Abstract:In a layered lithosphere slipping system, there are many pores filled of fluid with a certain pressure. Suppose the floating force caused by the pore fluid pressure in the slipping plane is Ff, the loading weight of bedding slipping block is ST , then a new index of R ,the ratio of Ff to ST , can be given, that is very important to describe the slipping motion of the layered lithosphere being easy or difficult. Actually, shear strain of the lithosphere can outstandingly change its value. In this paper the author try to inference a dynamic equation describing the relationship between R and the shear angle (α) as the follow formula: R(α)=R0P(α)P0cosα (1) R(α)=R0cosα,\[P(α)=P0，constant pressure\] (2) According above formula(1), R(α) is positive correlation with P(α), and also is positive correlation with shear angle α. It is difficult to give the formula of describing the relationship between R(α) and α, but the pore fluid keeping its pressure to be a constant is common case in the shearing process, that is P(α)= P0. P0 replaces P(α) of above formula(1), the above formula(2) can be gotten, and then R(α)—α diagram of constant pressure shearing process can be drawn, in which the law can be discovered as follow: in a constant pressure shear strain process, when R0>0, R(α) increase with α; as shear angle α increasing at a certain value, R(α) exceed 1 rapidly; and the move R0 is, the less the α is for R(α)>1; otherwise, the more the α is. R(α)>1 means the bedding slipping block is totally supported by pore fluid pressure. This law reveals a possible outbreaking mechanism of subduction—thrust nappe or detachment structure or landslide in lithosphere.

Abstract:A well preserved Changshingian radiolarian fauna was obtained from bedded siliceous limestone and interbedded siliceous shale of the Dalong Formation in Shangsi area, Guangyuan, Sichuan, South China. The radiolarian species in each sample were identified, and the individuals in 1g samples ( sieved through 300 meshes ) were counted out. In general, most of the encountered specimens are Spumellaria and Entactinaria. Neither the abundance nor the diversity of it is high. The research shows that the abundance and diversity are closely related to sea level changes of Changhsingian age at the Shangsi Section. Where abundance and diversity reached higher values, the sea level would have peaked ( marine flooding surfaces ). The abundance and diversity of radiolarians from the early Changhsingian is greater than that of the late Changhsingian age, which coincides with the opinion that the marine water was deeper in the early Changhsingian than that in the late Changhsingian. Furthermore, foraminifer and radiolarian abundance showed a good negative correlation which may be caused by their different living habits and changes of water depth. Analysis shows that: the development of the Late Permian radiolarian fauna of the Shangsi Section, may result from changes of water depth.

Abstract:The Qingdong sag of the Jiyang depression is a Cenozoic faulted basin in the southern Bohai Bay basin. The sag contains nearly EW，NW and NNE striking fault systems. The NW and NNE striking faults belong to basement faults respectively resulting from foreland deformation in the Indosinian period and the Tancheng—Lujiang(Tan Lu) sinistral faulting in Late Jurassic. The sag was under NS extension and undergone intense rifting during the Paleogene, leading to formation of the EW faults. The two sets of basement faults reactivated by a way of oblique extension under the NS extension. The NW and NNE striking basement faults have sinistral and dextral movement respectively. Reactivity of the NW striking basement faults predominate in the Qingdong sag during the Paleogene，which had more intensive activities and controlled the NW to SE sedimentary framework during the early rifting stage, then replaced by large numbers of EW faults and resultant EW sedimentary framework in the later rifting stage. However，the larger WNW striking faults with lower strength and in more favorable extended direction have the sustained and intensive activities. It is for the low strength that the large scale Qingdong 4 fault zone and Tan Lu fault zone also showed strong and sustained activities. Moreover，they present left or right en echelon arrangement on horizontal and flower liking structure on profile as being with large proportion of strike slip movement，displaying the large scale basement reactivated features. After more detail studies，Reactivity methods of the basement faults can be classed into three types，such as the direct activity，formation of new en echelon faults and direct activity plus propagating into EW faults. It can be seen that basement faults have important effect in the evolution and distribution of fault systems and sedimentary filling characteristic in a basin.

