The sedimentological expression of transgression–regression cycles upon aeolian–marine margins

Abstract

When compared to their temperate coastal counterparts, sediments deposited and preserved along arid aeolian to shallow‐marine margins remain relatively poorly understood, particularly at the scale of lithofacies units and architectural elements. These systems often record evidence for relative sea‐level change within sedimentary basins. This work focusses on the Entrada–Curtis–Summerville formations that crop out in central eastern Utah, USA, and provides a detailed analysis of the aeolian Moab Member of the Curtis Formation (informally known as the Moab Tongue) that was impacted by cycles of marine transgressions and regression in the late Jurassic. This study utilises photogrammetry, sedimentary logging and sequence‐stratigraphical analysis techniques. Results indicate that four short‐lived transgressive‐regressive cycles are preserved within the Moab Member, followed by a broad regressive event recorded at the transition between the Curtis and Summerville formations. These cycles relate to changes in the relative sea level of the Sundance Sea and the deflation and expansion of the neighbouring aeolian dune field. During periods of normal regression, marine sediments displayed evidence of tidal and wave action, whereas the continental domain was characterised by growth of the aeolian system. However, when regression occurred within optimal physiographic conditions such as a restricted, semi‐enclosed basin, and at sufficient magnitude to outpace erg expansion, this acted to shut‐down bedform development and preservation. A rapid restriction of aeolian sediment availability and the inability of the dune field to recover resulted in the formation of deflationary sandsheets, arid coastal plain strata and contemporaneous shallow‐marine deposits that are starved of wind‐sourced sediments. This study highlights how a rapidly developing high‐magnitude regression can lead to the overall retraction of the erg. Deciphering the evolution and sequence stratigraphical relationships of arid aeolian to shallow marine margins is important in both understanding environmental interactions and improving the characterisation of reservoir rocks deposited in these settings.

Correlations between Petroleum Reservoir Fluid Properties and Amount of Evolved and Dissolved Natural Gas: Case Study of Transgressive–Regressive-Sequence Sedimentary Rocks

“…The repeated cycles of dolostone with thin layers of anhydrite and claystone probably indicate a shallowing upward condition during the deposition of the Jeribe Formation (Figure 2). This cycling could be related to changes in the sea level during the depositional setting [21]. Furthermore, the entire Lower Miocene is absent in the west, over the Ga'ara high; however, the Euphrates limestone and Jeribe Formation are close to exposure to the Euphrates River, far beyond the occurrence of the Oligocene deposits, thus stressing the importance of the basal Miocene transgression, which could be strongly linked to major transgressive-regressive cycling between the Jeribe and Lower Fars formations.…”

Mixed depositional processes in coastal to shelf environments: Towards acknowledging their complexity

“…Cross et al (2023) investigate the Jurassic aeolian‐marine Curtis‐Summerville sedimentary successions of central Utah (USA) and focussed on the nature of the aeolian stratigraphic record. The authors assessed relationships between aeolian and marine sub‐environments, which were influenced by repeated transgression (T) and regression (R) periods.…”

“…Overall, these outcrop-based insights provide the foundation for an onshore-to-offshore stratigraphic model extending into the unexplored frontier basin surrounding South-East Sulawesi. Cross et al (2023) investigate the Jurassic aeolianmarine Curtis-Summerville sedimentary successions of central Utah (USA) and focussed on the nature of the aeolian stratigraphic record. The authors assessed relationships between aeolian and marine sub-environments, which were influenced by repeated transgression (T) and regression (R) periods.…”