Layer-block tectonics of Cenozoic basements and formation of intra-plate basins in Nansha micro-plate, southern South China Sea

Layer-block tectonics （LBT） concept, with the core of pluralistic geodynamic outlook and multilayer-sliding tectonic outlook, is one of new keys to study 3-dimensional solid and its 4-dimensional evolution history of global tectonic system controlled by global geodynamics system. The LBT concept is applied to study the lithospheric tectonics of the southern South China Sea （SCS）. Based on the analysis of about 30 000 km of geophysical and geological data, some layer-blocks in the Nansha micro-plate can be divided as Nansha ultra-crustal layer-block, Zengmu crustal layer-block, Nanwei （Rifleman bank）-Andu （Ardasier bank） and Liyue （Reed bank） North Palawan crustal layer-blocks, Andu-Bisheng and Liyue-Banyue basemental layer-blocks. The basic characteristics of the basemental layer-blocks have been dicussed, and three intra-plate basin groups are identified. The intra-plate basins within Nansha micro-plate can be divided into three basin groups of Nanwei- Andu, Feixin-Nanhua, and Liyue-North Palawan based on the different geodynamics. In the light of pluralistic geodynamic concept, the upheaving force induced by the mid-crust plastic layer is proposed as the main dynamical force which causes the formation of the intra-plate basins within the Nansha micro-plate. Finally, models of a face-to-face dip-slip detachment of basemental layerblock and a unilateral dip-slip-detachment of basemental layer-block are put forward for the forming mechanisms of the Nanwei Andu and Liyue-North Palawan intra-plate basin groups, respectively.

Size-dependent effect on biaxial and shear nonlinear buckling analysis of nonlocal isotropic and orthotropic micro-plate based on surface stress and modified couple stress theories using differential quadrature method

The size-dependent effect on the biaxial and shear nonlinear buckling analysis of an isotropic and orthotropic micro-plate based on the surface stress, the modified couple stress theory （MCST）, and the nonlocal elasticity theories using the differential quadrature method （DQM） is presented. Main advantages of the MCST over the classical theory （CT） are the inclusion of the asymmetric couple stress tensor and the consideration of only one material length scale parameter. Based on the nonlinear von Karman assumption, the governing equations of equilibrium for the micro-classical plate consid- ering midplane displacements are derived based on the minimum principle of potential energy. Using the DQM, the biaxial and shear critical buckling loads of the micro-plate for various boundary conditions are obtained. Accuracy of the obtained results is validated by comparing the solutions with those reported in the literature. A parametric study is conducted to show the effects of the aspect ratio, the side-to-thickness ratio, Eringen＇s nonlocal parameter, the material length scale parameter, Young＇s modulus of the surface layer, the surface residual stress, the polymer matrix coefficients, and various boundary conditions on the dimensionless uniaxial, biaxial, and shear critical buckling loads. The results indicate that the critical buckling loads are strongly sensitive to Eringen＇s nonlocal parameter, the material length scale parameter, and the surface residual stress effects, while the effect of Young＇s modulus of the surface layer on the critical buckling load is negligible. Also, considering the size dependent effect causes the increase in the stiffness of the orthotropic micro-plate. The results show that the critical biaxial buckling load increases with an increase in G12/E2 and vice versa for E1/E2. It is shown that the nonlinear biaxial buckling ratio decreases as the aspect ratio increases and vice versa for the buckling amplitude. Because of the most lightweight micro-composite materials with high strength/weight and stiffness/weight ratios, it is anticipated that the results of the present work are useful in experimental characterization of the mechanical properties of micro-composite plates in the aircraft industry and other engineering applications.

Geochemical characteristics and exploration significance of ultra-deep Sinian oil and gas from Well Tashen 5,Tarim Basin,NW China

