| On the basis of predecessors’ research,seismic, logging, geology and testing data alluesed in this paper,the space matching relation of source rock, trap and the transportingpassag in the study area what are three main factors of oil and gas accumulation arecomprehensive analyzed. Its controlling effects on the distribution and the forming ofreservoirs are studied. That guids the next step to prospect oil and gas.The methods mainlyused and conclusions got in this paper are as follows:Based on3D seismic data, seismic section are tracked and the anticline in the study areaare determined. The axis of anticlinal gradually deviated to the east from north to south.Itwhole is a asymmetry anticline whose strike is NNW-SSE and the west wing is narrow buteast wing is wide and gentle.This is consistent with the3D geological map of top of the oillayer.Tectonic units in the study area divided into four units with the dip angle map: thenorthwest slope area, southwest slope area, the central anticline belt and southeast gentleslope zone.And the characteristic of fracture geometry in the study area is analyzed, including thefracture orientation and density, displacement, extending length, the combinationcharacteristics in horizontal and section and fault concentrated belt, the characteristics offracture developed in the different structural are concluded.At the same time, the growthindex of fracture section extending length and the history of fracture developed in the studiedarea were studied, and the activity time of fault is determined.Combined with thecharacteristics of geometry and kinematics, ruptures in the study area are divided into sixlarge fracture systems.Through the study on the characteristics of formation and sedimentary determined thepattern of source rock, reservoirs and cap rock in the study area is the mode that source rockis on the up who is cap rock in the same time and reservoirs is below..By predecessors’studyon the oil source in the study area,the oil and gas source is found. Calculating hydrocarbonborn and expulsion intensity from source rock,oil and gas source coming in two direction thatsouthwest and northwest are known.Counting up fault trap types developed in the study area, the mainly type isfault-lithologic trap, the second is fault trap and anticlinal trap.The trap types in the central anticlinal belt are the most in the study area and structural trap and fault-lithologic trap aredeveloped widely. Followed by the southwest slope zone and the northwest slope zone, theeastern ramp zone is the lest.Through the analysis of tectonic and sedimentary characteristics in the study area, thispaper sums up the three main transportation systems developed in the study area:(1)anticlinal-lithological ridge conducting system, mainly distributed in the zone that near theaxis of the central anticlinal;(2) connecting sand body-fault conducting system, mainlydistributed in southwest slope area;(3) fault-lithological ridge conducting system, mainlydistributed in the northwest slope area.Comprehensive analysis of the distribution feature of trap and conducting system, threespatial relationships of the source rock, trap, and transportation systems are summed up:(1)the mach relation of source rock and trap connecting by fracture, mainly distributed in thenorthwest slope area;(2) the mach relation of source rock and trap connecting by fracture-structure ridge, mainly distributed in the zone that near the axis of the central anticlinal;(3) themach relation of source rock and trap connecting by fracture-sand body, mainly distributedin southwest slope area.The comprehensive analysis of the space matching relations between the accumulationelements, the controlling effects on the forming and distribution of reserviors are summarized:(1) the trap that connecting transportation systems is advantageous to accumulate oil andgas;(2) different types of transportation systems controls different numbers of oil and gasformed;(3) different types of transportation systems controls the distribution of reservoirs. |
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