| The thesis selects the Mesozoic and Cenozoic basins surrounding Daqing exploring region as to be main studying points. Based on studying the regional rock strata sequence, the author wants to reconstruct the evolution history of the Mesozoic and Cenozoic in the region. These conclusions may have grate theoretical and practice significants to the basic geology study in Northeast China, basins evolution and oil and gas perspective evaluation surrounding Daqing. The thesis main content compose of 4 aspects: 1. Based upon summarizing systematically the former references about the regional stratigraphy and paleontology, the author has discussed the Mesozoic and Cenozoic rock stratigraphic sequence surrouding Daqing region and their correlations. The thesis narrate more than 20 formations, including their definition, the character of their basic rock assemblages and stratotype section. As we know that the international stratigraphic chart place the boundary between Jurassic and Cretaceous at 145. 5±5Ma, and there are a great deal achievements have been made this 10years in paleontology studying and Igneous rock isotope age measuring in Northeast China, so the thesis emends some stratum age, especially some stratum units formerly thought to be Jurassic, such as: Jixi Group, Longzhaogou Group, Huoshiling Formation and Longjiang Formation, the thesis places them to be early Cretaceous. 2. After analyzing the Mesozoic and Cenozoic strata distribution and regional geology, the author finds that there are 5 regional unconformity, they located separately between late Triassic or early Jurassic and early Triassic, early Cretaceous and middle Jurassic, Late Cretaceous and early Cretaceous, Paleogene and late Cretaceous, Neogene and Paleogene, so the author can easily classify the Mesozoic and Cenozoic basin evolution to be 5 tectonic layers, namely: early and middle Jurassic tectonic layer, early Cretaceous tectonic layer, late Cretaceous tectonic layer, Paleogene tectonic layer and Neogene tectonic layer. 3. Through analyzing the regional and basin geologic information, the author discussed pre-Jurassic tectonic units classification and evolution, and concluded that the researching region locating in the east part of Tianshan, Inner Mongolia and Xingan orogenic belt, and its Paleozoic paleogeographic pattern is composed by a series of middle and small massifs, such as Jiamusi massif and Eerguna massif. These massifs were sutured in early Late Paleozoic, and formed a holly Heilongjiang plate, and the Heilongjiang plate sutured with North China plate along Xilamulun to Changchun suture in late Permian or early Triassic, and then, in middle Jurassic, which sutured with Siberia plat along Mongolo-Okhotsk suture and formed a unified Eurasia continent, and which indicate that it is the end of paleo-Asia ocean tectonic realm. It is also middle Jurassic that the Wandashan terrain finished the collision with Eurasia continent, and this event indicate the commencement of Pacific Ocean evolution. 4. The thesis has studied the regional tectonic setting during the Mesozoic and Cenozoic basin forming. The author conclude that there are 3 elements which affect the evolution of Mesozoic and Cenozoic basin in Northeast China, one is the subduction of Pacific ocean plate, the second is the lag effect of collision of Siberia plate and the last one is long distance effect of Indo plate collision with Eurasia. In one words, there are 4 circles in Mesozoic and Cenozoic basins evolution history, namely: J1-2,K1,K2,E. The thesis summarized each basin circles characteristic and typical basin. And the author finds that the pattern of basin evolution in the region is the basin forming stage and stressing reversion stage by turns, multi-stage development and superposition is main character of the regions basin evolution.
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