Abstract:The Yixian Formation is the most important bed for Jehol Biota. A lot of fossils preserved well of Jehol Biota were found in Yixian Formation which recorded the important information of the Jehol Biota evolution. In order to understand and rebuild the living environment of the Jehol Biota, it is necessary to carry out further sedimentary environment studies of Yixian Formation. The aboundant informations of sedimentary environment were recorded in several carbonate interlayers in the Yixian Formation of Western Liaoning. Through the studies of the carbonates, the lost environmental informations of the clastic rock can be obtained. The studies on carbonate and clastic rock provide scientific evidences for rebuilding the palaeoclimate, palaeogeography and palaeoecology of Yixian Jehol Biota of Western Liaoning. Eight lithotypes of carbonates have been identified by studies in the field and laboratory. The environmental analysis has been done by studying the sedimentary characteristics of the carbonate. The field works indicate that the development of the carbonate interlayers has the tendency of increase in terms of the layers and carbonate content to the southern direction of the basin. The palaeoenvironment of the Western Liaoning was dominated by shore-shallow lacustrine facies in Yixian period, and the carbonates mainly deposited in very shallow depressions on the floodplain as well as slight-brackish water in shore-shallow lacustrine environment. When the carbonate deposited, the climate was relatively dry and hot, the lake hydrology tended to close, volcanic activities were frequent and the lacustrine water supply was less than evaporation.

Abstract:The biotite adamellite intruding in Proterozoic metamorphic basement of the eastern part of the Kuche depression belongs to K-high calc-alkaline igneous rocks, and it is characterizes by SiO2-rich, alkaline-rich, K-high, low-TiO2 and metaluminous rock with A/CNK= 0.92~1.15. The adamellite enriches in elements such as Rb, Th, K, Nd, Zr, Y and Tb, and depletes in elements such as Ba, U, Nb, Ta, Sr, P, Sm, Ti with negative Eu anomaly（Eu=0.06~0.11）. Geochemical features of the granitoid rocks reveal its derivation from partial melting of middle-lower crust. In situ zircon U-Pb LA-ICP-MS dating on the magmatic genetic zircon yields an age of 646.5±3.9Ma, representing the emplacement age of the granites. Combined with regional tectonic analysis, it is concluded that the Neo-proterozoic magmatism is resulted from the response of basement of Tarim craton to the Rodinia splitting.

Abstract:Detailed zircon U-Pb age measurements were done on the Qinjia granite. These zircons have high Th/U ratio with zonal structure, which indicate magmatic zircons. The ziron U-Pb age for three granite rocks are 412.4±1.8Ma, 434.8±1.7Ma and 442.4±1.8Ma, respectively. The results show that all the granites formed in late Ordovician to early Silurian, which reflect the important stage of Caledonian magmatism, and provide a strong evidence for further understanding the Caledonian magmatism and its geodynamic process in South China.

Abstract:Abstract：It is widely believed that there were double strata (or three strata) of Pre-Sinian period of Western Margin of Yangtze Terrane, which could be divided into the lower crystalline basement and the upper fold basement. Hekou group was recognized as a transition layer between these two, and its property and age were still having much controversial. Advanced study of Hekou Group would have important implications for understanding of the feature and evolution of the basement structure of Western Margin of Yangtze Terrane. Here we reported 13 groups of zircon SHRIMP U-Pb ages from the diabase that intruded into Hekou group, and obtained 1710±8Ma concordant U-Pb age, which indicated that Hekou group was formed earlier than that age. According to large numbers of previous isotopic ages, Hekou group should be formed during 1817-1710Ma, later Paleoproterozoic.The age of the diabase reported in this study, has confined the upper limited age of Hekou group, and has great significance in further research on the Precambrian tectonic stratigraphy, formation and evolution of Yangtze Terrane.