The Well Tashen 5(TS5),drilled and completed at a vertical depth of 9017 m in the Tabei Uplift of the Tarim Basin,NW China,is the deepest well in Asia.It has been producing both oil and gas from the Sinian at a depth of 8780e8840 m,also the deepest in Asia in terms of oil discovery.In this paper,the geochemical characteristics of Sinian oil and gas from the well were investigated and compared with those of Cambrian oil and gas discovered in the same basin.The oil samples,with Pr/Ph ratio of 0.78 and a whole oil carbon isotopic value of31.6‰,have geochemical characteristics similar to those of Ordovician oils from the No.1 fault in the North Shuntuoguole area(also named Shunbei area)and the Middle Cambrian oil from wells Zhongshen 1(ZS1)and Zhongshen 5(ZS5)of Tazhong Uplift.The maturity of light hydrocarbons,diamondoids and aromatic fractions all suggest an approximate maturity of 1.5%e1.7%Ro for the samples.The(4-+3-)methyldiamantane concentration of the samples is 113.5 mg/g,indicating intense cracking with a cracking degree of about 80%,which is consistent with the high bottom hole temperature(179℃).The Sinian gas samples are dry with a dryness coefficient of 0.97.The gas is a mixture of kerogen-cracking gas and oil-cracking gas and has Ro values ranging between 1.5%and 1.7%,and methane carbon isotopic values of41.6‰.Based on the equivalent vitrinite reflectance(R_(eqv)=1.51%e1.61%)and the thermal evolution of source rocks from the Cambrian Yu'ertusi Formation of the same well,it is proposed that the Sinian oil and gas be mainly sourced from the Cambrian Yu'ertusi Formation during the Himalayan period but probably also be joined by hydrocarbon of higher maturity that migrated from other source rocks in deeper formations.The discovery of Sinian oil and gas from Well TS5 suggests that the ancient ultra-deep strata in the northern Tarim Basin have the potential for finding volatile oil or condensate reservoirs.

A Monolithic, FEM-Based Approach for the Coupled Squeeze Film Problem of an Oscillating Elastic Micro-Plate Using 3D 27-Node Elements

In this study we describe an FEM-based methodology to solve the coupled fluid-structure problem due to squeeze film effects present in vibratory MEMS devices, such as resonators, gyroscopes, and acoustic transducers. The aforementioned devices often consist of a plate-like structure that vibrates normal to a fixed substrate, and is generally not perfectly vacuum packed. This results in a thin film of air being sandwiched between the moving plate and the fixed substrate, which behaves like a squeeze film offering both stiffness and damping. Typically, such structures are actuated electro-statically, necessitating the thin air gap for improving the efficiency of actuation and the sensitivity of detection. To accurately model these devices the squeeze film effect must be incorporated. Extensive literature is present on mod- eling squeeze film effects for rigid motion for both perforated as well as non-perforated plates. Studies which model the plate elasticity often use approximate mode shapes as input to the 2D Reynolds Equation. Recent works which try to solve the coupled fluid elasticity problem, report iterative FEM-based solution strategies for the 2D Reynolds Equation coupled with the 3D elasticity Equation. In this work we present a FEM-based single step solution for the coupled problem at hand, using only one type of element (27 node 3D brick). The structure is modeled with 27 node brick elements of which the lowest layer of nodes is also treated as the fluid domain (2D) and the integrals over fluid domain are evaluated for these nodes only. We also apply an electrostatic loading to our model by considering an equivalent electro-static pressure load on the top surface of the structure. Thus we solve the coupled 2D-fluid-3D-structure problem in a single step, using only one element type. The FEM results show good agreement with both existing analytical solutions and published experimental data.

Occurrence of Mafic Rocks within Ediacaran Strata in the Aksu Region,NW Tarim Craton,and its Geological Implications

The Tarim Craton is an ancient Precambrian continental block,and detailed knowledge of its thermo-tectonic history is crucial for understanding the early history of continental evolution.Abundant layered mafic rocks,which have commonly been regarded as basalts,occur within the Ediacaran Sugetbrak Formation(Fm.)in the Aksu region of the northwestern Tarim Craton.Clear intrusive features have now been discovered,including mafic rocks truncating Ediacaran sedimentary layers,exhibiting an intrusion-baked margin where they interact with both the overlying and bottom wall rocks,and displaying a fine-grained transition zone from their interior to their margins.The new findings demonstrate that these mafic rocks within the Aksu Ediacaran strata were not erupted basalts but instead are intrusive diabase dykes.Therefore,these mafic rocks cannot be used to constrain the timing of the Sugetbrak Fm.in the Aksu area,nor as marker layers for regional stratigraphic correlation.Furthermore,the Ediacaran thermo-tectonic evolution in this region,deduced from the assumption that the mafic rocks are lavas,needs to be revised.

Nitrogen isotope stratigraphy of the Early Cambrian successions in the Tarim Basin:Spatial variability of nitrogen cycling and its implication for paleo-oceanic redox conditions

The Early Cambrian represents a critical time period characterized by extraordinary biological innovations and dynamic redox conditions in seawaters.Nitrogen isotopic signatures of ancient sediments have the potential to elucidate the evolutionary path of marine redox states and the biogeochemical nitrogen cycle within the water column of the Early Cambrian ocean.While existing research on this topic has predominantly focused on South China,the exploration of other continental margins has been limited,leaving contradictory hypotheses untested.In this study,pairedδ^(15)N andδ^(13)C org analyses were performed on the Lower Cambrian successions from the Shiairike section(inner ramp)and Well Tadong 2(deep shelf/basin)in the northwestern and eastern Tarim Basin,respectively.Our data from the Shiairike section reveal a discernible shift in the operation of different nitrogen cycles for the black chert-shale unit,also referred to as the black rock series in Chinese literature,of the Yurtus Formation(Fortunian stage to lower Stage 3).Oscillatingδ^(15)N values for its lower part are suggestive of alternating anaerobic assimilation of NH 4+and denitrification/anammox.This is likely attributed to a shallow,unstable chemocline consistent with the upwelling and incursion of deep,anoxic waters during a major transgression.In contrast,aerobic nitrogen cycling,indicated by positiveδ^(15)N values of>2‰,dominated the upper part alongside a reduction in upwelling intensity.On the other hand,theδ^(15)N signatures of Xishanbulake and Xidashan Formations of Well Tadong 2,which encompass a time interval from the Cambrian Fortunian Age to Age 4,are indicative of N_(2)fixation by diazotrophs as the major nitrogen source.The two studied intervals,although not time-equivalent,exhibit separated states of nitrogen cycling at least during the deposition of the Yurtus black rock series.The spatially different nitrogen cycling of the studied sections is compatible with a redox-stratified ocean during the deposition of the Yurtus black rock series.The build-up of a NO_(3)−reservoir and aerobic nitrogen cycling in seawater was largely restricted to near-shore settings whereas anaerobic nitrogen cycling dominated by N_(2)fixation served as the main nitrogen uptake pathway in off-shore settings.

Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure coupling.Triaxial stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility analysis.According to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more ductile.This reduces the amount of time it takes for the rock to transition from brittle to plastic.When temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal pressurization.The sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are compared.This provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

New findings of Changxingaspis(Xiushuiaspidae,Galeaspida)from the Silurian of Tarim Basin and Zhejiang Province,China

New discovery of the early Silurian fossil fish Changxingaspis(Xiushuiaspidae,Galeaspida),Changxingaspis nianzhongi sp.nov.and C.gui,are described from the Tataertag Formation in Tarim Basin and the Kangshan Formation in Zhejiang Province,respectively.C.nianzhongi mainly differs from C.gui in the shape of the median dorsal opening that is transverse elliptic with a width/length ratio of about 3.0,the long lateral transverse canals extending to the lateral margin of the headshield,and the second lateral transverse canal with dichotomous branchings.Discovery of C.nianzhongi from the Tataertag Formation and C.gui from the Kangshan Formation provide direct evidence on the specific level for the correlation between these two formations,which further supports the Silurian fish-bearing red beds in northwest Zhejiang belonging to the Silurian Lower Red Beds(LRBs)rather than the Upper Red Beds(URBs).Additionally,as the first record of the Changxingaspis in Tarim Basin,it extends the paleogeographical distribution of this genus from the South China Block to the Tarim Block,providing new evidence to support faunal exchanges between these two blocks and the hypothesis of a united Tarim-South China Block during the early Silurian.

The Lower Cambrian Xiaoerbulake Formation in the Tarim Basin as a potential carbonate source rock

The oil and gas exploration of the Middle and Lower Cambrian in the Tarim Basin reveals widely distributed source rocks with the Yuertusi Formation being recognized as high-quality source rocks that are distributed in a rather small range.The Xiaoerbulake Formation that is right under the Yuertusi Formation has also been eyed as potential high-quality source rocks and is studied through analyses focusing on the stratigraphic development,the abundance,type,and maturity of organic matter,and the paleoproductivity of a dark-colored algae dolomite within the formation.The results show that the dolomite is rich in organic matter of mainly types Ⅰ and Ⅱ kerogens.Although reached the high mature to over-mature stage,the dolomite was deposited in an anoxic sedimentary environment featuring a high paleoproductivity level and a high organic carbon burial efficiency,quite favorable for the development of high-quality source rocks.The study provides material evidence to the Middle-Lower Cambrian subsalt source rock-reservoir-caprock combination model for the Tarim Basin.

Geometry and formation mechanism of tension gashes and their implication on the hydrocarbon accumulation in the deep-seated strata of sedimentary basin:A case from Shunnan area of Tarim Basin

With the theoretical and technological developments related to cratonic strike-slip faults,the Shuntuoguole Low Uplift in the Tarim Basin has attracted considerable attention recently.Affected by multi-stage tectonic movements,the strike-slip faults have controlled the distribution of hydrocarbon resources owing to the special fault characteristics and fault-related structures.In contrast,the kinematics and formation mechanism of strike-slip faults in buried sedimentary basins are difficult to investigate,limiting the discussion of these faults and hydrocarbon accumulation.In this study,we identified the characteristics of massive sigmoidal tension gashes(STGs)that formed in the Shunnan area of the Tarim Basin.High-resolution three-dimensional seismic data and attribute analyses were used to investigate their geometric and kinematic characteristics.Then,the stress state of each point of the STGs was calculated using seismic curvature attributes.Finally,the formation mechanism of the STGs and their roles in controlling hydrocarbon migration and accumulation were discussed.The results suggest that:(1)the STGs developed in the Shunnan area have a wide distribution,with a tensile fault arranged in an enéchelon pattern,showing an S-shaped bending.These STGs formed in multiple stages,and differential rotation occurred along the direction of strike-slip stress during formation.(2)Near the principal displacement zone of the strike-slip faults,the stress value of the STGs was higher,gradually decreasing at both ends.The shallow layer deformation was greater than the deep layer deformation.(3)STGs are critical for connecting source rocks,migrating oil and gas,sealing horizontally,and developing efficient reservoirs.This study not only provides seismic evidence for the formation and evolution of super large STGs,but also provides certain guidance for oil and gas exploration in this area.

Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum geology.Since it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the DLOA.Hence,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the depth.In this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained collectively.The depth corresponding to a dry layer ratio of 100%is the DLOA.Based on this,a quantitative prediction model for the DLOA was finally built.The results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep layer.The critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the reservoir.The depth of the DLOA was 9,000 m.This study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

The Middle and Lower Cambrian salt tectonics in the central Tarim Basin,China:A case study based on strike-slip fault characterization

Due to the considerable depth of the salt layers and the lack of calibration by exploratory drilling,the interpretation of the Middle and Lower Cambrian salt formations in the central Tarim Basin poses a challenge.In this paper,we apply the coupling and decoupling deformation theory in salt tectonics to analyze the No.7 fault mapped in the seismic datasets by the response characteristics of the Middle and Lower Cambrian layers.By quantifying the stratigraphic framework of the Middle and Lower Cambrian strata,we define the position of the salt layer with the seismic data.Structural decoupling is observed in the Middle and Lower Cambrian sequences in the Shuntuoguole Low Uplift,while deformation coupling is observed in these two sequences in the Shaya Uplift.

Effect of CO_(2)flooding in an oil reservoir with strong bottom-water drive in the Tahe Oilfield,Tarim Basin,Northwest China

The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir with strong bottom-water drive in Tarim Basin,Northwest China.Such parameters were analyzed as solubility ratio of CO_(2)in oil,gas and water,interfacial tension,in-situ oil viscosity distribution,remaining oil saturation distribution,and oil compositions.The results show that CO_(2)flooding could control water coning and increase oil production.In the early stage of the injection process,CO_(2)expanded vertically due to gravity differentiation,and extended laterally under the action of strong bottom water in the intermediate and late stages.The CO_(2)got enriched and extended at the oil-water interface,forming a high interfacial tension zone,which inhibited the coning of bottom water to some extent.A miscible region with low interfacial tension formed at the gas injection front,which reduced the in-situ oil viscosity by about 50%.The numerical simulation results show that enhanced oil recovery(EOR)is estimated at 5.72%and the oil exchange ratio of CO_(2)is 0.17 t/t.

Petroleum Accumulation Associated with Volcanic Activity in the Tarim Basin —— Taking Tazhong-47 Oilfield as an Example

The discovery of the Tazhong-47 oilfield confirmed that it is realistic to explore oil and gas fields around igneous rocks in the Tarim basin. The favorable conditions for petroleum accumulation due to volcanic activity and igneous rocks formed during the activity show in two aspects. A) The contact surface of igneous rocks and the surrounding sedimentary rocks, like a vertical unconformity surface, formed the conduit of petroleum migration. Petroleum would accumulate once it encountered a trap in which the reservoir had fine porosity and permeability. B) It formed a trap barriered by igneous rocks, or changed or cut the original trap. In addition, volcanic rocks are a kind of potential reservoir, there are many such examples in the world, and oil also shows in the Permian igneous rocks in well Zhong-1 on Tazhong uplift. Petroleum accumulation associated with volcanic activity will be a new exploring field in the Tarim basin.

Application of Prediction Techniques in Carbonate Karst Reservoir in Tarim Basin

Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper.

Effects of climate change on water resources in Tarim River Basin, Northwest China

Based on hydrology, temperature, and precipitation data from the past 50 years, the effects of climate change on water resources in Tarim River Basin in Northwest China were investigated. The long-term trends of the hydrological time series were detected using both parametric and nonparametric techniques. The results showed that the increasing tendency of the temperature has a 5% level of significance, and the temperature increased by nearly 1℃ over the past 50 years. The precipitation showed a significant increase in the 1980s and 1990s, and the average annual precipitation exhibited an increasing trend with a magnitude of 6.8 mm per decade. A step change occurred in both the temperature and precipitation time series around 1986. The streamflow from the headwater of the Tarim River exhibited a significant increase during the last 20 years. The increase in temperature, precipitation, and streamflow may be attributed to global climate change.

Diagenesis and Its Effect on Reservoir Quality of Silurian Sandstones,Tabei Area,Tarim Basin,China

The diagenetic processes of the Tabei sandstones in the Tarim Basin include compaction, cementation （quartz overgrowths, calcite, clay minerals and a minor amount of pyrite）, and dissolution of the feldspar and calcite cement. Porosity was reduced by compaction from an assumed original 40% to about 22.1%. Cementation reduced porosity to 26.6%. The Tabei sandstones lost a little more porosity by compaction than by cementation. Quartz cementation, especially syntaxial quartz overgrowth, is a major cause of porosity-loss in many reservoirs in moderately to deeply buried sandstone. Calcite cementation played a key role in the porosity evolution of sandstones. At the early stage of burial, the early calcite cement occupied most of the pore spaces resulting in significant porosity. On the other hand, some primary porosity has been preserved due to incomplete filling or the presence of scattered patches of calcite cement. In addition to calcite, several clay minerals, including illite and chlorite occurred as pore-filling and pore-lining cements. The pore-lining chlorite may have helped in retaining the porosity by preventing the precipitation of syntaxial quartz overgrowths. Illite, which largely occurred as hair-like rims around the grains and bridges on the pore throats, caused a substantial deterioration of penetrability of the reservoir. Calcite cement dissolution was extensive and contributed significantly to the development of secondary porosity.

Degradation of Populus euphratica community in the lower reaches of the Tarim River, Xinjiang, China

To investigate the relationships between the degradation of plant community and groundwater level in the lower reaches of the Tarim River, nine monitored sections were set along the main stream, where there had been no runoff for nearly 30 years. The characteristics of plant communities were analyzed. It was found that the coverage of trees gradually decreased along the groundwater depth gradient, while the coverage of shrubs slightly increased rather than decreased at first and then gradually decreased, and the coverage of herbs steadily decreased at the beginning and then quickly decreased. The species diversity and species richness of both herbs and woody plants showed obvious degrading trends, while the variations in species evenness were slight. The degrading sequences of species were related to their physiological and ecological characteristics, especially their sensitivity to changes of groundwater table. The herbs with shallow roots first degenerated or disappeared when the groundwater table fell, and then did the deep-rooted herbs, and finally the trees and shrubs with strong tolerance to drought degenerated. The Populus euphratica communities showed typical degrading characteristics, namely the dominant species Populus euphratica remained its dominant status during the degradation. Overall, the existence of strongly tolerant-drought species was the obvious indication of plant species degradation; while simplification of community structure and the decrease of species richness were the obvious indication of plant community degradation.

Streamflow trends and hydrological response to climatic change in Tarim headwater basin

This paper has studied the change of streamflow and the impact of climatic variability conditions on regional hydrological cycle in the headwater of the Tarim River Basin. This study investigates possible causes of observed trends in streamflow in an environment which is highly variable in terms of atmospheric conditions, and where snow and ice melt play an important role in the natural hydrological regime. The discharge trends of three head streams have a significant increase trend from 1957 to 2002 with the Mann-Kendall test. Complex time-frequency distributions in the streamflow regime are demonstrated especially by Morlet wavelet analysis over 40 years. The purpose is to ascertain the nature of climatic factors spatial and temporal distribution, involved the use of EOF （Empirical Orthogonal Function） to compare the dominant temperature, precipitation and evaporation patterns from normally climatic records over the Tarim＇s headwater basin. It shows that the first principal component was dominated since the 1990s for temperature and precipitation, which identifies the significant ascending trend of spatial and temporal pattern characteristics under the condition of the global warming. An exponential correlation is highlighted between surface air temperature and mean river discharge monthly, so the regional runoff increases by 10%-16% when surface air temperature rises by 1 ℃. Results suggest that headwater basins are the most vulnerable environments from the point of view of climate change, because their watershed properties promote runoff feeding by glacier and snow melt water and their fundamental vulnerability to temperature changes affects rainfall, snowfall, and glacier and ice melt.