Sedimentologic, stratigraphic, and structural evolution of minibasins and a megaflap formed during passive salt diapirism: The Neoproterozoic Witchelina diapir, Willouran Ranges, South Australia

摘要: Abstract This study documents the growth of a megaflap along flank passive salt diapir as result long-lived interaction between sedimentation and halokinetic deformation. Megaflaps are nearly vertical to overturned, deep minibasin stratal panels that extend multiple kilometers up steep flanks diapirs or equivalent welds. Recent interest has been sparked by well penetrations unidentified megaflaps typically in economic failure, but their formation is also fundamental understanding early history basins. represents one first systematic characterizations an exposed with regards sub-seismic sedimentologic, stratigraphic, structural details. The Witchelina Neoproterozoic primary eastern Willouran Ranges South Australia. Flanking strata Top Mount Sandstone, Willawalpa Formation, Quartzite, oblique cross section, record diapirism Trough, including halokinetically drape-folded megaflap. offers unique opportunity investigate sedimentologic responses initiation evolution movement. Using field mapping, stratigraphic sections, petrographic analyses, correlation diagrams, quantitative restoration, we document depositional facies, thickness trends, geometries interpret environments, sequence stratigraphy, flanking minibasins. Mount, Willawalpa, were deposited barrier-bar-complex tidal-flat temporal spatial variations patterns strongly influenced from earliest stages passively rising on both regional (basinwide) local scales. salt-margin geometry was depositionally modified erosional boundary formed shoulder, above which eventually became subsequently deposited. shift margin progressive migration depocenter began rotation into geometry, documenting new concept deposition deformation during