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Integrated analysis of high-quality three-dimensional (3D) seismic, seabed geochemistry, and satellite-based surface slick data from the deep-water Kwanza Basin documents the widespread occurrence of past and present fluid flow associated with dewatering processes and hydrocarbon migration. Seismic scale fluid flow phenomena are defined by seep-related seafloor features including pockmarks, mud or asphalt volcanoes, gas hydrate pingoes, as well as shallow subsurface features such as palaeo-pockmarks, direct hydrocarbon indicators (DHIs), pipes and bottomsimulating reflections (BSRs). BSR-derived shallow geothermal gradients show elevated temperatures attributed to fluid advection along inclined stratigraphic carrier beds around salt structures in addition to elevated shallow thermal anomalies above highly conductive salt bodies. Seabed evidences of migrated thermogenic hydrocarbons and surface slicks are used to differentiate thermogenic hydrocarbon migration from fluid flow processes such as dewatering and biogenic gas migration. The analysis constrains the fluid plumbing system defined by the three-dimensional distribution of stratigraphic carriers and seal bypass systems through time. Detailed integration and iterative interpretation have confirmed the presence of mature source rock and effective migration pathways with significant implications for petroleum prospectivity in the post-salt interval. Integration of seismic, seabed geochemistry and satellite data represents a robust method to document and interpret fluid flow phenomena along continental margins, and highlights the importance of integrated fluid flow studies with regard to petroleum exploration, submarine geohazards, marine ecosystems and climate change.

Recent exploration activity in the Austral-Magallanes Basin revealed the presence of sand injection complexes of Upper Cretaceous–Paleocene age. The discovery of these large-scale sandstone intrusions documents the first onshore example of sand injection complexes as hydrocarbon exploration targets and confirms a more widespread phenomenon than previously known. Integration of regional understanding, three-dimensional seismic reflection data, exploration wells, and whole core have allowed the interpretation of large sand injectites associated with a deep-water depositional system in the Austral-Magallanes Basin. These injectites are characterized seismically by circular to elongate amplitude anomalies with cross-cutting and discordant stratigraphic relationships. Additionally, detailed sedimentological analysis from exploration wells and core confirm the presence of facies consistent with injected sand commonly associated with deep-water depositional systems. The presence of giant sand injection complexes in the Austral-Magallanes Basin records a previously undocumented period of pore-fluid overpressure that led to large-scale hydraulic fracturing of the overburden and subsequent fluidization of sand derived from a deep-water depositional system. The discovery of intrusive traps such as sand injection complexes defines a new play with significant exploration potential; however, additional evaluation is required to understand the nature and degree of primary sandbody geometrical modification and the subsequent impact on reservoir distribution, trap geometry, migration pathways and seals.

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