The first discovery of gas hydrate reservoir in middle-latitudes zone was made in the Qilian Mountain permafrost zone. To evaluate the geochemical exploration method for gas hydrate in middle-latitudes zone, Muli area was chosen as the test area. Soil headspace gas, acid extracted hydrocarbon, carbon isotope of methane and carbonate were tested. The results reveal that geochemical anomalies were consistent with the gas hydrate reservoir underneath. The carbon isotope of methane and hydrocarbon composition analysis of the surface geochemical anomaly zone indicated a thermo-pyrogenation origin, suggesting the gas source of the potential gas hydrate reservoir in this area may contribute by oil gas and coal-formed gas. The origin model was also studied for the gas hydrate reservoir. An integrated exploration project which targets at gas hydrate, oil and coal bed methane altogether was recommended as the next step in Muli area.

Two types of oil reservoirs, related to Cenozoic igneous rocks, exist in Qikou depression,i.e., basic volcanic rock reservoir and diabase alteration zone reservoir, both of them are tectonic-lithological oil reservoirs. Horizontally, they are affected by distribution of igneous rocks and hydrocarbon source rocks, and are mainly focused on the transformation belt related to NE and EW fractures. Vertically, they are controlled by regional cap rocks, and are almost kept in Es^z_１ and Ed. In these two strata within the transformation belt, whether hydrocarbon can accumulate into igneous rocks or not mainly depend on the type of reservoir system. As for open storage system, on one hand reservoir spaces can be protected by fluid replacement to discharge mineralized water and reduce the formation of secondary minerals, on the other hand the reservoir spaces can be increased and expanded to further improve reservoir conditions by the way that: organic acid fluids get into the spaces and dissolve amygdale, fracture fillings and unstable minerals in igneous rock. In addition, open storage system provides the necessary conducting channel for hydrocarbon，through which hydrocarbon can seep from source rocks to accumulate into igneous rock to form oil reservoirs. In closed reservoir system, there are no these conditions mentioned above, the reservoir property has been lost partly because mineralized water can not be expelled out of igneous rocks and result in the formation of secondary minerals to fill reservoir space. Moreover, part of the unfilled spaces have no intercommunication channel between igneous reservoir and hydrocarbon source rock and become dead spaces, which makes it difficult to accumulate oil and gas in the closed reservoir system.

Through the analysis of sandstone clastic composition, debris types, heavy mineral assemblages, REE and trace elements of Xujiahe Formation in Sichuan foreland basin secondary structure unit, the authors studied the provenance and tectonic setting of Xujiahe Formation sediments in Sichuan foreland basin. The results indicate that most of the clastic materials were derived from the orogenic recycle belt, some of them maybe come from the mixed area before the orogenesis, different tectonic units and strata exist different provenance：the provenance of west Sichuan depression is controlled by Longmen mountain thrust nappe belt, the provenance of northeast Sichuan depression is controlled by Micang-Daba mountain thrust nappe belt, the provenance of southeast Sichuan depression is controlled by Xuefeng old land, while the provenance of medieval Sichuan uplift is controlled by the southern Emei archicontinent. Tectonic evolution characteristics of source area appear from a continental margin transform to the continental island arc, and Longmenshan thrust nappe activity in Xujiahe fourth phase is more stronger than Xujiahe second phase.

