Analysis of the genesis model of large-scale mixed tidal flats in F oilfield

YANG Lina, ZHANG Xuemin, WEI Li, SHI Changlin

Mixed tidal flat, Sedimentary characteristics, Causal mode, Asmari Group

The F oilfield has developed a set of large-scale mixed tidal flat sediments in the transitional phase between sea and land, with diverse mixed deposition forms. In order to better understand the distribution pattern of mixed reservoirs in F oilfield, improve the production of the oilfield, and enrich the relevant theories of mixed tidal flats, a large-scale study on the genesis model of mixed tidal flats has been carried out. By comprehensively utilizing core, logging, and seismic data, and based on the identification of sedimentary microfacies, the mixed deposition form and distribution characteristics of mixed tidal flats are studied; Based on the analysis of various geological elements, three connected land platform models with mixed tidal flats were established to explain the genesis of the large mixed tidal flats in the F oilfield. The research results indicate that although the three modes have different facies zones, they share common characteristics, namely, the climate in the exposed areas on land is arid, and salt marsh gypsum and evaporite dolomite are widely developed; There are terrestrial debris in the nearshore zone, and based on the abundance or scarcity of terrestrial debris material and whether the environment is clean and warm, the nearshore zone is divided into two different environments: detrital tidal flat sedimentary environment and carbonate tidal flat sedimentary environment; The high-energy shallow water barrier beach (island) on the edge or surface of the continental shelf causes the confined seawater behind it to form a lagoon, leading to large-scale mixed tidal flat sedimentation. These common features of the three modes are necessary conditions for the formation of a large mixed tidal flat in the F oilfield.

https://dx.doi.org/10.31873/IJEAS.12.09.01