Arquitectura secuencial en cuencas lacustres someras (Mioceno de la Cuenca del Duero). Analogías y diferencias con los principios de la estratigrafía secuencial

Abstract

Sequence stratigraphy principles are compared to similar geometrica architectures in lacustrine sediments of Miocene age in the Duero Basin (NW Spain). The studied sequence shows an erosive base wirh multiple scours, a lower reach that shows an aggradational pattern, first deepening and later and mostly shallowing upward, foffowed by an upper reach composed by prograding c1inoforms deeper than the immediately underlying deposits. The upper boundary of lhe sequence is another erosive surface with multiple scours. This sequence can be compared to a type 2 sequence al Van Wagoner et al. (1988). Despite the similarities concerning geometries and their evolution, there are some differences about water depth evolution and thus about facies evolution thaat show reverse relations in the sequence stratigraphy model and our lacustrine case. Similarities are due lO common evolulion of base level in both cases. Differences arise from the different amount of influence of sedimentation and subsidence in marine and lacustrine systems.