Many detailed field surveys and comprehensive researches have been made to find sandstone copper deposit in Jiwa area, Tibet. Oligocene Rigongla formation sandstoneswere the ore-bearing horizon. The deposit type is strata-bound deposit. Series of provenance analysis technique, for instance, quantitative detrital minerals analysis, elementary geochemical methods and heavy minerals combination analysis,are used to explorethe provenance features and tectonicbackground of Rigongla sandstones. The main lithology is lithic sandstone with a poor sorting and psephicity and low maturation of texture. The detrital compositions hintthe main setting background of provenance is continental island arc, the geochemical characteristics are high value of siliceous, enrich in LREE, relatively depleted in HREE, and negative Eu anomalies. They all show that the provenance is closely related to acid volcanic rocks, the main setting background of Rigongla formation sandstone is continental island arc, the lithic sandstones came from felsic part of upper crust, heavy mineral combinations mainlyarehematite-limonite and magnetite,zircon,tourmaline, garnet,which were related to intermediate-acid magmatic rocks. Sandstone was deposited in dry, restricted shallow water and oxidizing environment. The morphological characteristics of zircons indicate that provenance is close to mother rocks. The correlation analysis of heavy minerals also shows that provenance is closely related to volcanic rocks. Comparingto acid volcanic rocks of the lower stratum and early cretaceous volcanic rocks in this area, trace elements and heavy mineral sreveal that the characteristics of detrital material source area were showed genetic relationship from petrology characteristics, geochemical characteristics and heavy mineral assemblages. The provenance of fragments were closely related to volcanic activities, may come from the acid volcanic rocks of early Cretaceous associated with the southward subduction of the Bangong Co-Nujiang oceanic crust and northward subduction of the Yalung Zangbo oceanic crust. Sandstone copper deposits was found in Rigongla Formation, volcanic rock provides the source of ore-forming materials.

Three sets of the Early Paleozoic deep-water black shales, respectively named of  ∈₁h and ∈₁ht, O₃w, S₁g and S₁x,  are mainly developed in Anhui Province, the Lower Yangtze subcontinent.  Total of 27 samples sampled from the three sets of black shale series for ICP-MS measurement were used to analyze their geological settings of tectonic and sources. Results show that within these shale samples, elements Li, Be, Rb, Ba, Cs, W, Th, U, Cd, Bi, Pb are enriched, Sc、Sr，Cr、Cu、Ga、Co、Ni are poor, contents of rare earth elements are high, Eu is obviously  negative, and the fractionation between light and heavy REE is being pronounced. Trace inactive element content and the ratio of characteristics of the tectonic setting discrimination diagrams indicate that the black shales could have been deposited in a deep-water and lag sedimentary environment within the continental island arc and active continental margin in early stage, fllowing a passive continental margin in late stage. The parent rocks could be mainly derived from the recycled sediments of the upper crust and the Post-Archean strata as well as  the undifferentiated Archaean crust and  basalts. According to the  devolpment of the ancient Jiangnan island and the geochemistry comparison of the Lower Paleozoic black shales from other place of the Yangtze continent, it is proposed that the black shales in Anhui Province could have been southwardly sourced from the ancient Jiangnan island.

In order to find out the response of diagenesis to hydrocarbon fluid flowin the Third Member of Shahejie Formation in central uplift belt of Dongying depression,the relationshipbetween the formation of authigenic minerals and hydrocarbon fluids flow were analyzed based on the results of microscopic observation, inclusion thermometry, scanning electron microscope and cathode luminescence.the diagenetic sequence is: the first period of quartz overgrowth→the first period of carbonate cements（pyrite particles）→a layer of chlorite film→the second period of carbonate cements→the second period of quartz overgrowth（the first period of kaolinite）→the third period of carbonate cements→ the third period of quartz overgrowth（the second period of kaolinite）→the fourth period of ferric carbonate cements（pyrite particles）. The first hydrocarbon filling occurred duringthe later stage of the second period of carbonate cements formation. The second and third hydrocarbon filling occurred duringthe mid-to-late stage of the third period of carbonate cements formation. The formation of the fourth period of carbonate cements representsthe end of large-scale hydrocarbon filling. Hydrocarbon fluid has great impact on the formation of three types of authigenic minerals in the study area, including authigenic kaolinite, ferric carbonate minerals and pyrite. In the sandstone reservoir, the activity of hydrocarbon fluid can be identified by various diagenetic phenomena, such as embayed corrosion of the second and the third period of carbonate cements, large growth of kaolinite, and paragenetic association of the fourth period of carbonate cements and the pyrite. In the sandstone strata with high oil saturation, hydrocarbon fluid may lead to large-scale corrosion of carbonate cements and the corrosion of feldspar, which causeagreat formationof kaolinite. In addition, paragenetic association of ferric carbonate cements and pyrite can be observed at the interface of sandstone and mudstone. However, in the strata with low oil saturation or oil-free, due to lacking of organic acid provided by hydrocarbon fluid, kaolinite is less developed, and the early period of carbonate cements is well preserved.