Abstract:There is a large numbers of mantle xenoliths derived from the Cenozoic basalt in Huinan, Jilin province. The mantle xenoliths are dominated by spinel lherzolite. Equilibrium temperature calculated by the mineral chemical compositions show that temperature is within the range of 982-1085 ℃. As revealed by the oxidation decoration technique, the samples have undergone dislocation creep dominated plastic deformation, resulting in different kinds of the dislocation structures. By using the size of subgrain, the differential stress of olivine is estimated to be in the range of 21.3-36.5 MPa. The LPOs of olivine, which is measured by the EBSD technique，show A-type olivine fabrics as a whole. The variation of temperature and fabric and seismic anisotropy of LQLW08-18 suggest that the temperature may have a effect in preference to the [100] crystal axis. According to the study of olivine and peridotite anisotropy and the mineral compositions in the peridotite, the orthopyroxene can reduce the overall effect of the anisotropy. Different kinds of rheological parameters and fabrics characteristics not only provide basic information and restrictions for the further study of the upper mantle but also show the mantle heterogeneity and the replacement (chemical erosion) may be the main dynamic mechanism of destruction in this area.

Abstract:Chahansala gold deposit, a newly discovered gold deposit in Western Tianshan, locates in the west of Yilianhabi’erga arc-trench belt of Later Paleozoic and belongs to tectonic breccia altered rock-type. Our study about the fluid inclusions that in the mineralization stage veins indicates two types of fluid inclusions that as follows: ① two-phase liquid-vapor inclusions and ② three-phase CO2-rich inclusions. Their homogenization temperature ranged from 142℃ to 391℃ and 288℃ to 399℃, the salinity ranged from 2.24% to 7.73% and 1.22% to 2.39%, and the homogenization pressure ranged from 0.274Gpa to 16.35Gpa and 187.0Gpa to 240.7Gpa, respectively. The fluid inclusions was characterized by low-meso temperatures and low salinity, and is CO2-H2O-NaCl system. The ore-forming depth was about 1.1km. The change of ore-forming stress caused fluid immiscibility, and led to gold precipitation possibly. The δD and δ18OV-SMOW of the hydrothermal gangue mineral quartz are -92‰~ -74‰ and 11.8‰~12.6‰, respectively; the δ13CV-PDB and δ18OV-SMOW of the hydrothermal gangue mineral calcite are -8.92‰~ -8.06‰ and 13.45‰~17.18‰, respectively. These stable isotopes studies reveal that the ore-forming fluid of chahansala gold deposit was mainly composed of magmatic water, and formational water.

Abstract:This paper reports the basic unit (i.e., the sedimentary sequence is composed of fine-grained sandstone, siltstone, and shale) of Xujiajuan Formation of the Xiangshan Group, Ningxia, China. This unit is divided into a lower dense flow deposit division (Ⅰ), an intermediate traction flow deposit division (Ⅱ), and an upper suspension deposit division (Ⅲ). Our results show that: ① divisionⅠis composed of fine-grained sandstone and silty sandstone with no obvious separation of grain-size in different bed thickness; ② fine-grained sandy siltstone is very poorly developed, thus, the grain-size break between divisionⅠand divisionⅡwas occurred; ③ perfect divisionⅡincludes two series of cross beddings, one is parallel and quasi-planar and combined-flow-ripple lamination and small-scale hummocky cross stratification, the other is unidirectional and bi-directional cross lamination and parallel lamination; and ④ micrites in division Ⅲ exhibit lenticular thin bedding with irregular surface at the bottom. Compared with the previous research on turbidity currents deposition, these results suggest that: ① divisionⅠcould be the product of high density depletive flow with high suspended-fallout rate; ② divisionⅡmay be formed by the processes which is dominated by internal-waves and internal tides; ③ division Ⅲ may be formed by a complex process involving both vertical setting and slow lateral advection; and ④ the turbidity currents while depositing can be viewed as bipartite flows.

