Coupled 'storm-flood' depositional model: Application to the Miocene-Modern Baram Delta Province, north-west Borneo

Daniel S. Collins, Howard D. Johnson, Peter A. Allison, Pierre Guilpain, Abdul Razak Damit, Mariano Marzo
2017 Sedimentology  
11 The Miocene to Modern Baram Delta Province (BDP) is a highly efficient source-to-sink 12 system that has accumulated 9-12 km of coastal-deltaic to shelf sediments over the past 15 13 Myr. Facies analysis based on ca 1 km of outcrop, combined with subsurface geology and 14 sedimentary processes in the present-day BDP, suggests a 'storm-flood' depositional model 15 comprising two distinct periods: (1) fairweather periods are dominated by alongshore 16 sediment reworking and coastal sand
more » ... ation; (2) monsoon-driven storm periods are 17 characterised by increased wave energy and offshore-directed downwelling storm flow that 18 occur simultaneously with peak fluvial discharge caused by storm-precipitation ('storm-19 floods'). The modern equivalent environment has the following characteristics: (1) humid-20 tropical monsoonal climate; (2) narrow (ca < 100 km) and steep (ca 12°), densely vegetated, 21 coastal plain; (3) deep tropical weathering of a mudstone-dominated hinterland; (4) multiple 22 independent, small-to moderate-sized (10 2 -10 5 km 2 ) drainage basins; (5) predominance of 23 river-mouth bypassing; and (6) supply-dominated shelf. The ancient, proximal part of this 24
doi:10.1111/sed.12316 fatcat:ee7oaz7dtvbznnuz7zo2exz5bq