Características y factores de control del relleno sedimentario reciente en los fondos de la bahía de Cádiz

Abstract

To know the characteristics of the recent sedimentary infilling of the Cadiz bay sea bottom and adjacent continental shelf, a non consolidate recent sediments isopachs map has been made, based on geophysical and submarine data, so as representative geological sections of infilling structure. Thickness distribution presents significative variation, according to the characteristics of each sector: Large thickness are related to paleochannels zones, which follow clearly structural tend. Low thickness are in littoral areas and close to rocky shoal. Isopach distribution and depocenters layout is influenced by morfoestructural control of sedimentary processes.

The upper part of sedimentary infilling presents deposits of variable textural and compositional character with preponderance of quartz in sandy bed and illite in sandy-mud. These characteristics suggest the importance of terrigenous sedimentation wich is controlled by continental runoffs with alternance of more reworking and great sedimentation rate stages and others controled by acomodation. These processes are the consecuence of successive sea level changes that ocurred during the last stages of the Holocene