Three-D seismic and well data enabled the high resolution interpretation of a Santonian-age succession in present day shallow waters of Santos basin, Brazilian east continental margin, where recent oil and gas discoveries have been made by OGX Oil & Gas. An organized hierarchical system of depositional sequences was identified. A lower order composite depositional sequence was interpreted from seismic facies, lithofacies distribution and bio-chronostratigraphy. The composite depositional sequence was broken down into its constituent systems tracts, each of them exhibiting characteristic patterns in seismic and well log data. Comprising the lowstand systems tract of the composite depositional sequence are five stratigraphic levels of sandy deposits intercalated with thick hemipelagic shale drapes which constitute the elementary depositional sequences of this systems tract. The sandy deposits are mainly erosion-confined channels and/or channel complexes that increase upward in both size and net sand content, reflecting the increasing energy associated with the erosive processes that carved the channels/channel complexes. A capping sequence containing smaller channel complexes with less net sand content reflects the waning depositional energy at the end of the lowstand system. Crucial to understand the distribution and connectivity of reservoirs, establishment of this sequence stratigraphic framework enabled the recognition and correlation of individual sandy deposits in each of the elementary depositional sequences, both spatially and chronostratigraphically.