Abstract:The early Paleozoic sedimentary basins in middle-upper Yangtze region were mainly cratonic-marine basin (∈-O2) and the back-bulge basin which developed above the craton basin (O3-S).Due to the constraints of the dominative factors such as the regional tectonics, paleoclimate and the eustatic sea level change and so on, the sedimentary environments in favor of the formation of hydrocarbon source rocks were formed, meanwhile the physical foundation for the generation and reservoir of the petroleum and gas hydrocarbon accumulation was also laid. Early Cambrian, the sedimentary environment of the middle and upper Yangtze region mainly appeared as the neritic environment, the substance Phosphorus brought by the ascending currents and stably distributed black shale were all deposited, the stratum of the Meishucun Formation and Qiongzhusi Formation were the representatives. From Middle-Late Ordovician to Early Silurian, the sedimentary environment of the back-bulge basin was the limited neritic environment, where formed the hydrocarbon source rocks, which were represented by the black shale of the late Ordovician’s Wufeng Formation and the Early Silurian’s Longmaxi Formation. The favorable facies belt of the above-mentioned hydrocarbon source rocks taking on the planar distribution in the middle-upper Yangtze region, were the hydrocarbon-rich depositional areas, and also were the major and first choice areas of carrying out basic geological survey and oil and gas exploration in the Early Paleozoic marine stratum in the Yangtze region.

Abstract:The Upper Carboniferous Taiyuan Formation is a characteristic coal-bearing measure interbedded with terrigenous siliciclastic and carbonate rock in the Shenmu Gasfield of northeastern Ordos Basin, central China. Recent exploration testified its good potential for next gas development. To offer guidance for Taiyuan Formation exploitation in this gas field and exploration in Ordos basin, the strata assemblages, sedimentary characteristics, environment evolution, sandbody width and sedimentary facies control on reservoirs of Taiyuan Formation are investigated based on analysis of well-logging, mud-logging, routine thin-secition, cast thin-section, routine petrophysical property and grain size and combined with core description. The Taiyuan Formation develops three types of strata assemblages, including clastic rock type, limestone type and interbed of clastic rock and limestone type. The color, grain size, composition, texture, sedimentary structure, lithofaices, log facies, inclusion and depositional succession of Taiyuan Formation indicate it deposited from tide-dominated delta and low-energetic carbonate platform, mostly from environment of deltaic plain distributary channels and interdistribuarty swales, deltaic front distal bars and underwater interdistribuary bay, and lime tidal flat and lime-mud tidal flat. The lower portion of Taiyuan Formation (the Second Member of Taiyuan Formation, briefly SMTF) is mainly controlled by deltaic plain deposits, of which distributary channel sandbody is wide spread but has relatively narrow width(7.1-131.9m). The upper portion(the First Member of Taiyuan Formation, briefly FMTF) deposited from deltaic front and carbonate tidal flat. This implies the Taiyuan Formation had passed through a transgressive process with gradually water-depth deepening and/or a depositional process with gradually clast support decreasing. The interbed of clastic rock and carbonate rock in the FMTF reflects an oscillating process from water-depth deepening to shallowing and/or a kind of cycling insufficiency of terrigenous clastic supply. The reservoirs mostly exist in the medium-and coarse-grained sandstones deposited from high-energetic deltaic plain distributary channels in the SMTF.