Abstract:Soft sediment deformation structures form due to disturbance of sediments during or after deposition, consolidation and burial. As one kind of widespread sedimentary structure, many studies focused on its classification and genesis. According to the genesis mechanism, Soft sediment deformation structurescan be classified as: (1) load structures, (2) convolute lamination and bedding, (3) deformed cross bedding, (4) slump sheets, (5) water escape structures and sediment injection structures, (6) collapse structures, (7) structures of biological and chemical origin. As an important and special structure, sesimite can be classified as syndepositional，penecontemporaneous and epigenetic deformationstructures．Many factors can act as the triggers for the soft sediment deformation structure, but the earthquake inducedliquefaction is the most important one. The trigger and mechanism of the soft sediment deformation are quite complex and can be identified by a process including faces analysis, trigger assessment and criterion assessment. Due to its important significance on many areas, the future study of the soft sediment deformation will be still focused on the classification and identification of the mechanism. The application on the civil geological engineering is also an aspect for many geologists. With the oil exploration from shallow water to deep water, it is another studying area to find the oil reservoir related with soft sediment deformation structures.

Abstract:According to the characteristics of the climate change, the red beds from the Es4-1—Ek1 (the Lower Sub-Member of the 4th Member, Shahejie Formation, to the 1st Member, Kongdian Formation, Eocene) in Dongying Depression are availably divided, which have not been divided for a long time because of lacking referential fossils. The relative climate change is recovered based on logging data in combination with the relative content of Ephedripites. At first, according to the relative content of Ephedripites, the depth section of the inflection point of the climate change is defined. Then, based on continuous clay mineral contents which are determined by natural gamma ray spectrometry log data or conventional log data, the concrete depth of the inflection point of the climate is thereby defined, which is recognized as the boundary in the red beds. By the model which from standard well log data, red beds in other new wells nearby can also be divided. The scientific and rational method has been proved by afterward exploration. This method provides a new thought in dividing the fossil barren beds.

Abstract:Dee pwater sedimentary basins of passive margins are a hot field in petroleum exploration and sedimentology research. Based on the study of Niger Delta basin and Baiyun sag, Pearl River Mouth basin, making use of high resolution 3 D seismic data, the deepwater gravity flowdepositional elementsanddeepwater depositional systemsare discussed and three conclusions are made: (1) Deep water gravity flow depositional systems in different basins vary in general distribution, however they are all composed of basic depositional elements which are mass transport deposits, submarine channel, and lobe. (2) Due to the differences in gravity flow supply, continental slope topography, equilibrium profile, accommodation, and deposition process, there are significant differences in the deep water gravity flow depositional systems and their system stack styles in passive margin basins. (3) When the deep water gravity flow depositional elements are identified and characterized, the Main controlling factors should be taken into account for the deepwater gravity flow depositional system. It is unrealistic to accurately summarize and predict the gravity flow depositional system with any single model.

Abstract:The mid Neoproterozoic Danzhou Group outcropped across the Jiuwandashan Mountains and the Yuecheng Mountains in Northern Guangxi. The Danzhou Group, which consisted of low metamorphic or normal sedimentation inter bedded with igneous rocks, overlay the Metamorphite series of the Sibao Group with unconfomity; and underlay the Nanhua glacial deposition with conformity. Writers characterized the sedimentary facies and depositional sequences of the Danzhou Group at the Huangjin section, Luocheng County, northern Guangxi. From the bottom to the top, the Baizhu Formation and Hetong Formation were composed of five kinds of facies, alluvial—fluvial facies (immigrating beach facies), delta facies, shallow shelf facies, carbonate ramp (or platform), deep shelf facies (or starved basin facies),respectively. The Gongdong Formation contained deep water turbidite and shallow shelf facies from bottom to top, and lately developed delta facies. Based on the comprehensive analysis of sedimentary facies and sedimentary succession, and combined with depositional record of volcanic activity, it is believed that the occurence of the bimodal large igneous rock provinces (LIPs) which accompanied with the onset of sedimentary basin, transgression overlap and starve deposition in early stage, and differential subsidence and quickly filling in late stage, and episodic volcano—magmatic activity with the basin evolution, were all contradictory to the arc—continent collision model. The Danzhou Group and its equivalences were an early filling succession of rift basin, and the phases of the basin evolution should be a sedimentary response to mantle plume episodic activities.

Abstract:The Luzhenguan Group is an important part of the North Huaiyang low grade metamorphic belt (NH), whose evolution process is critical for offering evidences for deep subduction of the ultra pressure rocks and getting integrated history of the Dabie Mountains. In this work, some biotite two feldspar gneisses with garnet and garnet—biotite gneisses were collected in Niujiaochong and Yu’erjie, Huoshan County, for electronic analysis. Using the garnet—biotite—plagioclase—quartz geobarometry, metamorphic pressure between 1.89~1.99 GPa and the average 1.94 GPa was gained. Based on average density of the rocks located in upper and middle crust of the Dabie Mountains, a conclusion is drawn that the Luzhenguan Group once subducted into 64.7 km in depth. This conclusion suggests that the North Huaiyang belt experienced deeper subduction and supports that the suture zone between the North China block and the South China locates in north of the North Huaiyang belt.

