Evolution and morphology of a contourite depositional system based on new evidence from 3D-seismic data offshore Madagascar (Paleogene, Morondava Basin).

Numerous bottom current-controlled depositional and erosional features, which together form Contourite Depositional Systems (CDS), have been recognized in deep-water settings over the past decade. Most of these systems are described based on two-dimensional (2D) seismic data, whereas only a few CDS have been characterised from high-resolution 3D data. Here we document a newly identified CDS that formed during the Paleocene within the Morondava Basin, offshore west Madagascar, through analysis of a depth-migrated 3D seismic survey, enhanced by the implementation of seismic attributes.

Lateral migration of large sedimentary bodies in a deep-marine system offshore of Argentina.

Contourite features are increasingly identified in seismic data, but the mechanisms controlling their evolution remain poorly understood. Using 2D multichannel reflection seismic and well data, this study describes large Oligocene- to middle Miocene-aged sedimentary bodies that show prominent lateral migration along the base of the Argentine slope. These form part of a contourite depositional system with four morphological elements: a plastered drift, a contourite channel, an asymmetric mounded drift, and an erosive surface.

Isolation of the South China Sea from the North Pacific Subtropical Gyre since the latest Miocene due to formation of the Luzon Strait.

The North Pacific subtropical gyre (NPSG) plays a major role in present global ocean circulation. At times, the gyre has coursed through the South China Sea, but its role in the evolutionary development of that Sea remains uncertain. This work systematically describes a major shift in NPSG paleo-circulation evident from sedimentary features observed in seismic and bathymetric data.

Mediterranean isolation preconditioning the Earth System for late Miocene climate cooling.

A global Neogene cooling trend culminated ~7 million years ago with the onset of Greenland glaciation. Increased ocean-atmosphere interaction and low- to high-latitude circulation are thought to be key factors in reorganizing late Miocene global temperature and precipitation patterns, but the drivers of this reorganization have yet to be identified. Here, we present new information about the evolution of the Atlantic-Mediterranean gateway that generated Mediterranean overflow.