Abstract:Abstract: Diagenesis control the porosity evolution, with symbolic meaning, it is very important for the exploration of the oil and gas. The carbonate of middle-lower Permian of Wuwei-Chaohui area in Anhui province widely and well developed, and the organic matter is very rich. So many years the work is focused on strata, paleontology and sedimentary facies, little on diagenesis. Microscopic examination shows that the studying area mainly develop dissolution, dedolomitization, pressure solution, tectonic rupture four types of destructive diageneses and micritization, compaction, cementation, dolomitization, silicification, recrystallization six types of Constructive diageneses. Compared with the C-O isotope analysis results, this area included marine(shallow marine platform and deep sea slope), meteoric(vadose and phreatic zone) and burial mainly three types of diagenetic environment, developing different diagenesis respectively. Marine environment: mainly micritization(shallow marine platform) and the first type of silicification(deep sea slope); Burial environment: mainly compaction, pressure solution, dolomitization, the third type of selective silification and late recrystallization; Meteoric environment: cementation(including drusy isopachous rim cement, drusy cement and coaxial accretion cement, belonging to phreatic zone, gravity-type cement and crescent cement, belonging to vadose zone), dissolution, early recrystallization, dedolomitization and the second type of silicification. Except for rich organic matter, the studying area has high porosity, the highest is up to 2%-5%, mainly developed in the pressure solution of Chuanshan and Qixia Formation, also in the silicon members and silicon highly contained limestone of Qixia Formation, excellent connectivity and rich organic matter make it the ideal place for generation, storage and migration of the gas and oil. Therefore, there is great theoretical and strategical significance for the further geological study, predicting and explorating the gas and oil in studying the diagenesis of the carbonate of middle-lower Permian of Wuwei-Chaohui area in Anhui province.

Abstract:The Santanghu Basin, being part of the northern Xingjiang province, was in the state of relaxant and collapsing tectonic environments after integral collision in the late Carboniferous, and most of the volcanic rocks are basic. It suffered compression from other plates at the end of late Carboniferous and was exposed to weathering and erosion. Weathering and fracturing alteration made the Paleozoic volcanic rocks become favorable reservoirs and rocks did not suffered these processes are unfavorable. Physical properties of various volcanic rocks enlarged and become favorable reservoirs after weathering and erosion. These spaces of the reservoirs mainly are secondary dissolution pores and fractures exhibiting a feature of double peak. The five layered structure is established for the volcanic erosion integrate, and indenting methods are brought forward. Different types of porosities and rock structures in various layers of the erosion are different. The corrosion zone and disintegrate zone are more favorable in the five, and the thickness of the whole erosion can reach 380m by far. And when the erosion controlled by faults with low angle fractures, it will become more favorable and thicker. The erosion mostly occurred at high place of paleo-geomorphology and slope, and along with the fault it developed better. These studies changed the concept that the Paleozoic volcanic rocks are not profitable for it’s strongly diagenesis and poor reservoirs, enlarging the exploration realm for oil and gas and will be important scientific significance for volcanic erosion exploration. Finally, weathering volcanic rocks existing in the Paleozoic strata in the western and central basins of China, and this will be a new petroleum exploration prospect for the future.

Abstract:The wettability of minerals constrains the characteristics of micro-flow and distribution of fluids in reservoirs. The difference of wettability between oil and water lead to different types fluid inclusions formed in reservoirs. Experimental analysis of mineral surfaces show that quartz is distinct oleophilic, but the wettability of calcite is no obvious difference between water and crude oil. Gasoline extend completely on quartz and calcite, it means that all minerals are oleophilic for light oil. Experiments of synthetic hydrocarbon-bearing inclusions and analysis of fluid inclusions from natural reservoir indicate that wettability have great effect on forming of fluid inclusions and in reservoir. Results of experiments proved that it have significantly effect on mineral crystal growth, diagenesis be suppressed, and the number of hydrocarbon-bearing inclusions decrease during accumulation of light oil. However, it does not remarkable effect on diagensis and forming of inclusions during emplacing of heavy oil. Overall, oils restrain quartz much more than calcite during accumulation of oil and gas because quartz is more oleophilic than calcite. So, it is always more hydrocarbon-bearing inclusions in calcite than quartz in same reservoir.

