conditions also exercised significant control in accumulation of such nonmetallic deposits as phosphates, uranium, potash, sulfur, and bauxite.
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