The Primary Research Of Relationships Between Fault And Reservoir Formation

By means of simulation test and geological analyze, the mail task of this article is to study the relationships between fault and reservoir formation, the clues is the oil/gas migration process when fault produced, oil/gas lie in fault and migrate from fault to sandstone.The paper has obtained mainly many productions and acknowledges as follows:1. Grains skeleton of source rock and reservoir bed are compressed before the fault produced. pore fluid pressure in stratum is high, which is hydrostatic pressure or exceptional overpressure.2. Fluid pressure in stratum step down rapidly when fault come into being, the compressed oil, water and gas travels rapidly depending on their expansibilities. Among the oil, water and gas, the expansibility of gas is maximum. The participation and saturation of gas, have the important impaction on oil/gas/water migration.3. Simulation experiments indicate: oil/gas float easily in faults. The possible reasons lie in, oil/gas form mutual recurrence channels lightly because the shape of pore in fault is compressed, the travel resistance is less. The vertical and lateral sealing have the important impaction on oil/gas migration.4. Oil/gas preferentially migrate to reservoir bed which its porosity are better and its displacement pressure is lower. On condition that the oil resource is abundance and pressure is enough higher, oil/ gas will migrate to reservoir bed which its porosity are baddish and its displacement pressure is upper.Oil/ gas enriched near the inject port firstly as it get into the reservoir bed. If the oil injects ceaselessly, oil/gas will migrate to else areas. The travel characters of oil and gas is different. Without the adscititious force, oil can migrate to updip direction in reservoir by self adjusting, but the gas migration is difficult.5. The region of Gaoqing carbon dioxide reservoir has consanguineous relationships with the strike sealing of fault. The process of gas accumulating showed that carbon dioxide prefer to migrate to reservoir bed which its porosity are better and its displacement pressure is lower.The Faults and cracks in Liangjialou oil field, is the important approach of oil/gas migration. bituminous veins in cracks of source rock and sandstone is the direct evidence of oil/gas gravitational differentiation in cracks.The distributional characteristics of carbon dioxide's content falling from south to north shows that, gas has the character of enriched near the resource in reservoir bed, and carbon dioxide migrate difficultly under flotational process in sandstone.