Abstract:Abstract：Seismic Profile shows that the Tarim Basin has experienced a violin-style evolutionary process, which has led to the formation of the three-layer (fault subsidence－depression“ structure: (1) Sinian “fault subsidence” and Paleozoic－Triassic “depression”；(2) Jurassic “fault subsidence” and Cretaceous “depression”; (3) Paleogene “fault subsidence” and Neogene "depression”. The fault subsidence and the depression resulted respectively from the pull-apart and the squeezing stress field, and the variation of such a stress field was caused by the subduction dip angle variation of the neighboring ocean crust plate from small to large. The polycyclic movement of the earth's crust led to the repeated tectonic-sedimentary evolution and produced quite a few oil-generating－oil-bearing－covering assemblages which formed oil-gas accumulations characterized by varied fields and varieties of trap styles. From Sinian through Paleozoic, Mesozoic to Cenozoic, basins with the fault subsidence－depression" structure were all likely to have geological conditions favorable for the formation of oil-gas accumulations.

Abstract:Abstract：There has long existed considerable controversy concerning the epoch and stratigraphic division of Banxi Group. Based on restudying the sedimentary sequence and evolution of Banxi Group in Xiushan-Fanjingshan area, the authors performed the crystal tuff SHRIMP zircon U-Pb dating for Hongzixi Formation of Banxi Group in Xiushan area. The result suggests that the expansion of the early Banxi basin ended at about 790 Ma, followed immediately by the quick infilling and differential uplifting stage. The deposition epoch of Banxi Group in Xiushan-Fanjingshan area corresponded to that of the lower part of Banxi Group in western Hunan and that of Xiajiang Group in eastern Guizhou, with the deposition duration being between 820Ma and 790Ma. It was the early infilling of the rift basin under the background of the break-up of Rodinia supercontinent in middle Neoproterozoic.

Abstract:Abstract：Based on field geology, petrographic characteristics, spatial and temporal distribution and isotopic dating of the Late Paleozoic-Early Mesozoic intrusions in the Qimantage Corridor of the East Kunlun orogenic belt, the authors have recognized five tectono-magmatic stages and five intrusive belts. Magmatism in this area can be divided into the Early-Middle Permian, Late Permian-Middle Triassic, Middle Triassic, Late Triassic and Late Triassic-Early Jurassic stages. In the Early-Middle Permian stage, such assemblages as granodiorite + monzogranine + porphyroid monzogranite, quartz-diorite + porphyroid quartz-diorite and diorite + quartz-diorite were produced. The monzogranite + porphyroid monzogranite + syenogranite assemblage was formed in the Late Permian-Mmiddle Triassic period, the diorite + quartz-diorite + tonalite + granodiorite assemblage was emplaced in the Middle Triassic period, and the Late Triassic intrusions were composed of the quartz-monzodiorite + granodiorite + porphyroid monzogranite + syenogranite assemblage. The representative intrusion assemblage produced in the Late Triassic- Early Jurassic period is the quartz-monzonite + porphyroid syenogranite + alkali feldspar granite. These igneous assemblages are regularly distributed in the corridor and seem to be the key to revealing the tectonic evolution of the East Kunlun orogenic belt.

Abstract:Abstract：Based on the biostratigraphic study of graptolites near the Lower/Middle Ordovician boundary, the authors selected five typical stratigraphic section in such Ordovician sedimentary facies of South China as platform facies, basin facies and the transitional facies between the above two facies to conduct graphic correlation of the graptolite faunae near the Lower/Middle Ordovician boundary. The results shed further light on the duration of graptolite faunae near the Lower/Middle Ordovician boundary in South China and the precise correlation of graptolite faunae in different facies, thus laying a foundation for the precise stratigraphic correlation of different facies.

Abstract:Abstract：There exist many gas formations in the Paleozoic strata of Shenmu-Shuangshan area within eastern Ordos Basin. Horizontal and vertical variations in these formations are complex. In order to make an accurate evaluation of the sizes and characteristics of the gas formations, this paper deals with the division of the formation on the basis of the definition of the stratigraphic unit in combination with the logging and geological data. Logging and geological features of the gas formation and the index horizon as well as advantages and shortcomings of applying logging data in the division of gas formations are also discussed in detail.

