| The thermal history of sedimentary basins plays an important role on studies of petroleum exploration and hydrocarbon accumulation. The tectogenesis of Indosinian movement Yanshan movement and Himalayan orogenic movement reconstruct Dongpu sag and surrounding regions. Different basin types of Palaeozoic Mesozoic and Cenozoic lead to the complication of thermal evolution degree and paleogeothermal gradient of the source rocks. Using mobilistic theory and geoevolutionism as the governing principle restored thermal history of region of interest by the combination thermal history and the region structural evolution. The present-day temperature and palaeogeothermal are same important. By combination the seismic, drilling and outcropping data, according to the prototype basin of different time and thinking fully the influence of the superimpose and reformation by multiphase and multistage tectonic movements to geothermal, upbuilded conceptual model of thermal history, simulated the thermal evolution of the source rocks of Paleozoic in different tectonic units in accordance with the evolutionary phase, estimated the favorable hydrocarbon generation areas.1 Based on volumes of temperature data, the distribution of temperature is affected by deep-crustal structure and tectonic setting. Crust thinkening from Dong sag to middle part of Lingqing depression, Kaifeng depression has a more thickness Crust than Lingqing depression, and it is joint controled by the NNE and NWW faulting, which lead to the decrease of temperature gradient, the corresponding gradient is 34℃/km, 27-32℃/km and 23.3-29.1℃/km respectively. The distribution of temperature is affected by structural framework, tectonic position of buried deeply has higher temperature and the upwelling area has lower temperature at the same horizon.2 On the basis of analysis structural feature, inclusion and apatite fission track sample was retested oriented. The type of palaeogeothermal in Dongpu sag and surround regions was divided into two types by multidisciplinary analysis multiple data, (1)present-day temperature is close to palaeogeothermal,(2)palaeogeothermal is higher than present-day temperature. On the studies of Lanliao faulted zone, Tangyin graben, uplift of Linqing depression and central uplift belt of Jiyuan depression, temperature gradient of Triassic, Early-Middle Jurassic, Early Crataceous, Early Teriary is 31.7℃/km,27.8℃/km,40-50℃/km, 30-37℃/km, respectively.3, Using feature of structural evolution and multiple geothermometer, four thermal evolution phase were divided .The paleogeothermal gradient of critical time (late Mesozic) is 35-45℃/km and heat flow is higher than 90mW/m~2, and the degree of thermal evolution rising rapidly. A tectonic heat event happened in Late Mesozoic era in 130-140Ma.It is very important to hydrocarbon generation, migration and accumulations. Oil source rock of mole track and depression marginal zone are in largest degree of thermal evolution and still in the phase of hydrocarbon generation nowadays. To the oil source rock in depression, Cenozoic is the time of thermal evolution increasing and secondary hydrocarbon generation for the great subsidence.4 Combination geothermometer and basin modeling, reconstructed thermal history of different tectonic unit, five type of history of thermal was divided, i.e. (1)sustained elevating temperature after Mesozoic, (2)sustained elevating temperature after Mesozoic-Early and temperature drop after Neogene, (3)elevating-decreasing temperature alternately in early and late phase of Mesozoic and Cenozoic, (4) elevating-decreasing temperature alternately in Mesozoic and sustained elevating temperature after Cenozoic,(5)decreasing temperature for uplift. Viewed at thermal history, the first four types is beneficial to find gas.5 The secondary hydrocarbon of Dongpu sag and surrounding regions's has the lag effect obviously. The different tectonic unit has different history of hydrocarbon generation. Combination characteristic of structural evolution and condition of conservation, the beneficial secondary hydrocarbon generation district of Upper Paleozoic were ascertained, i.e. Eastern and Western depression of Dongpu sag, central uplift belt of Dongpu sag and Zhongmou sag.
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