Abstract:There are well outcrop and full stratigraphic sequence of Nanhua System in Changyang area, Western Hubei province, mainly including Liantuo Formation, Nantuo Formation and small Gucheng Formation, Datangpo Formation (only in Gucheng area,Changyang county).The clastic rocks of Liantuo Formation formed in river or estuary environment,relatively thicker in South area than North area, vertical combination of lithology can be obviously divided into three sections. Gucheng Formation was typical glacial rocks, which corresponds to Sturtian glaciation. Datangpo Formation deposited in transitional facies during interglaciation. Nantuo Formation was the most developed and important moraine stratum, which corresponds to Marinoan Glaciation, little change in lithology and thicker in Southwest than Northeast. The value of CIA is varies between 52.52~55.80 in Nantuo Formation, indicates the rfigid -arid and low chemical weathering environment. The value of CIA is 68.14 at bottomn of Liantuo Formation, 61.61~64.57 in the lower part and 55.03～59.80 in the upper part, reflect the warm-damp and medium chemical weathering, the warm-arid and low chemical weathering, the rfigid- arid and low chemical weathering environment respectively. The value of SiO2/Al2O3 is varies between 2.13~5.10 in Liantuo Formation, Lower than the value of SiO2/Al2O3 (4.47~5.16 ) in Nantuo Formation. The value of FeO/Fe2O3 is varies between 0.16~0.49 in Liantuo Formation, Lower than the value of FeO/Fe2O3 (1.96~3.11) in Nantuo Formation. These differences demonstrates that the Nantuo Formation formed in frigid-arid and lower chemical weathering environment, but the Liantuo Formation formed in relatively warm and higher chemical weathering environment. These results show that the Nanhua System in study area experienced sedimentary environmental change,ie warm-humid or warm-dry and low-medium chemical weathering in interglaciation, to cold-dry and low chemical weathering in interglaciation, and to cold-dry and low chemical weathering in glaciation.

Abstract:The Ordos Cretaceous Basin is located at western area, a arid-semiarid area. Its south section and north section is covered by loess and desert, respectively. Chemical compositions of groundwater are prominently different regionally. In the north, freshwater dominates the groundwater, but in the south, brackish water does. 8 groups of hydrochemical and isotopic samples were collected from deep groundwater (more than 400 m depth) in this basin. Results of T and 14C show that groundwater residence times are within 20343 years, and are not polluted by human being. Based on Cl concentrations and 36Cl of groundwater, influences of evaporation on the recharge of precipitation and the Cl concentrations of groundwater were discussed. This study shows that all of the evaporation and the dissolution of stratum Cl have magnitude effects on the Cl concentrations of groundwater. The groundwater in the desert section was evaporated by 29.9-63.0 times in comparison with precipitation during its recharge, which provided more than 21.3-45.3 mg/L of Cl to the groundwater. In the loess section, the groundwater was evaporated by 266.0-523.7 times, with 191.5-377.0 mg/L of Cl derived from evaporation.

Abstract:The H and O isotope compositions of water from the Yellow River were investigated in this study. The samples were collected at 24 hydrological stations along the mainstream of the Yellow River, from the source region to the Bohai Sea, during July 2005. The δD and δ18O values of water samples vary from -91~ -44‰ and -12.4~ -4.2‰ respectively. The δD and δ18O values both increased gradually from the upper reaches to the lower reaches, except for the sample from No. 1 station. The correlation between δD and δ18O follow an equation of δD=5.69δ18O-15.51. The slope of this equation (5.69) is lower than the slope of meteoric water line for the Yellow River basin (δD=6.71δ18O-5.96), and much smaller than that of meteoric water line in China (δD=7.9δ18O+8.2). It is infered that the δD and δ18O value is mainly affected by by the arid natural environment of the Yellow River. When precipitation fell to the surface, the mount of runoff is greatly reduced by dams, industrial and agricultural water. The evaporation of the Yellow River itself and water circulation use for a long time cause further evaporation. At the same time the δD values variation of the Yellow River were discussed, indicating that the values reflect the hydrogen and oxygen isotopic composition characteristics of the Yellow River water impacted by regional environment, trends in precipitation clouds in the migration process and participation degree of regional water vapor circulation.