Large-scale shallow braided river delta depositional characteristics and depositional pattern of Mungaroo Formation in Late Triassic, North Carnarvon Basin, Australia
The drilling, seismic, cores and thin section data of Mungaroo delta in North Carnarvon Basin of Australia were analyzed. Sedimentary sequence and migration evolution of shallow braided river delta in different monsoon stages were built through the sedimentary background, sedimentary features and intermittent stage of monsoon climate change, and the depositional model of Mungaroo Formation, North Carnarvon Basin was built. The results show that Mungaroo delta has five typical sedimentary characteristics: Delta plain facies is well developed and normal graded channel deposition is widespread; Channel sandstone and the mudstone rich of organic matter are interbedded frequently; Clast granules are poorly sorted and rounded but rich of quartz granule; Mungaroo Formation in late Triassic generally develops parallel-subparallel seismic facies and locally imbricate progradation reflection seismic facies; Sporopollen of alpine vegetation and lowerland plant changes interactively under the control of monsoon climate.