Lean Oilfield West Kongdian Igneous Evaluation Of The Accumulation Conditions

The Le-an oil field is located on the southern slope of Dong-ying sag. There are two sets of Ek basalt in its western block. Depending on the drilling , the logging and the seismic date, tha Ek basalt has the characteristics of high resistancs, the low sound wave defferance and faradic conductance, the smooth curve of self potential. The seismic wave shows strong board reflactance. There are twice vocanic activities, and its plane distribution shows steady state comparatively. The break forth fashion is 'cranny overflow' . The crater located nearby the CA012 and CA031.The reservoir condation can be sum up in several aspects. Because it is easy to be dissovled, The basalts in this area has more cracks and dissolved caves. Though it is filled later, the adventage lithology is fairly developed. The contrastion of oil characters shows that the petroleum came from the main hytracarbon source-Bo-Xing sag and Niu-zhuang sag. The Ng basalt which distribute stably act as the regional top formation. Several set of mud rock deposited whose thickness between 2 to 5 meters are the local top formation.. The Shi-cun faultage crossed formations from Ng to Ar. The Chenguan-zhuang faultage crossed formations from Es to Ek formations. So the petroleum produced in the main hytracarbon source could move to the Le-an oil field. Using the saturation-pressure, the creation time of reservoir evaluated is in the late of Nm. The basalt traps formed in the late of Ng. So in the aspect of time, The basalt traps are efficient. When the pressure which put on the faultage surface is bigger than 5MPa, and the content of mud in the faultage exceeds 25%, we can say the faultage is closed. According to the calculation, the pressure put on the surface of Shi-cun faultage is 7. 27 MPa, and the content of mud in the faultage is 26.9%, so the Shi-cun faultage is closed. And the conservation conditions are favorable.The results of reserch work show that the area of CA012 , CA031, CA060 andthe area near the Shi-cun faultage are adventage exploratory targets. The succeed possibillity is bigger.But it has the high venture in all. It is suggested to frac-pack, to drill directional well to test oil in steam stimulation. Logging restricked seismic reverse should be done in all area to evaluate the reservior roundly.