ORIGIN OF CENOMANIAN NODULAR PHOSPHORITES IN THE DNIEPER-DONETS DEPRESSION (PALEOGEOGRAPHIC ASPECT)

Abstract

Paleogeographic settings of the Dnieper-Donets Depression are discussed with consideration of its Cenomanian provenance, land-sea proportions, and paleoclimate. The role of the Jurassic-Cretaceous weathering crust that stimulated the formation of phosphate solutions and the accumulation of apatite-ilmenite placer deposits is emphasized. Based on global regularities in the phosphorite formation, it is stated that weathered areas of adjacent land, rather than the World Ocean, represented the main source of phosphorus in ancient platform basins. © Pleiades Publishing, Inc. 2006.