Kuqafold thrust belt (KFTB) is a Cenozoic rebuilt foreland basin formed by the collision between Indian and Eurasian plate. Kumugeliem Group (K. G.) and Jidike Formation (J. F.) salt was sedimented during Paleogene and Neogenere spectively and salt diapir was developed in the west of KFTB.Field survey, seismic profile interpretation and balanced section were analysed for the mechanism research of salt diapir. Two types of salt diapirs were recognized in the west of KFTB. One is the salt stock developing along Kalayuergun strike-slip fault and the other is the salt wall located in the Tuzimaza area. The growth stratigraphy of the west KFTB was mainly developed in the middle of Kuqa Formation and its upper layers. The unconformity was developed in the middle of Kuqa Formation, showing the development of the salt wall. The salt stock is controlled by the strike-slip;and the tensional stress component of strike-slip caused the salt extruding to the surface. The salt wall is controlled by the sediment differential loading. The huge different sediment thickness made the salt star to develop. The salt wall continued to develop in the later period and the infected by the thrust fault.

The Galashan extensional detachment structure is located in the east slope of northern Great Xing’an Ranges. There develop SE-dipping foliation, interlayer fold, augen structure, low-angle normal fault, sheath fold and rodding structures, as well as various ductile deformation micro-textures, such as mica fish, rotated porphyroblast and quartz ribbon in the extensional detachment belt. The temperature of the ductile deformation is about 300-400 ℃. The asymmetric interlayer folds and lineations indicate a large-scale top to SE extensional detachment structure. The ⁴⁰Ar/³⁹Ar dating of the muscovite from the granitic gneiss and marble within the deformation zone gives 144-147 Ma age, which represents the ductile deformation age of the extensional detachment. Combined with the regional metamorphic core complex data, we suggest that the formation of Galashan extensional detachment structure should be related to the post-orogenic collapse of the thickened crust due to Mongo-Okhotsk orogeny, which resulted in the regional extension in the Great Xing’an Ranges area.

The Weibao Pb-Zn deposit is located in the western Qimantage, east Kunlun, Xinjiang Province. The stratiform ore bodies are controlled by the strata, and occur in the banded epidote diopsite skarn in middile-lower Langyashan Formation of Jixianian Period. Major Pb-Zn (Cu) ore belongs to epidote diopsite skarn type. The ore minerals consist of galena, sphalerite and chalcopyrite, and the gangue minerals are composed of diopsite, epidote, calsite, chlorite and garnet. The sphalerite is characterized by higher content of Fe (2.206%-2.679%), lower content of Ga, Ge, Cd and Zn/Cd (143-150), and the content of Ag in galena is lower (0.163%-0.210%), which indicates that the metallic minerals may be formed closely with magmatic fluid. There are two types of fluid inclusions, liquid-rich two-phase and gas-rich two-phase. The average homogenization temperatures of two types of inclusions are 268.2 and 273.1 ℃, respectively. The gas components of CO₂, CH₄, N₂ and H₂ in inclusions indicate the ore-forming fluid may be derived from magmatic fluid. In all, the initial oreforming fluid belongs to immiscibility, characterized by middle-high temperature, high salinity and low density. The values of δ³⁴S vary from 0.49‰ to 2.41‰, which indicates that sulfur in sulfides was mainly from the magma. The sulfides have ²⁰⁶Pb/²⁰⁴Pb values from 18.254 to 18.336,²⁰⁷Pb/²⁰⁴Pb values from 15.556 to 15.664,²⁰⁸Pb/²⁰⁴Pb values from 38.060 to 38.367, which suggests that ore-forming metals come from deep magmatic activity, with little crust mixing. In summary, the Weibao Pb-Zn deposit may be a layered skarn type deposit related to Indosinian magmatic activity.