Abstract:The Pobei intrusive rocks, which is located in the northeastern part of the Tarim plate, is composed of intrusions of 5 stages. The olivine gabbronorite intrusions, which formed during the second stage of the magmatism, are mainly composed of olivine gabbronorites. In some places, there are fragmentary gabbronorites or anorthosites. All the rocks are calc alkalic series, while the composition of clinopyroxenes shows that the parent magma is tholeiitic. The transformations of magmatic evolution and rock chemical series are attributed to contamination. Data of Sr—Nd isotopes show that the magma of the olivine gabbronorite intrusions had undergone 138% to 315% contamination of the Gudongjing Group, Changchengian System, Mesoproterozoic. The MgO value of primary magma is 731%, which ranges in basaltic magma. The abundance of TiO2, Na2O, K2O, rare earth elements and large ion lithophile elements of the rocks is lower. The εNd(t) values are during +254 and +281 except one sample. These characteristics suggest that the magma source is depleted continental lithospheric mantle. The magma crystallized in a stable situation, while the crystallization temperature is about 1070℃. The cumulate texture and laminar structure result from nonequilibrium fractional crystallization in some places. Low degree partial melting from continental lithospheric mantle source region results in the lack of sulfur for primary magma. At the same time, the fractional crystallization of magma was too weak. All these factors make it impossible for the olivine gabbronorite intrusions to form Cu—Ni sulfide deposit.

Abstract:Rare earth element and trace element of molybdenite in the Bangpu Mo (Cu) deposit, Maizhokunggar, Xizang (Tibet), were analyzed by high sensitive inductively Coupled Plasma Mass Spectrometry in this paper. The testing results indicated that rare earth element in molybdenite had the distribution pattern of LREE enrichment and the fractionation in both light rare earth element and heavy rare earth element were obvious. Eu and Ce negative anomalies exist in different degree in the molybdenite. The Eu negative anomaly in molybdenite maybe inherit the characteristics of Eu negative anomaly of the ore forming fluid itself and the Ce negative anomaly reflected that the ore forming fluid were of stronger oxidization property. The high contents of Cu, Pb, Zn and W in the molybdenite revealed that the ore forming fluid was riched in ore forming elements itself. Depletion of high strong field element and the Hf/Sm, Nb/La, Th/La ratios less than 1 suggested that the ore formign fluid was a Cl riched type fluid. Ratios of Y/Ho and Zr/Hf varied in a narrow range indicated that source of the ore forming fluid in the main metallogenic stage was single and stable and had no other fluid injecting.

Abstract:Using interpretation results of high precision three dimensional seismic data, the lateral transitional zone associated with faults of different occurrence are analyzed, which are from different tectonic movement since the Mesozoic in southern Jiyang Depression, Bohai Bay Basin. Research shows that the lateral transitional zone in NNE direction is composed of lateral compressive fold and lateral fault ramp in Indosinian movement. In Yanshanian movement, the lateral transitional zone is in NEE direction, which is assembled by the transfer fault and lateral uplift. The lateral transitional zone is NW, which is made up of the relay ramps and transfer zone in Himalayan movement. The different tectonic parts of lateral transitional zone possess unequal changes in evolution of superposition and migration respectively, creating different tectonic settings, which causes different migration and accumulation of hydrocarbon. Superimposed transitional zone can form composite zones of hydrocarbon accumulations. Migrated transitional zone can result in “sag wide oil bearing” hydrocarbon distribution.

Abstract:The formation of hydrocarbon source rocks in continental basins may be related to marine transgression. This issue is of scientific and practical significance in the theoretical study of hydrocarbon generation in continental basins, but has uncertainties. In order to improve the understanding on the issue more comprehensively and deeply, we conducted a research review, and further suggested the future directions for study. The determination of transgression is the basis for this study. Thus, we investigated the evidence supporting the transgression, which can be divided into three folds including biological, mineralogical and petrological, and geochemical. These multiple lines of evidence indicate that transgression might take place during the formation of hydrocarbon source rocks in some continental basins. The influence of transgression on the formation of the source rock is reflected in the abundance and type of organic matter, with the abundance higher and type better. In addition, it promotes the development of larger scale source rocks. In the future, we should continue to strengthen the study of finding macro and micro evidence supporting the transgression. In addition, the case study in southeastern China can provide a good complementary, where the depositional environment has a transitional change from marine, lacustrine influenced by transgression, to lacustrine. Thus a sophisticated temporal and spatial comparison can be obtained. The results will help to comprehensively and precisely understand the forming mechanism of hydrocarbon source rocks and provide information for hydrocarbon exploration

Abstract:Trace metals and their species in sediments are powerful proxies to indicate the human induced environmental changes of waters including heavy metal contamination, primary productivity and redox conditions of depositional environment. Concentrations of heavy metals in sediments from many waters have substantially increased over the past century. This revealed the elevated loading of heavy metals caused by various human activities, such as mining, smelting, sewage discharge, application of fertilizer and the combustion of coal and oil, etc. Cu, Zn, Ni, Ba and Cd are micro nutrients for phytoplankton, whose concentrations in sediments could indicate the changes in primary productivity in water. Redox sensitive elements including U, Mo, V, Cu, Cd and Mn and their ratios, such as Re/Mo, Cd/U, Th/U and V/Sc, were useful tracers for redox state of the depositional environment. It is worth noticing that these productivity and redox proxies could hardly reflect the productivity and redox conditions in waters which were strongly affected by human activities. This probably results from the anthropogenic input of these elements which might mask their authigenic and diagenetic records in sediment. Therefore, identification of the sources of trace metals is crucial in indicating past environmental changes. Several chemical and statistical methods for discriminating the sources of trace metals have been summarized, including isotopic tracer, chemical extraction, enrichment factor and principal factor analysis. Furthermore, digenesis might disturb the sediment records of trace metals and thus affect the reconstruction of environment changes of water by these metals. The application of multiple metal proxies is a promising way to properly read the sediment records and reconstruct the history of aquatic environmental changes.

Abstract:The Tarim Block is one of the main three continental blocks (plates) in China. It has typical double layers structure consisting of the Precambrian basement and Neoproterozoic to Cambrian cover. In this contribution, the authors integrated the recently published Precambrian studies of the Tarim block and have a detailed analyzing on these data. Based on the study herein, we constructed its Precambrian evolution stages, courses and its tectono magmatic—metamorphic concurrence to the global scale suppercontinent evolution. Importantly, we discussed the sedimentary and metamorphic ages of the blueschist bearing Aksu Group according to recently obtained geochronological data and the regional geology, in combination with the previous studies on the Neoproterozoic igneous rocks, we argued that the Tarim Block could assemblage to the northern side of the Australia during late Mesoproterozoic to early Neoproterozoic (1000~900 Ma). Nevertheless, the subduction along the northern side of the Tarim Block could last till to 760 Ma and during 820~760 Ma, interaction between plate subduction and the Rodinian plume resulted the intriguing magmatic—metamorphic events. This new model may shed a light on the international controversy on the Neoproterozoic evolution of the South China.

Abstract:Traditionally, the concept of biomineralization has been defined as the mineral formation by organism and further has been grouped into two types, i.e. the biologically controlled and the biologically induced biomineralizations. This broad term of biomineralization has been emended as the process by which living forms influence the precipitation of mineral materials; correspondingly, the term of biomineral has been redefined as the product of the selective uptake of elements from the local environment, and it can incorporate into functional structures under strict biological control. Correspondingly, the concept of “organomineralization” that is derived from the broad biomineralization is used to describe a mineral formation linked to non living organic substances, and the product resulted from the biomineralization is defined as the “organomineral”, i.e. refers to minerals that are affected by organics, mostly life related, but not directly produced by living cells. Thus, the chief difference between the biomineral and the organomineral is that the later can not incorporate into functional structures under strict biological control. When the biomineralization attract the attention by biologists and chemists, it becomes the research object for the further understanding of “the sophisticate chemical process within life system”; further, the biomineralization gradually becomes an attracting research field of many subjects beyond the geological field. At the same time, studies on the biomineralization result in the advances of the organomineralization. Because the organomineralization and its product, i.e., the organomineral, is volumetrically important constituent of the sedimentary rock record, is synonymous with paleontology and is potentially exciting tracer for life beyond Earth, studies on the organomineralization and its product become an important researching theme within the framework of geobiology.

Abstract:Geochronology, petrology and geochemistry were performed systematically on basic dykes in Mianning, Sichuan province. On the basis of major and trace elements patterns, basic dykes belong to tholeiitic basalt serie in lithology and have OIB (Ocean island basalts) features, which were homologous with Emeishan basalts. Trace elements tracing and Th/Hf—Ta/Hf identification diagram show that basic dykes were derived from mantle plume with little contamination. The LA ICP MS U Pb zircon data of basic dyke yields a concordant age, 256.7 4.3Ma, which may represents the rock mass crystallization time. It shows that the Mianming basic dykes were formed in the late period of Emeishan mantle plume magmatism. In addition, the dating implies that dykes experienced geological events occurred about 244Ma, which was caused by thermal erosion of magma and triggered by the Indosinian movement.

