| This dissertation is written on the base of the project "Study on temperature-pressure fieldevolution and hydrocarbon accumulation mechanism in Damintun Depression", which isprovided by Liaohe oil field of CNPC. The main leading ideas include petroleum system anddynamics of accumulation theories. We discussed hydrocarbon accumulating processes ofdynamics and kinematics in Damintun Depression. Many advanced methods and technologies ofoil-gas geochemistry, reservoir geochemistry and basin modeling have been used, such as fluidinclusion Laser Raman spectroscop, Illite K-Ar dating, saturated hydrocarbon GC/MS,monomeric carbon isotope, nitrogen-containing compound and fluid heterogeneity. Hydrocarboncharacteristics, forming types, accumulation mechanism in this region have been well acquainted.At the same time, combining with accumulation background and energy field, we acquiredreservoir forming conditions and its controlling factors. Consequently, they help to forecasteffective oil-gas perspectives and choose available exploration targets. Damintun Depression is located in the northeast of Liaohe Basin, well-known as "small butfertility"and rich high-wax oil in the world. The total area of Paleogene is only about 800 km2and its geologic reserve is about 300 million tons. The fertility reserve is mainly owing to itsparticular conformation-sediment development history, appropriate geothermal-pressurecircumstance, more source sags, high quality sources, favorable conduit systems, near-sourcecharging, multi-play types. Advantageous accumulation background, accompanying withsecondary changing effects such as migration differentiation and biodegradation formed mutualoverlapping complex reservoir systems, including normal crude oil, high-wax oil and condensatereservoirs.The following conclusions have been drawn: 1. The characters of petroleum are complex, with normal oil whose waxy percent is less than20% and high-wax oil whose waxy percent is more than 20%. Comparing with normal oil, theenvironment of source rocks of high-wax oil features with poorer shale, higher salty andreduction, and the source features mainly composed with higher grade plant and lower gradeaquatic creatures by the analysis of crude oil physics nature, sterane, terpane and infraredspectrum. Detailed oil-to-source correlation shows that high-wax oil originates from "oil shale"of E2S4 , whereas normal oil sources from shale of E2S4 and E2S3 . The reasons of high-wax oil 2 1 4generation are mainly due to organic matter and sedimentary environment. 2. The pale geothermal gradient is higher than the present, and in Anfutun and RongshengpuSags, the PGs have reached 41℃/km and 36℃/km. The variety from rate of deposition and basintectonic subsidence to geothermal gradient have come into being properly lowthermo-developing history, which made high-wax oil generated and enriched and preserved afterpeak time of hydrocarbon generation. Four types of compaction in Damintun Depression areclassified from the characteristics of mudstone compaction. At planes, the strong overpressure isalways formed in the sedimentary center of every sag. Yet From the point of profiles, it is mainlygenerated from bottom of E2S3 member to inside of E2S3 and E2S4 members. Overpressure is 3 4stronger and formed widely. Pressure evolvement can be divided into two phases of stressaccumulation and release. The under-compaction and hydrocarbon generation are the leadingmechanisms for the formation of the overpressure in this region. 3. Petroleum charging history in Damintun Depression is also acquired by means of IlliteK-Ar dating and fluid inclusion homogenous temperature technologies. Integrating withpetroleum generation history by basin modeling technique, conclusions are drawn:To thereservoirs of Paleogene and Archean, one mainly charging period existed, w...
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