Rasgos sedimentarios indicadores de inestabilidad causada por actividad tectónica sismogenética. Las cuencas neógenas de las minas de Hellín y Cenajo (Prebético Externo, SE de España)

Resumo

The sedimentary infilling of the Neogene basins of Las Minas de Hellín and Cenajo, in the External Prebetic Zone (SE Spain), shows a variety of features indicative of instability that resulted from seismogenetic tectonic activity. Soft-sediment deformation structures such as sand dikes, pillows, mushroom structures, mixed layers, disturbed varved lamination, and others are commonly recognised in the Neogene deposits and are interpreted as resulting from episodic seismic events (seismites). Redeposited beds reaching up meters to tens of meters in size are also recognised and interpreted as indicative of seismic shocks that affected the sedimentary infill of the basins. An additional feature deals with local occurrence of carbonate mounds interbedded with the sedimentary deposits of the Las Minas de Hellín Basin. The mounds consist mainly of highly lithified, strongly folded and fractured and locally replaced by silica carbonate beds that occur closely related to the main faults of the basin.