Sismoestratigrafia y evolución geomorfológica del talud continental adyacente al litoral del este bonaerense, Argentina

introduction the argentina continental margin (mca) is one of the largest margins around the world (2x106 km2), which in most of its area of development (between 35 and 48os) belongs to a typical extensional volcanic passive margin (mohriak et al., 2002). the region is located in a key area of the southwestern atlantic ocean due to its significance in the global oceanographic-climatic interaction (wefer et al., 1996, 2004; carter and cortese, 2009). as a result, the study of the cenozoic sedimentary sequences preserved in the geological record is very important for paleoceanographic-paleoclimatic-paleoenvironmental reconstructions. the study area is included in the northern part of the mca adjacent to eastern buenos aires province (fig. 1a). the major physiographic units are the shelf, slope, rise and the mar del plata submarine canyon. this work describes the cenozoic morphosedimentary, stratigraphic and evolutive aspects of the continental slope in the region. the study is based on high resolution seismic (multi and monochannel) complemented with sediment analysis on piston and gravity cores as well as grab samples (fig. 1b), obtained during different cruises on board the research vessels puerto deseado (argentina) and meteor (germany) (table 1); additional seismic, geological and sedimentological information was gathered from ldeo (usa) and bgr (germany). geotectonic, morphosedimentary and oceanographic setting the region (fig. 1a) is located in the southern part of the salado basin where post-cretaceous sediment thickness varies between 2 and 4 kilometers. stratigraphic information from offshore oil drillings (fig. 2) indicates that in the outer shelf, immediately west of the study area, sedimentary sequences are represented by maastrichtian-paleocene marine deposits, eocene-oligocene continental deposits, miocene marine deposits, pliocene continental deposits and quaternary marine deposits (yrigoyen, 1975, 1999; tavella and wright, 1996). these sequences change