Consideraciones teóricas sobre el análisis de la subsidencia: aplicación a un caso real en el borde de la cuenca triásica ibérica

Zusammenfassung

Triassic red beds (Buntsandstein) in central Spain (Cordillera Ibérica-Sistema Central connection area) display significant thickness changes and local unconformities that are related to extensional tectonics that ruled the evolution of the Triassic basin. The tectonic movements during the sedimentation resulted in a series of discontinuities in sedimentation together with some local unconformities. A detailed study of the subsidence evolution is necessary to fully understand the paleogeography and geometries of these deposits. A revision of the existing theories about quantitative analysis of subsidence rates and their limitations has been carried out. Tectonic subsidence and total subsidence plots have been constructed far several stratigraphic columns. Sorne of these columns are located in the border of the basin, but some others come from more central areas, where tectonic movements did not generate unconformities. The border of the basin, where tectonics generated a series of tilted fault blocks that gave way to significant thickness and geometries changes, has been detailed studied assuming a local isostatic compensation. The amount of lithospheric stretching (ß) displays a great variability, mainly the values related to the border of the basin.