South Atlantic paleobathymetry since early Cretaceous

Area of Science:

• Paleoceanography
• Paleoclimate Reconstruction
• South Atlantic Oceanography

Background:

• Early ocean circulation was influenced by restricted topography and salinity.
• Seafloor spreading and gateway openings significantly altered oceanic pathways.
• Understanding past ocean dynamics is crucial for interpreting climate and biogeographic shifts.

Purpose of the Study:

• To provide paleobathymetric reconstructions for the South Atlantic from the Early Cretaceous to the present.
• To offer quantitative uncertainty estimates for these reconstructions.
• To establish a foundation for studying paleocirculation, paleoclimate, and paleobiogeography.

Main Methods:

• Paleobathymetric reconstruction techniques.
• Quantitative uncertainty estimation methods.
• Analysis of geological and tectonic data for the South Atlantic.

Main Results:

• Initial circulation favored evaporite deposition due to restricted topography.
• An equatorial gateway opening facilitated shallow and intermediate circulation.
• Deepening and widening of the South Atlantic, along with Drake Passage opening, established modern thermohaline circulation by the mid-Miocene.

Conclusions:

• Oceanographic gateways and tectonic subsidence played critical roles in Late Cretaceous climate change.
• The evolution of South Atlantic gateways profoundly impacted global ocean circulation patterns.
• Paleobathymetric reconstructions provide essential data for understanding long-term ocean-climate-biogeography interactions.