Abstract:Granitoids in the Eastern Guangdong encompass three main rock types: Dapu biotite granites,Dapu bitite K spar granites and Jiexi bitite K spar granites. Zircon LA ICP MS U Pb dating of Dapu biotite granites and Jiexi bitite K spar granites indicates similar ages of emplacement of 136.3±0.6Ma and 134.9±0.4Ma ,respectively, which belongs to Early Cretaceous but not Late Jurassic; All of these three types of rocks are rich in Si,Al, medium in alkali content, but poor in Fe, Mg, Ca,Ti and P, belong to a high K calc alkaline series, as well as a weakly peraluminous granite series. Dapu biotite granites hasδEu mid negative anomaly, slightly right inclined REE distribution pattern, forming by the partial melting of Proterozoic arenitic metasediments. Dapu bitite K spar granites and Jiexi bitite K spar granites have strongly δEu negative anomaly, seagull like REE pattern. Dapu bitite K spar granites and Jiexi bitite K spar granites are coexist closely, forming in the same time,and shows continuous variation trend in geochemistry, have similar isotopic composition, may be formed by partial melting of Proterozoic pelitic metamorphic sedimentary rocks, are the results of different evolution stage of the same magma.

Abstract:This paperanalyzed the information asymmetry problem between prediction areas and known areas faced by the mineral resource quantitative predictionand brought a comprehensive geo information quantitative prediction method limited by spatial affecting extent to deal with it, which applied in manganese ore prediction in western Guangxi and southeastern Yunnan, China.Its major steps included: (1) The spatial affecting extent of geo variant was defined with intersection of data extent, affecting extent and extent occupied by range of values of known areas, avoiding extrapolationof raw data when not occupy whole prediction areas; (2) The spatial affecting extent of prediction model was defined with intersection of geo variants that that make up the model, and model was meaninglesswhen the intersectionis null; (3) Through combinationof geo variants, a series of quantitative prediction models was built using multivariate linear regression; (4) To each prediction unit, prediction model was selected to calculateits reserve, which including most geo information and best regression effect. The procedure of prediction matched metallogenesisof prediction areas with prediction models built in known areas, which efficientlyensured the information symmetry.

Abstract:This paper presents a detailed study on morphology and geochemistry of cassiterite from the ore bearing quartz veins of the Taoxikeng tin deposit, southern Jiangxi. The cassiterite in the Taoxikeng tin deposit can be divided into three types of morphology according to their different crystallographic forms: A type cassiterite is composed of {111} pyramidal form + {110} prismatic form, B type cassiterite is composed of {111} pyramidal form + {110} prismatic form + {100} prismatic form, and C type cassiterite is composed of {111} pyramidal form + {101} pyramidal form + {110} prismatic form + {100} prismatic form. Based on previous studies, it is considered that A type and B type cassiterites should be formed at a higher temperature than C type cassiterite. For the first time, the internal structure within the cassiterite grains was observed by the cathodoluminescence (CL) imaging. We have revealed that there are two stages of crystallization of cassiterite in the Taoxikeng tin deposit. The early stage of cassiterite commonly shows a relatively weak CL brightness (black to dark grey) with the oscillatory zoning and the sector zoning, and the margin of the phase were highly corroded. The crystallographic type of the phase is responsible for A type or B type cassiterite. The late stage of cassiterite shows a relatively strong CL brightness (light grey to white) without the oscillatory zoning and the sector zoning. It occurrs either as overgrowth on the early stage of cassiterite, or as veinlet within the early stage of cassiterite. The crystallographic type of the late stage of cassiterite is responsible for C type cassiterite. The electron microprobe analysis data shows that the cassiterite in the Taoxikeng tin deposit contains high levels of FeO and Ta2O5, indicating that it should be formed at a higher temperature. It also shows high HfO2 contents with low Zr/Hf ratio, suggesting that the ore forming fluid should be derived from a highly differentiated granitic magma. The early stage of cassiterite contains higher FeO and lower In2O3 than the late stage of cassiterite, indicating that the early stage of cassiterite should be formed under a condition of higher temperature and pressure than the late stage of cassiterite. The two stages of cassiterite crystallization are considered to be related to the two stages of magmatic—hydrothermal activities in the Taoxikeng tin deposit, respectively.

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