Xincheng gold deposit of Shandong Province is a typical altered rock type gold deposit in the Jiaojia-Xincheng gold ore belt. The ore body is mainly located in the footwall of the Jiaojia-Xincheng fault zone within the pyrite phylic and the cataclasite of pyrite phylic near the fracture surface and it is significantly controlled by the fractured zone. The main ore minerals are pyrite, chalcopyrite, galena, sphalerite, native gold, electrum and argentit, etc. The main types of wall-rock alteration zone contain pyrite phyllic, phyllic, sericite, silicification, potassium and carbonate, etc., and the gold mineralization has a close relationship with pyrite phyllic and silicification alteration. The petrographic, microthermometric, laser Raman microspectroscopic in the single fluid inclusion were studied here, results showed that the hydrogen and oxygen isotope analysis on fluid inclusions were developed in auriferous ore of Xincheng gold deposit in the deep position. Also, it indicated that the numbers of the pure CO₂ fluid inclusions are conspicuously increased in the deep position of the deposit, with the existence of the CO₂-bearing fluid inclusions and the aqueous two-phrase fluid inclusions at the same time. The ore-forming fluids show the characteristics of low salinity (2.06%-10.24%), low density (0.54-0.97 g/cm³). Mineralization temperature is concentrated in 260-300 ℃, and the pressure ranges from 65 to 113 MPa, which equals to a depth of 6.51-8.82 km. And fluid immiscibility occurred in CO₂-NaCl-H₂O system in the ore-forming process. The hydrogen and oxygen isotope analysis indicated that the δD_SMOW of the ore-forming fluids is -75.1 ‰--61.4‰ and the δ¹⁸O_H2O is 4.80‰-6.40‰. Compare the characteristics and source of fluid to the typical “Jiaojia style” gold deposit, it showed that the ore-forming fluids of the Xincheng deposit are mainly from deep mantle fluids. Comprehensive study shows that the genesis of the deposit is the type of mantle-derived fluid mineralization in mesothermal type gold deposits.

The Mayang copper deposit located in the Central of Yuanma basin and near to Mount Xuefeng in the southern is a rarely sandstone type native copper deposit. The production of this deposit has a long history，and can be dated to Period of Spring and Autumn ，so far it has provided more than 2 million tons copper which about 90% from native copper. The ore bodies are multistory and mainly occur in the gray white or gray green sandstones of Jinjiang Formation of Cretaceous, and a single ore-body is stratified or lentoid. The native copper is important as cement in sandstones. In this paper, the content of major elements, trace elements and rare earth elements of the redbed rock, ores, native copper and chalcocite were calculated using the correlation analysis to discuss the relationship between the element character and copper mineralization. Kinds of elements, such as Fe, Ag, As, Ba, Sr, are positive correlated with Cu, which show these elements are closely related to the native copper formation. The native copper mineralization is due to the underground thermal water, and this type fluid may be low temperature and weak reduction environment.

The Asiha gold deposit is located in the eastern Kunlun uplift belt, and intrudes Jinshuikou Group in Proterozoic. The quartz diorite has closely spatio and temporal relationship with the gold mineralization in this area. The authors adopted LA-ICP-MS zircon dating, XRF and ICP-MS analysis for geochemical characteristics of the quartz diorite. The reasearch results indicate that the quartz diorite belongs to the calc-alkaline and metaluminous I type granite. The emplacement age of the intrusion is (238.4±1.4) Ma. REE patterns of different samples are basically in accordant, showing their comagmatic evolution. The quartz diorite is comparatively rich in LREE, with weak negative Eu anomalies, remarkably enriched in LILEs, depleted in HFSEs, with negative anomaly about TNT, which are similar to those of ligneous rock in Andean type continental margins. The fact that the values of Rb/Sr and Nb/Ta are between those of the crust and mantle, combined with widespread mafic microgranular enclaves, shows that the magma was derived from crust-mantle mixing source. In summary, the quartz diorite has the characteristics of I-type granite, formed in Indosinian, with crust-mantle mixing characteristics.

