Capas rojas triásicas del borde Sureste de la Meseta, síntesis estratigráfica y sedimentológica
ISSN: 0212-4300
Year of publication: 1984
Issue: 3
Pages: 89-105
Type: Article
More publications in: Mediterránea: Serie de Estudios Geológicos
Abstract
The red beds fossilize a highly irregular paleogeography that controlled the localization and evolution of the depositional systems. Triassic sedimentation began during Ladinian with conglomerate deposits that represent the coarsest fractions. Sometimes, they correspond to alluvial fans and other times to conglomeratic braided rivers. In the alluvial fans is possible to differentiate: Inner fan, dominated by debris flow deposits; middle fan, dominated by channel and sheet flood deposits; and outer fan dominated by processes and deposits of conglomeratic braided rivers. Above them andina distal position with respect to the conglomerate deposits there are sandy rivers deposits, of low sinuosity, whose is possible, to differentiate: A) Channel facies, they are represented by very thick sandstone layers (around 15 m.) with cross bedding; B) proximal flood plain facies, represented by thin sandstone layers with cross lamination; which alternate with clay and some carbonate levels of caliche type; and C) distal flood plain facies, characterized by a monotonous clay sucession with very thin layers of micritic limestone and intercalated fine sand of silts. The sedimentation finished in Norian times with the deposition of an evaporitic member of irregular distribution. Its deposition occurred at inundated zones far from the channels or, perhaps, in a sabkha type environment.
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