Syn-sedimentary salt diapirism as a control on fluvial-system evolution: an example from the proximal Permian Cutler Group, SE Utah, USA

摘要: Loading of subsurface salt during accumulation fluvial strata can result in halokinesis and the growth pillows, walls diapirs. Such movement may eventually formation salt-walled mini-basins, whose style architectural infill be used to infer both relative rates salt-wall sedimentation nature fluvial-system response movement. The Salt Anticline Region Paradox Basin SE Utah comprises a series elongate saltwalled arranged NW-trending array. bulk occurred deposition Permian Cutler Group, wedge predominantly quartzo-feldspathic clastic comprising sediment derived from Uncompahgre Uplift NE. sedimentary architecture selected mini-basin fills has been determined at high resolution through outcrop study. Minibasin centres are characterized by multi-storey channel elements into stacked complexes, with only limited preservation overbank elements. At margins, thick successions sheet-like dominate rim-syncline depocentres adjacent walls; many such accumulations unconformably overlain single-storey that accumulated episodes breaching. absence gypsum clasts suggests influx was high, preventing syn-sedimentary surface exposure salt. Instead, fluvial breaching salt-generated topography reworked previously deposited sediments Cutler Group atop growing walls. Palaeocurrent data indicate palaeoflow SW early in history basin subsequently diverted theWand ultimately NW as salt walls grew form topographic barriers. Late-stage retreat system coincided with construction an aeolian system, recording period heightened climatic aridity. Aeolian preserved lees some walls, demonstrating halokinesis played complex role differential trapping sediment.