REGIONAL SEQUENCE STRATIGRAPHIC SETTING OF THE MISSISSIPPI FAN COMPLEX, NORTHERN DEEP GULF OF MEXICO: IMPLICATIONS FOR EVOLUTION OF THE NORTHERN GULF BASIN MARGIN
Published:December 01, 1994
Paul Weimer, Barrett T. Dixon, 1994. "REGIONAL SEQUENCE STRATIGRAPHIC SETTING OF THE MISSISSIPPI FAN COMPLEX, NORTHERN DEEP GULF OF MEXICO: IMPLICATIONS FOR EVOLUTION OF THE NORTHERN GULF BASIN MARGIN", Submarine Fans and Turbidite Systems—Sequence Stratigraphy, Reservoir Architecture and Production Characteristics Gulf of Mexico and International, Paul Weimer, Arnold H. Bouma, Bob F. Perkins
Download citation file:
The Mississippi Fan Complex is a large submarine fan unit in the deep northern Gulf of Mexico. This complex comprises two distinct submarine fans: the Western and Eastern Fan. Regional mapping of the continental slope and deep basin have further refined the interpretation for the evolution of this area in the Gulf of Mexico. The Western Fan consists of seventeen depositional sequences that were deposited during the late Miocene (5.5 Ma) to the Present. At least seven discrete submarine canyons located in the Ewing Bank, Green Canyon, and Mississippi Canyon lease areas can be traced downslope to their terminus in the equivalent channel-levee systems. The Eastern Fan consists of eight depositional sequences that are coeval to sequences 8-11, 13-16 in the Western Fan. The submarine canyons that fed diese channel-levee systems are located immediately due east of the modem Mississippi bird-foot delta.
Internally, the depositional sequences of the Western and Eastern Fans had similar stratigraphie evolution. Erosional surfaces (sequence boundaries) are at the base of most sequences in the Western Fan amd are overlain by mass transport complexes. In the Eastern Fan, there is generally less erosion at die base of die sequences and mass transport complexes arc generally absent. Channel-levee systems comprise the bulk of the sediments in both fans and can be mapped in both fans. However, the channels in die Eastern Fan are considerably smaller in dimensions than the Western Fan; the eastern channels also have less lateral migration, less sinuosity, and fewer downfan avulsion of channels than the coeval channels in die Western Fan. Large portions of diree sequences in die Eastern Fan consist of in situ slides.
The correlation of die coeval fan sequences between the Eastern and Western Fans lends further evidence of the eustatic control on die timing of these depositional sequences. Compilation of regional work from the slope and shelf areas has also led to the refinement of the age dates of the Mississippi Fan Complex sequences. Sequences 14-17 are now recognized to be 70,000 years to the Present. Sequences 6-13 are interpreted to be 1.9 to 0.40 Ma. Sequences 1-5 are interpreted to be 5.5 to 3.0 Ma. Two major stacked condensed sections are present in the fan: 3.0 to 1.9 Ma, and 0.4 to 0.07 Ma. The development of die condensed sections reflects major avulsions and shifts in the position of the feeding deltaic systems on the continental shelf.