| Ordos Basin locate in western North China Block, betweem Qinling-Qilian orogen and Yinshan-Yanshan orogen in the north and south respectively. It is considered formed along with the closure of Xinmeng ocean and subduction of Qinling ocean in late paleozoic. Voluminous sedimentary materials were transited into the ambient basins and deposited there during the process of continent-continent collision, extrud orogeny and erosion between North China Plate and Qinling block, siberia plate in Ordos Basin, it can provide powerful evidence for exploring orogenic process.Clastic sediments is the excellent carrier for these orogenic process, transporting rocks can lose or change minerals, but a lot of information from sources can be brong to destination. Heavy minerals of sandstones can judge source area lithology because of higher stability; matrix minerals can indicate provenance direction because they are the major mineral components; debris can be used to sure characteristics of parent rocks because it keep characteristics of parent rocks. Detrital zircons is of extremely stability, and it distribute of detrital sedimentary widely. It construct age spectrum of detrital zircons in the Shiqianfeng, He 8 and Shanxi Formation of the Low Permian, Upper Paleozoic in Ordos basin, and research on chronology and characteristics of parent rocks in provenance tracing, using techniques of LA-ICPMS in situ U-Pb isotopic dating and trace element analysis of detrital zircons, accompanied with comparative study on petrology of skeleton and heavy minerals and their assemblages in the sandstones.Through observing the drilled rocks, elevating the casted rock slice, analyzing grain size, and by detrital zircon U-Pb dating and other analysis and measurement methods on Upper Paleozoic Yanchang zone in the Ordos Basin, this paper has done the folowing systematic researchs on the lithology characteristics, characteristics and composition of the light and heavy minerals and these minerals distribution in the vertical and horizontal dereciton, detrital zircon geochronology and other researches for Shi qianfeng Group, He 8 section, Shanxi Group sandstone reservoir,discussing of its provenance, source rock properties and the impact of the reservoir.The result of the research showing that, the characteristics and composite of the light and heavy minerals in the Shi qianfeng Group, He 8 section, Shanxi Group of upper Paleozoic Yanchang zone in the Ordos Basin were divided into three source directional zones. The first is the Middle zone of Yan'an-Yanchang, the grains of the sandstone is steady and fine, with high maturity and high content of quartzes, the debris concludes metamorphic, sedimentary,igneous debris, and the heavy minerals contain zircon and ion minerals mainly. The second zone is the Northwest zone of Ansai-Zichang, the Sandstone particles is middle-coarse and sub-angular, the quartz content is high, almost no feldspar existed, and the mainly heavy minerals are iron minerals, chlorite and zircons, indicating that it originated from igneous and metamorphic lithic debris. The third zone is the Northeast zone of Suide-Qingjian, the sandstone particles is middle and sub-angular, the sandstone grain contains mostly quartz and with little feldspar, and metamorphic, sedimentary, igneous debris and no more feldspar, the heavy minerals are mainly iron minerals, chlorite and zircons, indicating its source is sedimental and metamorphic rocks. From the Ganquan to its south is the southern zone, the sandstone grain is mainly quartz,and the content of the feldspar is higher than the other zones, and the debris is manly sediment and metamorphic rocks. The little igneous rocks contains mainly heavy minerals of iron minerals, chlorite and zircons, indicating that its source is metamorphic, sedimentary, igneous rocks..It's can be concluded that the provenance is mainly from the early or meso proterozoic khondalite belt and early proterozoic TTG gneiss in the substrate rocks of north Yinshan mountain land mass early or meso proterozoic, hercynian rocks, metamorphic in the southern Qinlin orogenic belt, paleozoic metamorphic rocks and magmatic results by the chronology of detrital zircons. The rest is from archaeozoic metamorphic rocks in Yinshan land mass and Longshan TTG gneiss.The terrigenous clasolite is from the provenance bed rock. It forms the sand matrix of sedimentary basin. The reservoir properties of sand are related with the composition of the terrigenous clasolite, and depend on the lithology and rate of decay. The terrigenous clasolite is from the khondalite, gneiss and granite. Because of the warm and moist paleoclimate the unstable feldspar and clasolite.Because the warm and wet peoclimate, the weathering especially the chemical weathering is very strong,and the unstable feldspar and debris were completely chaged.The grains of sandstone of middle zone is almost quartz, the average porosity and permeability is high, and the prosperity is good, which is main gas area, and in the north and south region,the feldspar and debris is higher than the middle region, the prosperity of the reservoir is weak. This is significant to the theory and practices to prospect the favorable exploring region and promote the exploration of the gas in the Ordos basin.
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