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Palynomorphs from the High Atlas Mountains south of Marrakech define the Minutosaccus-Patinasporites Concurrent Range Zone, which is time-stratigraphically equivalent to the Swiss and English middle Keuper, type Carnian of Austria, and North American Triassic beds in Virginia, North Carolina, Pennsylvania, New Jersey, Texas, New Mexico, and Arizona, thus dating an early episode of continental rifting between Africa and North America.

Factors controlling the concentration of titanium-iron oxides in the sands of the Cohansey Formation of New Jersey include source rock, climate, and depositional environment. The microtextures of the titanium-iron oxides in the Cohansey sands match those in Precambrian gneisses that crop out in the New Jersey highlands and eastern Pennsylvania. Palynological evidence indicates a warm subtropical climate during titanium-rich sand deposition. Such a subtropical environment favors deep saprolitic weathering of the source rock.The highest heavy mineral values (5-25 wt %) found in the Cohansey Formation correlate with the highest degrees of sorting (standard deviation 0.5-0.8), with positive to slightly negative ske•vness (0.8--0.4), and with a laminated and burrowed sand facies found in the lower portion of the formation. Peat interbedded with titanium-rich sand contains subtropical palynomorph suites and dinofiagellates. The peat is interpreted as a lagoonal deposit that was flooded with marine water. The titanium-iron oxide-rich sands are interpreted as a backshore beach and dune facies that was preceded by sublittoral Kirkwood Formation sand deposition. Present climatic and physiographic conditions of Georgia and South Carolina, where thick titanium-rich saprolites, fluvial placers, and beach placers occur, are analogous to the conditions that prevailed in the New Jersey area during the deposition of the Cohansey titanium-iron oxide-rich sands. This warm Cohansey event represents the last major Neogene warming trend and on the basis of climatic periodicity modeling coincides with the Miocene-Pliocene boundary.

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