Abstract:

According to the pattern characteristics of dominant oilgas migration pathways of transporting layer, the patterns of dominant oilgas migration pathways are divided into three types of coalescence, divergence and parallel patterns. Through the analysis of characteristics of transporting layer of southern member 2 in the north of Wuerxun depression, the oilgas migration pathways of southern member 2 transporting layer in the north of Wuerxun depression in each geological period are studied based on the reconstruction of ancient burial depth. The direction and distribution pattern of dominant oilgas migration pathways of transporting layer in the member has similar characteristics in different geological periods. There are five coalescence areas. The cealescance density of dominant oilgas migration pathways in well Su 1,Su 21 and Wu 8 is big, the cealescence area of well Su 21 is at the edge of hydrocarbon kitchen, the cealescence areas of well Su 1 and Wu 8 is in the hydrocarbon kitchen, which is favorable for oilgas to accumulate and form oilgas reservoirs. The cealescence density of oilgas migration pathways in the two cealescence areas of the west of this region is small, they are outside the hydrocarbon kitchen, which is not favorable for oilgas to accumulate and form oilgas reservoirs. The industrial oilgas wells now are either in the cealesence areas of oilgas migration pathways or on dominant oilgas migration pathways, which is the important condition for forming oilgas reservoirs.

Key words: transporting layer, oilgas migration, pathway, the north of Wuerxun depression