About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

GCAGS Transactions

Abstract


Gulf Coast Association of Geological Societies Transactions
Vol. 49 (1999), Pages 404-411

Dynamic Response of Deepwater Depositional Systems to Growth of the Mississippi Fan Fold Belt, Gulf of Mexico

Ciaran J. O'Byrne (1), Joydeep K. Haldar1, Richard Klecker (1), Arthur E. Berman (2) and John Martinez (1)

(1) BP-Amoco Exploration, Houston, TX 77079

(2) 623 Lorfing Lane, Sugarland, TX 77479

ABSTRACT

Acquisition of high quality 3-D data volumes in Atwater Valley, Gulf of Mexico (Fig. 1), coupled with proprietary 3-D Previous HitcoherencyTop visualization has allowed for exceptional clarity in imaging map view realizations of Miocene and Pliocene depositional systems in the Mississippi Fan Fold Belt (MFFB) at one to four seconds below mudline. Regional studies and 'loop' level analyses of deepwater seismic facies geometries in this area indicate a near fractal response of depositional systems to sea floor gradient change in time and space.

The structural evolution of the MFFB caused critical slope changes through Mio-Pliocene time that effected both regional and local drainage patterns in pre-, syn-, and post-growth strata. Depositional topography related to variable rates of sediment accumulation also played a key role in influencing slope sediment pathways, drainage capture and compensatory relief. Growth of the MFFB effectively created elevated 'plateau' areas deflecting sediment pathways which bypassed their flanks. Differential growth rates within this portion of the fold belt resulted in an overall west to east gradient, with younger more elevated structures developed in the west. This topography was later encroached on and ultimately enveloped by Plio-Pleistocene slope progradation. Pliocene drainage capture within the MFFB is evidenced by east-west trending erosional valleys and channel meander belts sourced from evolving dip fed canyon systems to the west and directed eastwards for up to 40 miles along strike prior to exiting onto the abyssal plain.

Up-dip of the MFFB, Mio-Pliocene depositional rates periodically overwhelmed salt topography creating a bypass or smoothed slope profile (Prather et al, 1998), with relatively linear erosional valley systems, locally affected by salt structures. Geometric aspects of a wide variety of channel and sheet architectural elements defining mud-prone or heterolithic constructional and sand prone ponded seismic facies are discussed within the tectono-stratigraphic framework of the MFFB with implications for reservoir and seal distribution in the area.


Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24