The Baiquesi and Daan granitic plutons on the northwestern margin of the Yangtze block have been investigated by zircon U-Pb dating and Hf isotope analysis. Research results indicate that U-Pb ages of zircons in the Baiquesi pluton can be divided into two groups: (855±6) Ma (n=23) and (917±14) Ma (n=3).The ε_Hf(t) values of the former are 3.8-10.4, and the one-stage Hf isotope model age varies from 1.00 to 1.27 Ga; The ε_Hf(t) values of the latter are 2.0-8.1, and the one-stage Hf isotope model are 1.14-1.40 Ga. However, the ages of the Daan pluton can be divided into six groups: (854±10) Ma (n=3), (801±7) Ma (n=3), (702±10) Ma (n=3), (565±6) Ma (n=1), (246±7) Ma (n=1) and (207±2) Ma (n=1). The ε_Hf(t) values of the Daan pluton are -12.6-11.4 (t=854 Ma), and the one-stage Hf isotope model ages and the two-stage Hf isotope model ages are 0.95-1.90 Ga and 1.02-2.55 Ga. The Baiquesi and Daan plutons were emplaced at (855±6) Ma and (854±10) Ma, respectively, which reflect a significant magmatic event in Bikou terrane, northwestern margin of Yangtze block, and the former was mainly derived from the Mesoproterozoic juvenile crustal source, while the latter was products of two end-member mixing magmas respectively sourced from the Mesoproterozoic juvenile crustal and the Neoarchean old crustal. In addition, the (917±14) Ma which is larger than the intruding age of the Baiquesi pluton represents the record of the Early Neoproterozoic magmatism. Ages which are smaller than the intruding age of Daan pluton probably record the subsequent modifications of other thermal events.

The granitoid rocks in Taili area, western Liaoning Province, are mainly composed of granitic gneiss, porphyritic granitic gneiss and biotite adamellite, and were once regarded as the Neoarchean granite. According to the occurrence sequence of various types of granitic rocks, the authors consider that the massive/gneissic biotite adamellite, located in south and north sides of the study region, intruded into granitic gneiss and porphyritic granitic gneiss as the apophysis or dike. Geochemical characteristics indicate that the biotite adamellite belongs to metaluminous-weakly peraluminous I-type granite, and shows volcanic arc granite characteristics. Zircons in the biotite adamellite are of complex origin. A large number of inherited zircons coexist with neonatal zircons. Neonatal zircons with obvious characteristics of magmatic crystallization are characterized by oscillating growth zonation and high Th/U values (0.15-1.70). Weighted average ages of two samples by LA-ICP-MS zircon U-Pb are (153.7±2.0) Ma and (153.7±4.7) Ma, respectively. The results show that the biotite adamellite belongs to the Late Jurassic granitoid plutons with source rock as meso-basic volcanic rocks of the lower crust. The origin of the biotite adamellite is tectonically linked to the subduction of the paleo-Pacific plate to the Asian continent.

The authors had systematically summarize and analyze the previous research results of isotopic geochemistry in Emeishan large igneous province (ELIP). According to the isotopic geochemical data of basalt and intrusions in ELIP, combined with its biostratigraphy, we propose a rough period of 251-263 Ma as the formation age of each rock unit in ELIP. Mafic-ultramafic instrusions in ELIP formed in ~259 Ma, and the basalts, which was viewed as the bulk of ELIP formed in 251-253 Ma. The isotopic geochemical data of Sr-Nd, Re-Os, Lu-Hf and O indicate that the ELIP originate from either mantle plume or subcontinental lithosphere mantle (SCLM). The Emeishan basalts show similar Sr-Nd isotopic characteristcs to the mafic intrutions which is rich of Fe-Ti oxide; and the maficultramafic instrusions bearing Cu-Ni sulfides are closer to crust material, which might be related to crust contamination.

