| With the country growing demand for oil and gas resources, search for replacement with the strategic significance of new exploration areas becomes more urgent. Reconstruction of basin strata of Late Paleozoic basement thermal history is deep basin resources to open up new areas for exploration the key is to identify the basin basement strata of Late Paleozoic deep basin is as effective source rocks in this growing concern by people core. Basin and its peripheral widely developed in the late Paleozoic strata, the depth varies greatly (1～7km), generally 3～5km, mainly distributed in the western rift zone, the central uplift area and the southeast uplift zone, lindian region's most thick, to 7km, followed Sanzhao area, the thickest Zhaodong to 6km, the thickest northeast uplift for the 5km, heiyupao-Daqing area thick and wide distribution. Rocks include shale, slate, phyllite and carbonate rocks like slate, rock and mineral composition and structure of very low grade metamorphism show that more and more information Basin basement Paleozoic strata have important petroleum geological significance. Basin marine strata of Late Paleozoic basement, high abundance of organic matter, organic matter typeⅡ2-Ⅲtype, high maturity (Ro> 2.0%), had Carboniferous-Permian gas reservoirs found in a number of and CO2 gas reservoirs. Exploration results have been revealed Basin bedrock weathering crust, rock fissures exist in natural gas, Zhaoshen-1 Well in the basement crust 1×104m3 of industrial air by one day, Wang-902 well, Ren-5 well in the basement rock of any drilling case of gas. Existing research shows that Basin deep bedrock weathering crust, bedrock fractures and found the upper reservoir of organic deep source gas, may be derived from the Carboniferous-Permian strata. The results show that surrounding the basin, northeast China developed the Early Devonian, Late Carboniferous-Early Permian, the Permian and Late Permian, four sets of dark rocks. Longjiang areas of the Permian field study found that dry asphalt is Carboniferous-Permian rock itself generated.The northern basin basement metamorphic thermal simulation results show that metamorphic certain hydrocarbon potential, the equivalent of source rocks Ro 2.0%to 3.5% range, hydrocarbon intensity 3.0×108～23.8×108 m3/km2. Rock thin section, illite crystallinity, geochemical analysis shows that today the formation of vitrinite reflectance was 2.05%～7.60%, in most parts of the slight modification that the very low-grade metamorphism, with relatively high abundance of organic matter degree, the whole basin, the average organic carbon 1.17%, Sishen-1 Well 1289.5m thick strata of organic carbon values as high as the average 1.45%.Thermal history of sedimentary basins reconstruction is to restore the ancient geothermal field and its time evolution. The current restoration of ancient sedimentary basin commonly used method of temperature there are two categories:the first is the use of thermal indicators to simulate a variety of ancient basin thermal history, the main palaeothermometry including organic maturity Ro, fluid inclusions, clay minerals, phosphorus ash fission track and other stone; the second is the thermal dynamics of basin evolution model to study ancient temperatures. Late Paleozoic strata in northern basin depth of large, its maximum temperature experienced by the general over the apatite fission track annealing temperature, it is difficult for the system to their apatite fission track analysis. The main research method is combined with Ro palaeothermometry heat conduction numerical simulation.Different tectonic units of different uplift rate of erosion can result in different regions showed different degrees of thermal evolution. Uplift rate of denudation in the small area, low levels of thermal evolution of the rock surface; in the uplift rate of denudation of the region, a high degree of thermal evolution of surface rocks. Uplift rate of denudation and erosion of small areas of uplift in areas of secondary burial in the process of thermal evolution and hydrocarbon generation with different characteristics. Thermal history of recovery, you first need to restore accurate to history, but to the history of restoration of erosion thickness is one of the important parameters, erosion process is an important part of burial history. Basal Carboniferous Basin-Permian suffered a degree of erosion, denudation in different wells varies greatly. In this study, according to the geological basin characteristics and the data collected, use the principle of material balance based on the density difference method to restore law and Ro the northern basin of the Upper Paleozoic basement denudation. The results showed that the northern basin of the Upper Paleozoic denudation has certain rules, in the center of the basin near the central uplift, and southeast rift zone Xujiaweizi depression denudation small, out denudation increased the minimum amount of erosion 91.6771m, of up to 4045.7269m, the more obvious differences.EASY%Ro method is the most accurate model of Ro, is more widely used methods in moderate to high maturity, when more accurate. This study is in the