--> Abstract: Deciphering Proximal/Distal from Along-Strike Variations in Submarine Channel Architecture in the Permian Middle Brushy Canyon Formation, West Texas, by Roger N. Wagerle and Michael H. Gardner; #90914(2000)

Datapages, Inc.Print this page

Roger N. Wagerle1, Michael H. Gardner2
(1) Colorado School of Mines, Golden, CO
(2) Colorado School of Mines, CO

Abstract: Deciphering proximal/distal from along-strike variations in submarine channel architecture in the Permian middle Brushy Canyon Formation, West Texas

Spatial variations in submarine channel architecture are examined by comparing changes in lithology, channel shape and size, and facies distributions within a siltstone- bounded fourth-order cycle (fan 5) in the middle Brushy Canyon Formation. Fan 5 deposits are correlated across two conduits (4.5-km apart) that obliquely intersect the outcrop in progressively more basinward positions. Clustered channel complexes and increased sand percent relative to adjacent deposits characterize each conduit.

The more proximal conduit contains deep and narrow, vertically stacked channel cuts forming more multistory complexes. Heterolithic bypass deposits containing coarse fusulinid conglomerates commonly floor channels. The bypass deposits, coarse sandstones, and increased cut frequencies occur within a thinner fan cycle showing decreased siltstone and sandstone bed lengths. The more distal conduit shows a 15% increase in deposits that precede channelization and thicken fan 5. Broad and shallow channel cuts show more offset to produce more multilateral complexes. Channel fills contain minor bypass deposits and shelf-derived carbonate allochems and more finer grained structureless and dewatered sandstones.

If increased sediment supply to the more distal fan conduit is responsible for thicker and sandier fan 5 deposits, they should also contain more shelf-derived and coarser sediments and more frequent channel cuts. Because the channel attributes are restricted to the more proximal conduit deposits, channel architecture changes across the two conduits more likely reflect proximal-distal changes. Despite significant shape changes, channel complexes in both conduits show similar aspect ratios indicating that this measure does not help resolve architectural variation between the two conduits.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana