Paleogene-neogene Reservoir-forming Structure Combination And Its Relationship With Oil And Gas Reservoir Distribution In Jiyang Depression

Structure plays an important role in controlling the formation and distribution of oil and gas reservoirs.A lot of previous studies have been conducted on basin structure,zone structure,trap structure and other aspects,but the researches on structures closely related to oil and gas accumulation?Concave-uplift composite structure,fault-rock composite structure?are not deep enough.According to the key seismic reflection structure diagram,2D and 3D seismic data interpretation,combining with the logging,core analysis data,in Jiyang depression of T₆?Es3 bottom?,T₂?Es1 bottom?,T₁?Ng bottom?today's three bottom Concave-uplift structure and the Es3 bottom,the Es1 bottom,Ng bottom in different geological period Concave-uplift combination structure has carried on the division and correlation,analysis of the six key combination structure,fault-strata and the Concave-uplift combination strata combination structure,fault structure and studied the relationship between the study,has made the following points:?1?save-uplift composite structureBased on the configuration relationship of trough line,ridgeline and valley line,the current sag composite structures in the T₆,T₂ and T₁ seismic reflection layers of Jiyang depression are divided.The main sag composite structures are pitch-concave side uplift,pitch-concave side uplift and ring-concave middle uplift,among which the sag and side uplift composite structures have the largest number.Will T₆ reflected the current concave combination structure and Es3 bottom in Ed sedimentary final,Ng sedimentary final,Nm sedimentary final Concave-uplift combination of the final structure comparison,the results show that T₆ layer combination concave lung structure and sand three bottom today in Ed sedimentary final,Ng sedimentary final,Nm sedimentary final Concave-uplift combination structure is broadly in line with a partition.?2?fault-rock composite structureThe fault-rock combination structures of six key faults in Zhanhua sag,including no.1fault,No.2 fault and Gubei fault,were analyzed from six aspects,including fault-rock plane combination,fault-break horizon,fault-fault cross section structure,fault-rock occurrence combination,activity and fault-crack maintenance.Among them,No.1 fault is a downslope fault,which breaks to the surface.The occurrence combination of the fault and rock layers on both sides is a ridge combination from bottom to top and a synclinal half-ridge and half-valley combination.No.3 fault is a shear slope fault,which is cut to the surface.The occurrence combination of the fault and the strata on both sides is a synclinal half-ridged and half-valley combination.?3?the relationship between save-uplift composite structure and discovered oil and gas reservoirsIn the strata of Es4 and Es3 developed in source rocks,the sandstone oil and gas reservoirs of Es3 and Es4 are closely related to the Concave-uplift composite structure.Oil and gas reservoirs in the Es4 and Es3 sections are distributed in the saddle,around the ridge line,high part of the valley line,slope between the ridge line and the valley line,and near the uplift line.Few oil and gas reservoirs are found in the low part of the trough line.?4?relationship between fault-rock combination structure and discovered oil and gas reservoirsThe sandstone oil and gas reservoirs of Es2,Es1,Ed,Ng and Nm,as well as fine-grained rock oil and gas reservoirs of Es3 and Es4 that have been discovered are mostly distributed in the fault-rock combination structure cutting the main source rock strata of Es3 and Es4.?5?preliminary exploration proposalsThe save-uplift composite structure of the source rock system and the fault-rock composite structure cutting the source rock have a controlling effect on the formation and distribution of oil and gas reservoirs from the Es4 to the Nm formation.In the exploration of sandstone oil and gas reservoirs in the Es3 and Es4 sections,the controlling effect of the Concave-uplift composite structure in the T₆ formation should be emphatically analyzed.In the exploration of sandstone oil and gas reservoirs of Es2,Es1,Ed,Ng,Nm and fine-grained rock oil and gas reservoirs of Es4 and Es3,the controlling effect of fault-rock combination structure should be emphatically analyzed.