The impact of Early Cretaceous gateway evolution on ocean circulation and organic carbon burial in the emerging South Atlantic and Southern Ocean basins

Footprints of palaeocurrents in sedimentary sequences of the Cenozoic across the Maurice Ewing Bank

“…4, CDPs 12,000-13,000), to the west and southwest of the MEB hint at a shallow-intermediate (Upper Pacific Water) northward-flowing current. This complies with an opening of the Drake Passage for shallow water mass exchange between the Pacific and the South Atlantic in the Albian as suggested by Sewall et al (2007) and Dummann et al (2020). The F/MP would have played a barricading role between the Southern Ocean and the South Atlantic, except for shallowintermediate circulation at least until the late Cretaceous.…”

“…3) for the southernmost part of the Argentine and Cape basins (north of the present F/MP-MEB), within the early stage of opening of the South Atlantic (≈Aptian). Their simulation accounts for a post-Albian deep connection between the Southern Ocean and the southern South Atlantic across the Georgia Basin, confirmed by Nd isotope studies (Dummann et al, 2020). The detachment of the MEB from Africa at about the Albian may have favored the development of a deep seaway and exchange of deeper water masses (König and Jokat, 2010;Martin et al, 1982).…”

“…Following a marine transgression, deposition took place in the middle to late Jurassic in an open shelf environment. Sapropelic claystone of the late Jurassic (mainly Oxfordian) through the Aptian gives evidence for the development under euxinic conditions in a restricted basin subject to sluggish oceanic circulations (Dummann et al, 2020;Shipboard Scientific Party, 1977). Rapid subsidence gave way to open marine conditions starting in Albian and going on through the late Cretaceous and Paleocene (Barker, 1977;Ludwig, 1983;Shipboard Scientific Party, 1974a, 1974d, 1980aThompson, 1977).…”

“…Rapid subsidence gave way to open marine conditions starting in Albian and going on through the late Cretaceous and Paleocene (Barker, 1977;Ludwig, 1983;Shipboard Scientific Party, 1974a, 1974d, 1980aThompson, 1977). This transition may have resulted from abyssal connections between the Indian and the developing South Atlantic oceans (Barker, 1977;Dingle and Robson, 1992;Dummann et al, 2020;Ludwig, 1983;Shipboard Scientific Party, 1974a, 1974d, 1980a.…”

High‐Resolution C‐Isotope, TOC and Biostratigraphic Records of OAE 1a (Aptian) From an Expanded Hemipelagic Cored Succession, Western Tethys: A New Stratigraphic Reference for Global Correlation and Paleoenvironmental Reconstruction

“…The Cau core records the C9 (positive shift, Ap12a in this study) and C10 (stable values, Ap12b–Ap14 herein, Figure 2) segments, as well as the subdivisions Ap12–Ap14 (Bottini et al., 2015; Herrle et al., 2004). Segments C9–C10 have been recognized worldwide: in the Tethys (Vocontian Basin, Herrle et al., 2004; Piobbico core, Bottini et al., 2015); Central Atlantic (Mazagan Plateau, Herrle et al., 2004); Mexico (Bralower et al., 1999); and recently in the Southern Ocean (Site 511, Falkland Plateau, Dummann et al., 2020), supporting a global correlation for this upper part of the Aptian C‐isotope stratigraphy.…”