The northeastern extension of the Sigsbee Scarp can be traced from 27°10′N, 90°10′W to 28°50′N, 88°05′W across the Mississippi Cone. About 60 km of the Sigsbee Scarp is buried beneath the Mississippi Cone and was traced in the subsurface. The rest of the scarp possesses a distinct topographic expression. The northeastern extension is divided into three segments on the basis of differing topographic and structural character. The western segment (I) is the continuation of the well-developed Sigsbee Scarp west of 90°W. The central segment (II) comprises over three-fourths of the northeastern extension. Its topography and structure are concealed by the sedimentation of the Mississippi Cone. The eastern segment (III) is a transition before the scarp termination.

Segment II is most representative of the northeastern extension. The western half consists of one major scarp-forming salt ridge plus a small segment of a ridge basinward of the major ridge. The eastern half consists of two major ridges and two basinward ridges, the two major ridges being continuations of the two ridges of the western half. The ridges result from vertical salt movement caused by existing lateral pressure gradient from the loading of prograding Mississippi Cone sediments. The major ridge in the western half of segment II is the result of late Wisconsin to early Holocene formation of the cone by sediments fed through the depocenter of the Mississippi Trough. The two major ridges in the eastern half resulted from Holocene sedimentation after the depocenter shifted east to the present Mississippi delta.

A 450-sq km area of possible gas accumulation is present on the eastern part of the cone near the scarp.

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