Sedimentary Characteristics And Favorablereservoir Prediction In Sand Three Sections Of Qingshui Sag In Liaohe Oilfield

Qingshui Sag is a main area to produce oil and gas in Liaohe Depression, the exploration of shallow layer has been into highly mature stage. Although oil and gas production are increasing in recent years, reserve resources are still insufficient, and the difficulty of oil and gas exploration is increasing. In order to explore fine oil and gas, the establishment of the sequence stratigraphic framework is an important basic, and has very important practical significance. This paper is in view of three sections in Liaohe Qingshui Sag, and on the basis of core analysis data, using electric logging curve, seismic data to carry out in-depth study of stratigraphic framework.Because research on deep layer is little, the study layer is huge thick and change of thickness is big, study on the sequence, different people have different opinions, using electric logging curve only can not be accurate. So when doing sequence division on the combination, we use seismic data such as ultra, toplap, cutting characteristic, electric logging curve characteristic such as low gamma ray, low acoustic time. Through the study on sequence layer of Qingshui Sag sand three, we divide sand three into one level 2 sequence, three level 3 sequence,six level 4 sequence, summarizing the electrical characteristics and lithologic characteristics of this blocks. The bottom interface of Level 2 in sand three, seismic section on good continuity, super and local cutting formation, lithology and color mutations. The top interface of Level 2 in sand three, seismic section on performance for a strong continuity better seismic reflection amplitude, phase axis, on the top is for clear ultra, under the interface is parallel to the contact. In conclusion, we divide ES31 into two Level 4 sequence, Es32 into three Level 4 sequence, ES33 into only one Level 4 sequence.On the basic of the above, using the data of core observation and in combination with core rock facies inside, sedimentary structure type, boulder clay characteristics, vertical rock characteristics, determining the main phase type is sublacustrine. To analysis this interval sedimentary facies of this blocks, to draw sedimentary facies map. At last, using seismic section to forecast favorable reservoir, selecting the favorable reservoir optimization,providing geological basis for oil and gas exploration in this area.