Abstract:Abstract：Based on field geological survey and an analysis of such environmental indicators as grain sizes, magnetic susceptibility and carbonate content as well as ESR and U-series ages, this paper discusses the variation of the depositional environment in the Bangrong Formation during late Pleistocene. The analytical results show that the Peiku Co paleolake underwent a whole process of lake evolution：the initial shallow lake period and the development of the deep lake and the shrinkage into the shallow lake. During 127~15 ka B.P. in Late Pleistocene, the basin evolved into the strong rift stage. Being warm and humid,the water table of the lake rose, and the paleolake evolved into the shallow lake stage during 127~56 ka B.P. The paleolake went into the deep lake stage with the surface of paleolake wave rising during 56~31 ka B.P. The paleolake shrank into the shallow lake stage during 31~15 ka B.P. The emergence of freeze-thaw fold may suggest that this region went into the ice-border period.

Abstract:Abstract：There exist Upper Triassic Riganpeicuo Formation, Tumengela Formation, Xiaochaka Formation and Nadigangri Formation in Qiangtang basin, with the first two formations distributed in the southern part whereas the last two distributed in the northern part of Qiangtang depression. Based on a detailed comparative study of the oil-gas resource potential in major sedimentary basins of the Qinghai-Tibet Plateau, the authors analyzed the paleontology, lithologic assemblage, sedimentary sequence, contact relationship and chronostratigraphic features. The results show that Nadigangri Formation, Riganpeicuo Formation and Tumengela Formation occurred mainly during the formation of the rift basin in Late Triassic Norian and Rhaetian periods, whereas the Xiaochaka Formation was generated from Carnian to early Norian periods, showing comparative correlation with Nadigangri Formation, Riganpeicuo Formation and Tumengela Formation.

Abstract:Abstract：Based on theories and techniques of high-solution sequence stratigraphy and reservoir geology, the authors made a synthetic study of sequence stratigraphy, reservoir characteristics and the control factors of the lower subsection of the 2nd Member of Shahejie Formation (Es22) in Shanghe area by such means as drill core observation, slice identification, property analysis of drill core, logging curve interpretation and mercury-injection analysis, with the purpose of detecting the distribution regularity, the properties and the control factors of Shanghe sandbodies in Huimin sag. It is found that the Es22 could be divided into 3 middle base-level cycles. Sandstone reservoirs with relatively good properties occurred mainly in the early stage of the ascending middle base-level cycle and the late stage of the descending middle base-level cycle, and that the properties of sandstone reservoirs in the descending middle base-level cycle are commonly superior to those of the ascending middle base-level cycle. The following conclusions could be drawn： the properties of the reservoirs are closely related to sedimentary microfacies, i.e., reservoirs in subaqueous distributary channel sandbodies and bayou sandbars have the best properties, but with poor inhomogeneity; far sandbars and front sheet sandstone have relatively inferior properties, and beach-sandstone and interdistributary bay sandstone with strongest inhomogeneity have the worst properties. Planar distribution and inhomogeneity of sandbody reservoirs are mainly controlled by types and distribution of sedimentary microfacies. Therefore, the transference and evolution of the sedimentary facies belt and the vertical inhomogeneity of the reservoirs are all controlled by ascending and descending fluctuation of the base-level. As a result, spatial distribution and inhomogeneity of reservoirs are under the control of ascending and descending fluctuation of base-level cycles.

Abstract:Abstract：The Chepaizi-Mosuowan plaeouplift belt is located in central Junggar basin. During its main development period, there existed two depressions, i.e., Changji depression in the south and western Well Pen 1 depression in the north, with the distribution of Cretaceous, Jurassic and Paleogene source rocks. Recently, the Yongjin oilfield was discovered in the southern part of the uplift belt, whose target bed is Jurassic Toutunhe Formation, Sangonghe Formation, Xishanyao Formation and Cretaceous Tugulu Group. In the northern part, Zhengshacun, Shawodi and Mosuowan are very favorable oil-bearing structural zones, whose target bed is Sangonghe Formation. In order to determine the oil source correlations and reveal the uplift effect on the hydrocarbon accumulation process, the authors analyzed sources of differential types of oils and, on the basis of the investigations into fluid inclusions, nitrogen compounds and the evolution of source rocks, probed into the hydrocarbon accumulation process. In combination with geological conditions, it is also found that the formation and evolution of Chemo plaeouplift control the characteristics of oil sources, reservoir distribution and accumulation process. The results indicate that geochemical characteristics of crude oils are somewhat different in different structural belts or even in different layers of the same structural belt. According to the biomarker parameters of saturated and aromatic hydrocarbons, the crude oils can be divided into five types, which are to some extent different from each other in distribution, sources and locations of hydrocarbon kitchens. The formation and evolution of Chemo plaeouplift, the distribution of the hydrocarbon depression, and the maturity evolution of main source rocks have determined the locations and transformation of hydrocarbon kitchens in different oil-bearing structural belts or oil fields.

