| Hailar Basin has already gone through 20 years of exploration history since seismic exploration in 1982. Although a definite breakthrough, there is still great potential that needs to be further dug. As a typical rift basin, the oil geological conditions are complex, the depression has characteristics of a multi-material source, near the source material, a narrow phase-band, large phase-change, etc; basin complex, fault development, oil and gas reservoirs of varying types make many of the fundamental oil geological knowledge still needed to be deepen and strengthen, such as oil-generating conditions in bits of layers in the depression, oil and gas sources and accumulation process and other issues. In this paper, it adopted a number of new technologies and new methods, such as analytical techniques of fluid inclusions and carbon isotope, nitrogen-containing compounds, identification of specific biomarkers and whole-rock macerals, studied Wuerxun oil-generating source rock characteristics and oil-generating model, determined the distribution range of the oil-generating source rock, through combining with geological studies, using new theories and new information; On the basis of the characteristics of oil and gas geochemistry, analyzed geochemical characteristics of crude oil, determined the source of crude oil; studied the hydrocarbon migration direction and migration channels; determined the gas injection and accumulation time, analyzed the process of hydrocarbon accumulation. Many innovations have been achieved in oil and gas generation and accumulation:Through researching the hydrocarbon source rock, it indicated that the hydrocarbon source rocks have been studied through the hydrocarbon source rock evaluation criteria, K1n1 is the best hydrocarbon source rocks in this area, K1n2 is in the next place, K1d1 is the middle-source rocks and can be used for the sub-first grade source rocks, K1d 2 and Tbm group hydrocarbon source rocks are the poor or non-hydrocarbon source rocks. Establishing the model of hydrocarbon of formation-expulsion of source rocks, pointing out that threshold of hydrocarbon generation is 1450m in North Wuerxun Depression, is 1500m in South Wuerxun Depression, threshold of hydrocarbon expulsion is 1750m in North Wuerxun Depression, is 1800m in South Wuerxun Depression. The crude oil in Wuerxun depression have a good similarity in crude oil properties, ethnic composition, the distribution characteristics of n-alkanes, which reflected that the crude oil comes from the same parent source or source rocks of similar depositional environment and thermal evolution. Applying gas chromatography parameters and various biological markers, carried out the contrast between crude oil and source rocks, showed that crude oil in Wuerxun Depression mainly comes from the Nantun Group dark mudstone, and has a close relationship with the K1n1. Using nitrogen-containing compounds and other indicators determined the direction of oil and gas migration, studied the oil and gas migration pathway, pointed out that faults and unconformity surface is a major oil and gas migration channels. Multipurpose using the method of trap formation period, source rock generation and expulsion history and homogenization temperature to determine that a time of hydrocarbon accumulation is mainly in the sedimentary period of K1y and K1q. Oil and gas accumulation process analysis showed that a large number of oil and gas accumulation is in the sedimentary period of K1y 23, since the deposition of K1q, the strength of hydrocarbon generation and expulsion has weakened, but did not stop the process of hydrocarbon generation and expulsion.
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