Highlights—Change on the Delta

Stratigraphy represents the cumulative record of a suite of processes.  To understand to nature and origin of the sediment and geometries of a delta systems, Salahuddin and Lambiase examine relationships among hydrodynamics, facies distribution, sand body geometry, stratigraphic succession and morphology on the Holocene Mahakam Delta.  Although this delta has been interpreted previously as a progradational, mixed fluvial and tidal system, their results suggest a discordant relationship – depositional facies more closely reflect present-day processes that are “overprinting” relict delta morphology.  The relationships of several generations of delta processes during transgression can form important input for prediction of subsurface reservoir geometries and properties.  They similarly suggest that results imply that models derived from modern deltas require quantitative hydrodynamic analysis to be accurate, and that transgressive deltaic deposits may occur more commonly than currently recognized.

Sediment dynamics and depositionalsystems of the Mahakam Delta, Indonesia: ongoing delta abandonment on atide-dominated coast by Salahuddin and Joseph J. Lambiase