Abstract:Abstract：The Liguifu tungsten-tin polymetallic deposit occurs in the east of Dupangling granite, being mainly of the greisen-quartz vein type. The precise Re-Os isotope dating of molybdenite from the ore shows that the isochron age is (211.9±6.4)Ma (n=7，MSWD=4.1), and the weighted average of model ages is (213.3±2.9) Ma (MSWD=4.0). The isochron age suggests that mineralization took place in the Indo-Chinese epoch, and the result demonstrates that Early-Mesozoic tungsten-tin polymetallic mineralization did happen in Dupangling area.

Abstract:Abstract：On the basis of the third time prognostic data of China's coal reserves and through a systematic analysis of the distribution, buried depth and classification of discovered coal reserves and prognostic coal reserves, this paper points out that there exist 68.489 billion tons of economic recoverable coal reserves, 228.297 billion tons of unoccupied discovered coal reserves and 4552.104 billion tons of prognostic coal reserves. These data show great potential of coal resources in China. Nevertheless, the reliable coal resources that are buried less than 1000 m and can be used in the near future are only 916.91 billion tons. Therefore we have to re-understand the advantages of coal resources in China scientifically and objectively and make China's national energy policy reasonable so as to ensure the security of China's coal energy.

Abstract:Abstract：Located in southeastern Da Hinggan Ling Yanshannian metallogenic belt, the Sandaowanzi gold deposit is a quartz vein type gold deposit. Based on geological characteristics, mineral features, ore-forming periods, fluid inclusions and S, H, O isotope compositions, the authors have reached the following conclusions： calaverite is the main gold mineral; δ34S values of pyrite range from －1.1‰ to 1.7‰，showing isotopic characteristics of mantle-derived sulfur; δ18O values of ore-forming fluids responsible for the formation of quartz are in the range of 15.3‰～－9.9‰, δD V-SMOW values of inclusion fluids of the quartz vary between －110‰ and－85‰; meteoric water is dominated; the homogenization temperatures are from 181 to 267℃, and salinities from 15.6% to 16.9% (Nacl eqv.); the ore-forming pressure is 4 Mpa; and the ore-forming depth is around 0.4km. The Sandaowanzi gold deposit is hence a mesothermal－epithermal gold deposit.

Abstract:Abstract：The existence of rich organic matter constitutes one of the notable features of the Mayuan lead-zinc deposit in Shaanxi Province. In addition to the asphalt that can be identified by naked eyes and microscope, there occurs extremely abundant scattered organic matter whose composition needs to be analyzed by means of organic chemistry. Based on a microsection identification of rocks and minerals, an analysis of content and isotopes of the organic matter, and chromatography of saturated hydrocarbon gas, the author revealed the modes of occurrence and composition of organic matter in rocks, and concluded that the types of asphalt are syngenetic-diagenetic asphalt, epigenetic (remolded) asphalt and supergene asphalt. On the basis of such biomarkers as n-alkanes, pristane and phytane, the composition of the organic matter can be determined, the ore-forming environment can be analyzed, and the relationship between the organic matter and lead-zinc can be detected.

Abstract:Abstract： The well-known Huangshan-Jing'erquan Cu-Ni metallogenic belt in East Tianshan Mountains has lots of genetically similar copper-nickel deposits. Based on field investigation, the authors made electron microprobe analysis of the components and carried out a detailed study of the mineral composition of the copper-nickel ore deposits. The ore minerals can be classified into Fe-S series, Fe-Cu-S series, Fe-Co-Ni-S series, Fe-Co-Ni-As series, Fe-Co-Ni-As-S series and telluride. According to characteristics of mineral associations, the ore-forming process is divided into the magmatic liquation ore-forming period, the magmatic hydrothermal ore-forming period and the epigenetic weathering period. Based on calculating the crystal-chemical formula of these mineral compositions, this paper describes the modes of occurrence and geneses of these minerals. Zircon U-Pb age of (285 ± 1.2) Ma for Xiangshan rocks and and Re-Os isochron age of (298 ± 7.1)Ma for pentlandite suggest the consistency between the rock-forming and the ore-forming ages.

