Sediment and soil source apportionment using geochemical fingerprinting techniques in the Winam Gulf, Lake Victoria

CATENA, Год журнала: 2025, Номер 255, С. 109053 - 109053

Опубликована: Апрель 18, 2025

Язык: Английский

Mixed Sedimentation in the Transition Zone Between a Shallow-Water Delta and Tidal Flat and Its Influence on Reservoir Quality: A Case Study of Member B of the Asmari Formation in C Oilfield, South Iraq

Applied Sciences, Год журнала: 2025, Номер 15(9), С. 5084 - 5084

Опубликована: Май 3, 2025

The transition zone between a shallow-water delta and tidal flat is characterized by high degree of mixed siliciclastic–carbonate sedimentation. There are frequent lateral vertical variations in sandstone, dolostone, limestone, rock (MSR); however, their influence on reservoir quality remains uncertain. Member B the Asmari Formation (Asmari B) Iraq’s C Oilfield was deposited remnant ocean basin formed closure Neo-Tethys Ocean. During Oligocene–Miocene, exposure Arabian Shield provided intermittent sediment sources to study area. Under shallow water relatively arid conditions, widespread sedimentation siliciclastic sand dolomitic components occurred. Taking as case study, this research employs core thin-section observations, trace element analyses, quantitative mineralogical interpretations logging data investigate characteristics evaluate its impact quality. Four key aspects were identified: (1) main types lithofacies developed Formation, namely sandstone-bearing dolomite, dolostone-bearing sand, sandy dolostone. These distributary channels intertidal with different depths. As terrigenous input decreased, depth for sand-bearing facies increased. In particular, dolostone predominantly subtidal settings under storm events. (2) MSRs categorized based proportion minor component into low mixing degrees. Based mineral compositions interpreted from well data, thickness ratio, using high- low-mixing-degree relative total formation. mainly B1, B2, B3-1, B3-2, B4 sublayers, where moderate provenance supply facilitated clastic carbonate components. (3) pore throat patterns MSR reservoirs change index. When dolomite content sandstone exceeds 25%, pore–throat structure changes significantly. A small amount has little effect throat. Sandy exhibits poorest (4) Mixed distributed both sides mouth bar. flat. thin isolated due This provides guidance understanding development similar geological settings, facilitating next step oil gas exploration these special reservoirs.

Язык: Английский

Tracking the multiple sources of sediment within an agricultural catchment in Northeast China

CATENA, Год журнала: 2025, Номер 257, С. 109143 - 109143

Опубликована: Май 17, 2025

Язык: Английский