| This paper systematically studied the characteristics of crude oil and source rocks, the crude oil and oil source correlation and control factor of hydrocarbon accumulation, based on the practice oil and gas exploration and full absorption of all previous research results on the Dong pu depression. Combined with the hydrocarbon generation and expulsion history of the source rocks, the hydrocarbon migration and accumulation process, and periods of accumulation in the study area, the mode of hydrocarbon accumulation was established.The Wendong graben belt, Wendong rolling anticline belt, Wendong anti-ridge belt were controlled by the faults 1 and 2. These structural belts had a high degree of structural inheritance, so structural integrity is high. The salt beds of Sha1 to the upper Sha2 and Wen 9 that were main controlling factors for oil and gas accumulation in Wendong area are regional cap rocks. The earlier-forming Horst in the Wenzhong the had high oil and gas accumulation as a result of large closure proportion and altitude of the structure traps. On the contrary, the Horst in Wenzhong formed late, had less oil and gas accumulation because the faults block was broken. The structure of Wenxi area near to the depression was controlled by the fault 2 formed late directly, There were many kinds of fault block type and lateral worse closure conditions, so oil and gas accumulation was controlled by the local tectonic setting.By analysis of the geochemical characteristics of source rock and crude oil, the spatial relationships of the source-oil pool was established. The oil source correlation indicates that the oil and gas mainly came from the Sha3 source rocks, Vertically, because of similar geochemical characteristics of crude oil, the source should be the same source rocks, but there were some differences in the maturity of crude oil, the maturity of crude oil became high with depth, the maturity near the depression was the highest. There are also some differences in biomarkers of crude oil between in Wendong and Wenxi areas. The crude oil in Wendxi area with high gammacerane and pattern of anti-"L" of C27 ~ C29 sterane distribution is from the Wendxi area. The crude oil with a high gammacerane content and asymmetric "V"-type distribution of C27 ~ C29 steranes C27 was mainly from the Wengxi area and the Qianliyuan depression with super-salt sedimentary environment. The faultâ…¢, was boundary of hydrocarbon source rocks between the Wendong and Wenxi area. To west of faultâ…¢, the crude oil was mainly from the Wenxi area and Sha3 source rocks near the depression, to east, the crude oil was from hydrocarbon source rocks in the Qianliyuan depression and the Wenliu areas.By analysis of salt rock characteristics, abnormal pressure distribution, fault characteristics and configuration of sand body with faults, the results showed that the oil and gas enrichment was controlled by many factors that varied with different areas. Controlling factors for oil and gas distribution in study area were the oil source rock, the configuration of fault with oil source, reservoir and capping conditions which co-determine hydrocarbon abundance in the various structural zones.The main hydrocarbon migration and accumulation in Wenliui area was the Dongying period. The pool of Sha3 member in Wendong area was two oil accumulation periods which was similar to sha3 member in Wenxi area, the first was the sha1 to the Dongying sedimentary period(33 Ma~23 Ma)),especially, the extensive oil filing occurred at late the Dongying sedimentary period, the later is the Guantao formation to the Minghuazhen Formation sedimentary period; The reservoir forming period of Sha2 is later than that of Sha3 member, it is a single-period reservoir forming that was result of re-adjustment of the Sha3 reservoir in active tectonic stage, its main accumulation time is from the late Dongying deposition period to the uplift period (30Ma ~ 17 Ma). The Dongying formation reservoir in the Wenliu area formed late than the Sha2, its main forming time was from the end of the Dongying period to uplifting period.In short, the Sha3 pool in the Wenliu area was formed early, but was finalized late. The Sha3 pool in the Wendong area showed earlier forming time than in the Wendong area, vertically, the pools in mid-depth and deep formations were earlier than in shallow formations. there were three types of the oil and gas accumulation model : Primary pool near to depression, Adjustment pool controlled by source rock and fault, and Secondary pool with shallow depth.
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