Tectonic brines and sedimentary basins: further applications of fission track analysis in understanding Karoo Basin evolution (South Africa)

摘要

AbstractFission track analyses of detrital components in the Permo‐Triassic Karoo Basin (South Africa), highlight the potency of tectono‐magmatically driven fluids to penetrate wide and far in foreland basins. The data, together with the data published on Karoo tectonics and magmatism, support a model which requires that fluids were driven north out of the Cape‐Karoo orogen during the Cape Orogeny (270–200 Ma). Later fluids were redistributed and aquifers rejuvenated during (and after) the final break‐up of Gondwana (<200 Ma). The fission track data indicate that thermal annealing of fission tracks in zircon occurs non‐uniformly between individual zircon grains. This model is in agreement with recent models applied to deformed foreland basins and implicates tectonic fluids in U met