Quaternary Contourites of the Northern Argentine Continental Margin and their Relationship with Subsurface Hydrocarbon Exploration

PRINCIPI, SEBASTIÁN; ACOSTA, LUANA; PALMA, FERMÍN; ORMAZABAL, JUAN PABLO; ISOLA, JOSÉ IGNACIO; TASSONE, ALEJANDRO ALBERTO

Montevideo

Conferencia; First EAGE Conference on South Atlantic Offshore Energy Resources; 2023

European Association of Geoscientists & Engineers

The Northern Argentine Continental Margin (NACM) is part of the South American passive volcanic rifted margin that stretches from southern Brazil to northern Patagonia and is the host of the Colorado sedimentary offshore basin (Figure 1). This work focuses on the most recent sedimentary deposits of the basin, that form a large contourite depositional system (CDS) along the continental slope (Hernández-Molina et al., 2009; Ercilla et al., 2019; Gruetzner et al., 2016). The formation of this CDS is attributed to the northward flow of modern deep-water masses, including the Antarctic Intermediate Water (AAIW), the Upper Circumpolar Deep Water (UCDW), the Lower Circumpolar Deep Water (LCDW), and the Antarctic Bottom Deep Water (AABW), which have produced both erosive and depositional features (Hernández-Molina et al., 2009; Preu et al., 2013; Violante et al., 2010).In the framework of the "Pampa Azul Initiative”, a national program aimed at promoting ocean science research in Argentina, a bathymetric dataset covering an area of 13000 km2 was obtained during the YTEC-GTGM 4 cruise in 2019 aboard the R/V Austral. Six sediment cores were obtained during the same survey.In this work, we analyze the bathymetric and sediment data in conjunction with multichannel 2D seismics to characterize the lower slope contourites that shape the modern seafloor, as well as the underlying fault system that disrupt most of the sedimentary column. By studying the geological processes that drive the formation of the CDS as well as the subsurface structural features, we hope to gain insights into the dynamics of the NACM and the identification of possible seepage systems in the region.