Abstract:Abstract：A borehole was drilled at Zhoulao Town in Jianghan plain, and then ten gravel layers in core sediments were analyzed in order to study heavy mineral components and distribution characteristics of the fillings. The results show that the ten gravel layers can be divided into three mineral stages from bottom to top. A comparative study of the stable and unstable heavy minerals of the three stages has revealed that the variation characteristics are as follows: sediments of stage 1 and 2 are composed mainly of distal materials with a small amount of proximal materials, whereas the major sediments of stage 3 are distal materials mixed with a certain amount of proximal materials. Based on core lithology and gravel contents as well as Quaternary lithofacies features of Jianghan plain, the authors hold that at the depth of 112.30～109.05 m in the borehole (1.17-1.12 Ma.B.P., namely stage 3), the sedimentary environment changed remarkably, and the water system of the Jianghan plain underwent considerable variation, which finally led to the formation of the Three Gorges on the Yangtze River.

Abstract:Abstract：With the rapid development of China's resource energy industry, the scheme of burning crude oil to produce steam and achieve the heavy oil thermal process needs modification. Meanwhile, the utilization of folium or edge water to drive heavy oil reservoir disagrees with the thermal process, the electric heating leads to considerable electrical consumption, and the low injection water temperature causes the decrease of oil layer temperature and the increase of crude oil viscidity. The prolonged temperature difference leads to the breaking up of reservoir pore throat cement and framework minerals. To improve the high-capacity channel communication, the authors put forward some suggestions concerning geothermal oil recovery. The broad-sense abundant geothermal resources and existing injection water technique equipment are used, the deep-seated high temperature liquid （oil-gas-water mixture）draws geothermal warming flowing layer to transit heat upward, decrease viscidity and increase fluidity. Layers different in temperature offer geothermal fountain. Practicability of the process is analyzed. Based on statistics and analysis of the temperature field variation characteristics of the Gudong oilfield, the authors have designed the flow-chart concept for geothermal oil recovery, suggested drilling the multi-branch well of the heavy oil reservoir as the injection-well at the same position of the geothermal fountain well, using free-pressure pump to inject hot liquid directly to the aimed oil layer, and making oil recovery in the surrounding wells. It is proposed that the geothermal oil recovery forerunner test should be first conducted in favorable blocks.

Abstract:Abstract：Kaolinite and montmorillonite are representative minerals of the warm-humid and cold-arid climate, respectively. A comparative study of the humic acid adsorption capability between kaolinite and montmorillonite might provide important evidence for the environmental behaviors of heavy metals in soils which are developed in different climate zones. In this study, batch adsorption experiments for humic acid were carried out with two species of clay minerals (kaolinite and montmorillonite) under different solution conditions of pH values, ionic strengths and initial concentrations of the humic acid. The aim of this study was to explore the causes responsible for the generality and diversity between kaolinite and montmorillonite in the adsorption of humic acid. Some conclusions have been reached: 1) humic acid adsorbed on both kaolinite and montorillonite gradually increases with increasing initial concentrations of humic acid and ionic strength under the condition pH=5; 2) the adsorption amount of humic acid on kaolinite and montorillonite decreases with the increasing pH value; 3) the humic acid adsorbed on kaolinite is higher than that adsorbed on montorillonite under the condition pH＜6, and things are just the opposite under the condition pH＞6, which may be related to different adsorption mechanisms of kaolinite and montmorillonite for humic acid. When pH＜6, electrostatic interaction between kaolinite and humic acid dominantes, and the ligand exchange and hydrogen bonds seem to play a minor role, while hydrogen bonds are the main adsorption mechanism for montmorillonite. When pH＞6, the main adsorption mechanisms of kaolinite and montmorillonite are hydrophobic interaction and cationic bridge, respectively.

