Fine Structure Interpretation And Target Evaluation Of He-3 Member In The North Of Jinglou Oilfield Of Biyang Depression

Biyang Depression is a Meso-Cenozoic continental dustpan-like fault-basin. According to structural characteristics, the depression can be divided into three belts from south to north: south steep slope, middle deep slope and north gentle slope. Sedimentary cover is mainly Cenozoic with max thickness of 8000 meters. The research lies in west slope belt mainly including Gucheng nose structure and Jinglou anticline. The main research target interval is He-3 member of Hetaoyuan formation.The formation and development of Biyang Depression experienced multistage tectonic movements; fault system is complicated with many fault noses and blocks. On this background, favorable structural bands showed the complexity. Meanwhile, because single reservoir thickness is very thin and the lateral variety of reservoir is fast, the research of the reservoir distribution is very difficult.Firstly, under the guide of Exploration Seismology and Structural Geology, using a series of fine structure interpretation techniques: automatic tracking, horizontal slice, coherence cube, after detailedly studying logging, drilling and seismic data, we made horizon tracing and fault interpretation for 80km2 three dimensional seismic data and drawn eight structural maps of H3â…¢top, H3â…£top, H3â…¤top, H3â…¥top, H3â…¦top, H3â…§top, FH bottom and H3â…£7 top. On the basis, fault profile and plane characteristics have been studied and the research area was divided into five secondary structural belts: the south structural belt, the middle structural belt, the middle strike-slip structural belt, the west unconformity trap belt and the north unconformity trap belt.Secondly, under the guide of Reservoir Geology, Sequence Stratigraphy and Seismic Sedimentology, using seismic attributes, we made the reservoir distribution, sedimentary micro-facies research and drawn sedimentary micro-facies maps, sand body thickness maps and physical property characteristic maps for H3â…£7 and H3â…£9 oil thin layers. The favorable reservoir distribution areas have been predicted and the local structural control effect for sedimentary micro-facies has been analyzed.Finally, on the basis of structure and reservoir research, according to the configuration relations and oil accumulation characteristics, trap evaluation and description has been made using logging, coring, oil testing, and production test data. It is considered thatâ…¡faults in east-north direction control the distribution of secondary structural belts; thatâ…¡faults uplifted side are favorable oil enrichment areas; strike-slip faults destroyed early stage oil reservoir and formed secondary oil reservoir locally.