Key words: Sutieng Ho pockmark Sutieng Ho gas chimney seismic Sutieng Ho polygonal fault Sutieng Ho methane authigenic carbonate Sutieng Ho Lower Congo Basin Angola

Interactions between linear chimneys, pockmarks and polygonal fault systems


            Fluid venting structures are the expression of hydrocarbon leakage or other type of fluid expulsion in sub-surface marine sediments.

            Hydrocarbon venting structures are often associated with faults and fractures which provide pathways for fluid migration through the subsurface (Ligtenberg, 2005). The expression of fluid flow structures have been observed on seismic refection data for the last three decades and have become an object of interest in marine geology. Much scientific research has focused on the relationship between faults and fractures and fluid venting structures. However, the interactions between fluid venting structures and strata-bound arrays of compaction-related normal faults (discovered by Henriet et al., 1982) known as “polygonal faults” (Cartwright and Lonergan, 1996) have only been studied closely in the last decade and remain poorly understood.

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A linear plan-form chimney associates with an overlying, linear positive high amplitude anomaly which is aligning and paralleling to it (see in 3D view).
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Anisotropic polygonal faults aligning with the circular edges of a salt-related syncline. Notice that these concentric polygonal faults are also surrounding pockmarks and have been previously show in published seismic data in Stewart et al. (2006), and briefly documented by Chopra & Marfurt (2007); Cullen et al. (2008), and described by Imbert et al. (2011); Cartwright (2011).

            In this research, I document several types of new fluid venting structures Offshore Angola that associated with polygonal faults. In particular, this work attempts to explain mechanisms by which fluid venting structures form and establish their link with polygonal faults.


You can use the links below to access my published research.