About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Journal of Sedimentary Research (SEPM)

Abstract


Journal of Sedimentary Research
Vol. 81 (2011), No. 3. (March), Pages 159-184
Research Articles: Shallow-Marine Facies Architecture

Along-Strike and Down-Dip Variations in Shallow-Marine Sequence Stratigraphic Architecture: Upper Cretaceous Star Point Sandstone, Wasatch Plateau, Central Utah, U.S.A.

Gary J. Hampson, M. Royhan Gani, Kathryn E. Sharman, Nawazish Irfan, Bryan Bracken

Abstract

The sequence stratigraphic architectures of shallow-marine deposits in the upper Cretaceous Star Point Sandstone are analyzed over a large (c. 100 km), nearly continuous outcrop section aligned oblique to depositional strike. The unit consists of five parasequences that predominantly comprise Previous HitwaveNext Hit-dominated shoreface–shelf deposits. Two parasequences contain riverdominated delta-front deposits locally. Within each parasequence, Previous HitwaveNext Hit-dominated shoreface–shelf deposits record 7–45 km of ESE- to ENE-directed progradation of a linear to moderately lobate shoreline that was supplied with sediment by longshore drift and subjected to strong offshore sediment transport by storms. Previous HitWaveNext Hit-dominated shoreface sandstones in each parasequence thin and wedge out over short distances (< 500 m) at their updip pinchouts. Lower-shoreface sandstones in each parasequence split down dip into multiple, vertically stacked, upward-coarsening bedsets separated by tongues of offshore mudstones in distal locations associated with rapid deepening of antecedent paleobathymetry. River-dominated delta-front deposits define progradation of strongly lobate shorelines in an overall direction oriented subparallel to the regional shoreline trend and into locations sheltered from Previous HitwaveNext Hit energy. These progradation directions are consistent with deflection of the deltas by Previous HitwaveTop-driven longshore currents.

The arrangement of parasequences in the Star Point Sandstone defines an overall concave-landward shoreline trajectory, with decreasing progradation and increasing aggradation through time. Along-strike variations in this trajectory pattern reflect increased tectonic subsidence towards the north combined with highly localized, large-volume, fluvial sediment supply near the northwestern limit of the study area during deposition of an areally extensive (> 800 km2) river-dominated delta-front complex (Panther Tongue). This highly focused fluvial sediment flux probably occurred via a structurally controlled sediment entry point between two active thrusts.


Pay-Per-View Purchase Options

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

Watermarked PDF Document: $14
Open PDF Document: $24