The influence of salt withdrawal subsidence on palaeosol maturity and cyclic fluvial deposition in the Upper Triassic Chinle Formation: Castle Valley, Utah

摘要: Integrated fluvial sequence stratigraphic and palaeosol analysis can be used to better reconstruct depositional systems, but these approaches have not been combined examine halokinetic minibasins. This study characterizes the temporal spatial patterns of lithofacies palaeosols in a framework model minibasin evolution identify influences on deposition. research documents cycles hierarchy, maturity apparent sediment accumulation rates Chinle Formation within Big Bend minibasin. also uses help aggradational cycle (FAC) sets. The is divided into two hectometre-scale (102 m) sequences, six decametre-scale (101 m) FAC sets, variable numbers metre-scale FACs depending proximity Ten pedotypes representing 225 profiles are recognized. include similar modern Entisols, Inceptisols, Aridisols, Vertisols Alfisols. A index (1–5) assigned each pedotype assess its variability development. Estimated development time approximate rates. Increased subsidence resulted greater number thicker FACs, sets sections, associations reflecting more rapid sedimentation along axis. Palaeocurrent indicators converge towards axis indicate that it formed drifted through time. Relative inversely related stratal thickness, decreases where episodic burial by was frequent. Metre-scale most abundant axis, locally Entisols Inceptisols developed upon their upper boundaries increased Areas outside characterized fewer associated with mature palaeosols. Palaeosol-derived as much orders magnitude than marginal areas. stratigraphic, palaeocurrent evidence develop for illustrates affect landscape processes.