Abstract:Abstract： In order to detect the origin and content of manganese in groundwater of the Zhujiang River Delta, the authors sampled and analyzed 352 groundwater samples and 13 surface water samples. The results show that manganese content varies from the undetected level to 8.32 mg/L in groundwater of the Zhujiang River Delta, with the average manganese content being 0.34 mg/L and the standard-exceeding rate being 49.4%. The manganese content of groundwater that exceeds the standard exists in nine cities of the Zhujiang River Delta. There exists an obvious positive correlation between the manganese content and TDS, COD, and HCO3ˉ of groundwater as well as a notable negative correlation between the manganese content and Eh of groundwater in this delta area. The distribution of manganese in groundwater is closely related to the extent of industrialization and recharge, runoff and discharge conditions of this area. Redox environment, pH condition, total dissolved solids in groundwater, property of the cover, groundwater flow conditions, and aquifer media are major factors responsible for the distribution of manganese in groundwater of the Zhujiang River Delta.

Abstract:Abstract：Steep and antithetic platy structure of rock mass and geomorphology of the longitudinal valley in the dam site area cause wide-range toppling deformation on the cross-strait slope. Aimed at solving problems of toppling deformation, the authors, in the light of regional engineering geological conditions, analyzed characteristics of toppling rock mass deformation, made degree classification of toppling ruptures, established discrete element slope models for excavation and failure mechanism, and detected characteristics of the excavated slope and four developing processes of failure mechanism. There exist shear dislocation in weak toppling rock deformation, tensile deformation on layers in strong toppling rock deformation, strain-shear rupture through layers in strong toppling rock deformation and tensile fracture on very strong toppling rock rupture. The results provide a scientific basis for stability evaluation of the dip-slip body and the excavation work.

Abstract:Abstract：To provide scientific reference for shallow groundwater exploitation, this paper analyzed the effect of sedimentary environment on the distribution of shallow groundwater quality from the angle of geological history and the effect of human activity on groundwater quality evolution and on the basis of sufficient utilization of historical water quality data. The result shows that the sedimentary environment controls the spatial distribution of groundwater quality and the human activity has exerted two kinds of effects on water quality evolution, i.e., contamination and freshening by groundwater exploitation.

Abstract:Abstract：Groundwater numerical modeling on the regional scale is an important technical support for groundwater management. Based on a summarization of characteristics of regional groundwater modeling abroad, this paper describes features of regional groundwater modeling, with the regional groundwater numerical modeling for the North China plain as an example. The existent problems in regional groundwater numerical modeling are also pointed out.

Abstract:Abstract：Based on the abnomal chemical composition phenomena of underground hot water along the principal fault, this paper has advanced a new conceptual model for geothermal resource, i.e., structural trap type of geothermal resource. The structural trap type energy is stored in a relatively closed hydrogeological environment characterized by slow underground water runoff, high degree of metamorphism, complete water-rock interaction, and abundant chemical elements in dissolved rocks, thus likely to form a kind of good medical hot mineral water. The structural trap type energy has a special significance in geothermal resource exploration, and hence researchers should pay full attention to the medical treatment and health care function of underground hot water in the structural trap type energy storage.

Abstract:Abstract：The Tangshan-Qinghuangdao area is an important agro-economic tract in Hebei Province, and the safety evaluation of its soil quality has a considerable realistic significance. According to the regional topsoil geochemical data, the authors employed the single factor index method and the Nemerow synthetic index method to make soil quality assessment. The results indicate that the pollution of heavy metal elements is caused mainly by Ni, Cr, Cu and Cd. The polluted areas of heavy metal elements Ni, Cr and Cu are mainly concentrated in the border area and the northern part of Lulong, Funing and Changli counties, whereas the polluted areas of Cd heavy metal element are mainly concentrated in the western and northwest parts of Tanghai County. The environmental geochemical quality of most soils in Tangshan-Qinghuangdao area is proved to be pretty well, with no obvious pollution.

Abstract:Abstract：Based on a comparative study of major international classification proposals for mineral resources and reserves, this paper sums up current international practice and rules in this aspect. Based on an analysis of the problems and defects of the United Nations Framework Classification for Energy and Mineral Resources, the author points out the deviations of the National Standards on Solid Mineral Resources/Reserves Classification from the internationally recognized practice, with a discussion on the problems encountered during the utilization. Suggestions on the revision and perfection of China's classification standards of mineral resources and reserves are also put forward in this paper.