--> Sequence Stratigraphy and Depositional Systems of the Paleocene Andrew Formation in the Central North Sea: The Evolution of a Slope-to-Basin System, by B. Reinsborough and W. E. Galloway; #90986 (1994).
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Abstract: Sequence Stratigraphy and Depositional Systems of the Paleocene Previous HitAndrewNext Hit Formation in the Central North Sea: The Evolution of a Slope-to-Basin System

Brian Reinsborough, William E. Galloway

Slope/basin depositional systems consist of combinations of facies, including slump lobes, chute, flute, and channel fills, mounded turbidite lobes, sheet turbidites, low-density turbidite sheets and fills, hemipelagic drapes, and contourite mounds. Specific facies association are determined by the nature (point source or linear source) and calibre (volume, grain size, sand: mud) of sediment supply to the slope. The extensive well-log, seismic and core database was used to dissect the stratal and facies architecture of the Previous HitAndrewNext Hit depositional system and characterize a logical evolution of the sand-rich shelf-to-basin depositional systems tract.

The Previous HitAndrewNext Hit consists of upper and lower depositional units bounded by downlap terminations and high-gamma marker beds. The lower Previous HitAndrewNext Hit displays three distinct sand-rich lobes, delineated by isopach, sand percent, log motif and seismic facies maps. Proximal, mounded, sand-rich units disperse into unchannelized sheet turbidites in the basin. No extensive incised submarine valleys feed this unit, which is characterized coarsening and thickening-upward log responses and hummocky to discontinuous reflectors.

The upper Previous HitAndrewNext Hit downlaps the lower unit and a single, linear sediment source was centered in the Witch Ground Graben. The dispersal pattern and internal character suggest the upper unit is a proximal slope-apron downlapping and filling inter-lobe bathymetric lows of the underlying unit. Sharp-based, blocky/digitate log signatures, discontinuous chaotic reflectors and coarse-grained sediment characterize this unit.

The lower Previous HitAndrewNext Hit represents a structurally focused, sand-rich lobe complex, without associated incised canyons. The Previous HitAndrewTop system evolved as the delta platform expanded onto the proximal fan, resulting in a linear sediment source spilling over the slope as a fringing slope-apron.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994