3D seismic analysis of sedimentary dynamics from late pliocene to present on the Ebro continental margin

Abstract

Analysis of industry 3D seismic reflection data on the Ebro continental margin was analized to better understand the evolution of the sedimentary dynamics of the Ebro margin shelf from late Pliocene to present, considering the Gelasian-Calabrian boundary transition from a climate dominated by 41 ka Earth precession cycles to 100 ka obliquity of the Earth’s orbit dominated cycles. Time-structure maps of the Gelasian-Calabrian boundary and other reflectors above and below were extracted. It allowed mapping of paleo-river systems and its connection with slope paleo-canyons during the late Pliocene and Pleistocene. Amplitude and coherency attributes were also extracted from the seismic data. The late Pliocene-Quaternary sedimentary dynamic results from the interplay of tectonics, sea-level variations and inherited palaeotopography. Multiple high-frequency and high-amplitude sea-level changes took place during the Quaternary, leading to the progradation of the margin, favoring the development of homogeneous sedimentation and the formation of stream networks in the shelf. These rivers connected to the preexistent submarine canyons bypassing the sediments from the continent to the slope during long-term regressions. Submarine canyons were present before the studied time interval. Tectonic activity might have caused their formation in the upper slope of the ECM