In order to study the frost resistance and durability of concrete structures under double factors of salts attack and freezing-thawing cycles in seasonal frozen soil area, multi-salt solution with three kinds of mass fraction and water were prepared according to the type and quantity of the main dissolved salts in the spring soil of Daan region. Specimens of ordinary concrete with different mixture ratios, two kinds of air-entraining concrete and two kinds of fly-ash concrete were prepared for the multiple salts and freezing-thawing cycle tests. The mass loss, dynamic elastic modulus reduction and microstructure of tested samples were analyzed. Results showed that concrete erosion was aggravated by multi-salt under the action of freezing-thawing cycles. The degree of frozen damage was related to the mass fraction of salt solution, times of freezing-thawing cycle, air content in concrete and fly-ash addition ratio. Reasons that lead salt-frozen damage occur were expansion pressure produced during the course of water turning into ice, the seepage pressure of ice and water and the chemical erosion and crystalline swelling of salt from the reaction between multi-salt and cement hydration production, among which salt crystallization played more important role in the damage of concrete internal structure.

The deformation modulus of fault rock mass is an important parameter to denote its mechanical characteristic, and it is obviously related to the environment. A large scale hydropower project was taken as an example to analyze the influence of deformation modulus of fault rock masses on dam base stability based on site test and theory and 3D-numerical analysis. Result indicates that if the deformation modulus of fault rock mass increases from 0.6 Gpa to 4.0 GPa, the horizontal displacement at key point in the dam will decrease 0.544-0.846 mm, the vertical displacement at key point in the dam will decrease 1.190-2.232 mm and the maximal tensile stress at key point in the dam will decrease 0.06 MPa because of the increase in the deformation modulus of fault rock mass after impoundment of hydropower station and without influence of water infiltration, which is advantageous to stability of dam base.

The runoff yield and slope failures are the source of debris flows in watersheds. The previous study focuses on the deterministic mechanism formation of slope failures for debris flow initiation and hydrological processes for debris flow runoff calculation. This paper aims to reveal and discuss the randomness process of slope failures. Artificial rainfall experiment was conducted on selected typical debris flow source region to observe the movement features of slope runoff and soil body. Results showed that slope failure and runoff formation are two separated processes. Runoff generation was continuous, evenly and stably distributed on slope. Slope failure presented a sequence of soil body collapse with the features of intermittence in time, aggregation in space, and remarkable fluctuation in magnitude. Slope failures time interval fit the Poisson distribution and its magnitude fit the powerlaw. The soil and water supplies were unsynchronized, the debris flow initiation depend not only on the flood generation, but also on the spatiotemporal characteristics of the slope failure processes, which leads to high variety and fluctuation of debris flows even under the same rainfall condition. This study contributes the debris flow formation and runoff calculation by taking debris flow formation as a randomness and discontinuous process and revealing the spatial characteristics of slope failures.

Lizheng software for deep foundation pit was used to analyze one side of a real project. By changing the value of pre-stress, number of anchor line and adjusting the parameter of soil pressure, the change of displacement, lengthen of anchored part and steel consumption were calculated and analyzed to study the effects of anchor-pile in foundation pit support and its influences on the surroundings. Study results showed that for one line anchor-pile, when the pre-stress increases to a certain value, pre-stress increasing was no longer useful to decrease foundation displacement, but steel consumption would be increased obviously. Two lines of anchors without pre-stress had an obvious effect on foundation deformation control, and it led to less steel consumption and slight surroundings influence. Only by selecting a proper adjustment parameter of soil pressure, letting the foundation pit to form proper displacement, the active soil pressure adopted in calculation can be closed to the practical one and the design of foundation pit support can be stable and reliable.

Brazing method was introduced into designing and manufacturing diamond drill bit with high matrix to improve its drilling efficiency and extend its life. Firstly, impregnated diamond blocks with good wear resistance were manufactured by hot pressing method. Then new steel body of drill bit including multilayer nozzles and water way was designed, and the welding grooves were formed between two nozzles. Lastly, the impregnated diamond blocks were welded in the drill bit steel body. The life of diamond drill bit manufactured by welding method was improved obviously. Field experimental results showed that the drilling efficiency of two Φ75/54.5 mm high matrix diamond bits was increased by 41.7% and 8.3% respectively, their lives were improved by 50.4% and 32.9% respectively compared with the conventional one. The two times braze welding method takes the advantage of hot pressing method, solves the breaking and blocking off problem of drilling bit, and improves its life greatly.

Based on the spatial and temporal distribution theory of basin, the evolution of the Nenjiang River basin runoff space-time laws was analyzed. And it focused on the attribution analysis of the factors of topography effect. Based on the precipitation data from 1955 to 2003(49 a) and runoff data from 1955 to 1973(19 a), the evolution of runoff, surface runoff and underground runoff were analyzed from upstream to downstream of the representa-tive hydrological stations. What the results shows is as follows: 1)In Nenjiang River basin，the inter-annual and space-time change of rainfall are consistent. So the impact of spatial and temporal distribution of precipitation can be ignored when runoff evolution is analyzed.2)The headwater differences from upstream to downstream can be determined through annual runoff evolution.The upstream is surface runoff. In the spring, the runoff is from snowmelt.  In the rainy season, it is from atmospheric precipitation. In the dry season, it comes from groundwater recharge. The downstream is mainly underground runoff.3)Because of slope and hydrogeological conditions, it is easier for upstream to produce flow. From upstream to downstream, the runoff volume is gradually reduced.

Reading and writing precipitation and well data are all based on each grid in the existing MODFLOW. So building regional groundwater flow numerical models with refined spatial and temporal discretization often involves storing and reading large quantities of well and precipitation data. However, the storage requirement can be prohibitive and the program efficiency can be quite low. To address this problem, we have modified the existing package RCH and also developed a new package named RAW (recharge and well), which is based on the existing packages in MODFLOW. The improved MODFLOW program can only read values of every subarea and the subarea number of each grid which is stored in the RCH or RAW file, and then allocates the values to corresponding grids. With the RAW package, the area recharge and discharge could occur in all layers. Therefore, it could be used to simulate the source and sink term, like groundwater exploitation and agricultural irrigation return. The correctness has been verified and the efficiency has been tested through simulating a theoretical groundwater flow model and a real North China Plain model respectively. Compared with the traditional method of storing data, the size of RCH and RAW file decreases 1/145 and 1/255 respectively, and the time ratio for reading data is 7.46.

The carbon in Holocene loess deposition is often used to rebuild wildfire history and its evolution process. Through field investigation and the analysis of carbon dust and the magnetic susceptibility index, the earth’s biological sedimentary evidence of wildfire landscape evolution in Holocene is obtained. With reference to OSL/TL dating,¹⁴C dating and archaeology data, wildfire history and landscape evolution process in the loess plateau of Weihe River basin since Holocene is reconstructed. Results show that from the last glacial period to the Middle Holocene stage (12 000-3 100 a B.P.), wildfire changes in loess plateau area of Weihe River basin are mainly associated with regional seasonal climate differences closely, among which the one thousand-one hundred scale effective humidity and fuel supply area change are the main controlling factors of wildfires. In the Late Holocene, with further drought climate, combined with human farming activities, human land use intensity and space-time distribution have become an important driving force to influence of biomass burning scale. Since 3 100 years ago, farmland landscape in the south area of Weihe River has begun to take shape. About 2 170 years ago, the large-scale land reclamation has expanded to the loess tableland area in the north of Weihe River. Until 1 500 years ago, dry farming landscape in loess high order platform tableland areas of northern Weihe River has basically formed. With a number of ancient ecological records and regional point of comprehensive analysis, it helps to understand the region wildfires history, human land use change and evolution of the social structure.