basin to restore the basis of the history, use Ro data, mainly using the EASY% Ro model, and supporting the use of TTI model, restoration of the Upper Paleozoic basin in the Mesozoic thermal evolution of the second degree before burial, the highest ancient temperature, and the Mesozoic Paleozoic secondary burial on the degree of thermal evolution, and finally, using finite element modeling, simulation of early Mesozoic and Cenozoic magmatic intrusion in the Late Paleozoic strata in the maturity of organic matter.Basin north of the Carboniferous-Permian generally higher degree of thermal evolution, the majority of vitrinite reflectance is greater than 2%, but in different regions, different structural parts of the maturity of organic matter is very different. In the basin, the current drilling data indicate that the northern basin of Carboniferous-Permian the greatest difference between the top of the depth of 4060m, the most shallow wells for Ren-7 well (537m), the deepest well as Songji-6 well (4597m), As the depth of the different degree of thermal evolution was significantly different. In addition, surrounding the basin, the Upper Paleozoic of the thermal evolution of the basin basement compared to the more obvious differences, analysis of the formation of the main reasons for this difference is the region of ancient thermal field, opposite the settlement, the difference of uplift, magmatic activity fault activity. For the Carboniferous-Permian strata and then buried before the restoration of the thermal evolution degree, use Ro data in this study, using the time-temperature index (TTI) model. The results show that the Carboniferous-Permian Ro after the second burial buried more than twice before the Ro, the role of the eastern region of the secondary burial of the Carboniferous-Permian thermal maturity of stronger than in the western region, some areas buried before the second or even lower than the thermal evolution of the overlying Mesozoic its current degree of evolution.In the sedimentary basin, for extrusive rock, due to its rapid cooling after the emission, its underlying sedimentary strata in the thermal evolution of organic matter affected to a lesser extent, even as the heat emitted from rocks generated hydrocarbons, in the absence appropriate storage conditions, it is difficult to save. For intrusive rocks, their formation is a relatively slow exothermic process, so its rock in the evolution of organic matter will affect, using the finite element method this magmatic intrusion of heat conduction modeling, to analysis magma intrusion on the thermal evolution of organic matter surrounding the impact. The results indicate that the intrusion of a 50m wide rock, about 100m away from the rock, within 200 years after the intrusion of magma, the temperature rising rapidly, it began its sharp decline, but the cooling rate is lower than the rate of warming, and in from the rock over 200m office, the degree of its temperature is not obvious. Magma intrusion in 4000, the rock temperature and rock temperature tend to the same temperature within the range of 5℃. With increasing distance from the rock, heating up more and more small extent, its because of the warming caused by magma intrusion temperature of the maximum time to reach more and more later. Magma intrusion on the surrounding temperature field range of about 800m, However, the more away from the mass, the smaller its temperature range, but from the beginning to heat up the temperature dropped to normal temperature gradient, the more time they experienced increasingly short, so by the surrounding magma intrusion caused the change in the maturity of organic matter, this range will be smaller. The intrusive rock 50m 50m away from their place can cause the increase of about 0.3% Ro,100m office about 0.15%,200m office about 0.02%, the effective impact of the total area of about 200m. 100m of intrusive rock at a distance of 50m Ro place can cause the increase of about 0.97%, 100m Office, about 0.4%,200m office about 0.16%,500m office about 0.05%, the effective impact of the total area of about 500m.Basin strata of Late Paleozoic basement is mainly affected by the oil and gas prospects of the development situation of the Late Paleozoic strata, the second degree of thermal evolution before burial, secondary burial in the process of thermal evolution of control. Meet the following conditions for oil and gas in areas with good vision:1, large thickness of the Carboniferous-Permian development zone and adjacent areas; 2, before the lower Mesozoic thermal evolution of the region, the new generation of strong thermal effect areas with higher intensity of hydrocarbon; 3, suffered minor uplift erosion, thick in the overlying Mesozoic and Cenozoic strata of the region; 4, Mesozoic and Cenozoic volcanic activity, magma intrusion and the end of hack so deep thermal heating effect strong areas. Finalized the western rift zone, northeast off the Suihua rift uplift area, southeast rift zone Xujiaweizi depression, Lanxi uplift and faulted transition zone with Miaotaizi four favorable prospecting area.
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