Sedimentology and stratigraphic architecture of a fluvial to shallow-marine succession: The Jurassic Dhruma Formation, Saudi Arabia

ABSTRACT The interaction of fluvial, tidal, and wave processes in coastal paralic environments gives rise to sedimentary successions with highly varied styles facies architecture; these are determined by the morphology evolutionary behavior range sub-environments, which may be difficult diagnose subsurface limited well control. This study presents depositional models account for stratigraphic complexity a fluvial shallow-marine succession, Middle Jurassic Dhruma Formation, Saudi Arabia. achieves following: i) it examines demonstrates relationships between various nearshore, deposits, ii) develops inherent successions, iii) documents sedimentology patterns lower Formation studied area dataset comprises descriptions 570 m core from 14 wells, 77 representative thin sections, gamma-ray logs, FMI image logs 4 wells. These data integrated quantitative information > 50 analogous systems wide modern ancient settings, stored relational database. Stratigraphic correlations reveal internal anatomy succession. Facies associations channels, intertidal flats, pedogenically modified supratidal flats or floodplains, river-influenced tidal bars, weakly storm-affected shoreface offshore-transition zones, storm-dominated delta-front prodelta an open-marine carbonate-dominated shelf. sub-environments interacted complex way through space time. vertical succession interval records overall transition coastal-plain deposits at base marine top. As such, long-term transgressive, deepening-upward trend. However, this general trend is punctuated repeated progradational events whereby sand bodies wave, origin prograded basinward during stillstands fill bays along coastline. nature juxtaposition neighboring has resulted record that compared generated morphologically simple accumulate more regularly ordered stratal packages.