It’s difficult to deal with complex geological conditions in TOUGH2 simulator, therefore, the method of a complex 3D geological model and coupling pattern numerical simulation were put forward, and the authors developed the corresponding program on the Windows platform. It can be used to the geological modeling created by GMS or Petrel software coupling TOUGH2 numerical model. Through the instance of carbon dioxide (CO₂) geological storage, it can be seen that the stratigraphic structure plays a controlling role of CO₂ space migration, the simulation results show that CO₂ can spread along the back slope formation. Therefore, the coupled method,which provides a new approach and methodology to improve the efficiency of this simulator to deal with complex geological structure, such as ups  and  downs stratum, fault, fold and geological attribute of geological body chang according to the space.

On the basic of third-grade tectonic units potential and suitability evaluation results of suitable for carbon dioxide geological storage, learning from siting processes and methods, combining with geological conditions and technical methods level of China, we bring forward that the target scale can be determined by the four major evaluation index as layers of safety, reservoir scale, the ground environment conditions and economic suitability and 44 detailed indexes. The authors still bring forward that evaluation methods, such as the analytic hierarchy process and multi-factors space superposition assessment methods, can be used in the process of selecting target. The authors evaluated the suitability of three typical targets in  Ordos basin and Hetao basin, confirming this evaluation index system has better maneuverability and application value in selecting target.

Owing to the vadose zone evaporation water from the ground surface, finding out the bare soil evaporation rule has important meaning to study some vadose zone water and underwater evaporation problems. To find out the rule of bare soil evaporation intensity in northwest arid inland basin,we analyze the vadose zone cross section water flow features with weather data and calculate the bare soil evaporation intensity adopting the finitedifference method through developing some bare soil water content and vadose zone pressure monitoring site experiments. Express as a result: According to vertical transportation different status of some vadose zone water, the cross section in the bare soil area vadose zone is divided into the vadose zone water upward to transfer zone and the vadose zone water downward to move zone. The extreme limit evaporation depth is 1.2 m in the bare soil zone of Northwest arid inland basin. Subjecting to the external space weather evaporation ability and the vadose zone water upward to transfer ability, the bare soil evaporation inside the basin appears in the second half month of April to the second half month of September, among which the bare soil evaporation quantity in the second half month of April to May is the biggest, and the evaporation intensity reaches to 0.56 mm/d on the average. The percentage of the bare soil evaporation intensity only equivalent to surface evaporation intensity on the average of 3.5%, as biggest as 6.7%.

As for the enhancement of linear Trends, the TRUST method proposed by Smith and O’Connell does not consider the distinctions between the smooth area and other image features. The diffusion is carried on in smooth area and thus inevitably produces artifacts. An improved TRUST method was proposed. The eigenvalues of the structure matrix are reconstructed，so that the method only diffuses the image in specific areas where strong anisotropy is detected. This method is tested on both synthetic and field data sets. The results indicate that the method can be used efficiently to enhance linear structure locally in multiple directions. We have also compared the proposed method with the TRUST method by applying them to the synthetic data set. The results demonstrate that the proposed method can produce better effect with fewer artifacts.

The effectiveness of cross-hole radar tomography depends mainly on the quality of the extracted first arrival-time. Digital image segmentation method, based on the projection onto convex sets (POCS) technique, is used to extract the first arrival-time by segmenting the color image of the energy ratio, and had previously been applied in refracted seismic first arrival-time extraction. We first applied digital image segmentation method into cross-hole radar travel-time tomography to reconstruct the velocity field using an iteratively linearized inversion approach. During the inversion, LSQR algorithm was employed to solve the system of linear equations, Jacobian matrix was constructed by the curved ray tracing technique, and the traveltime was calculated using Multistencils Fast Marching Method (MSFM). We employed a synthetic data set and a field data set to test the effectiveness of the digital image segmentation method in traveltime tomography. For comparison, a traditional energy ratio method is also used for first arrival-time extraction. The result reflected that the tomography based on digital image segmentation method is more accurate with smaller residuals, and can provide more effective judgment for the underground velocity field.

Limited by  the distribution of stations, velocity structures and  the uncertainty of picking arrivals, the precision for the relocation of earthquakes is usually  not sufficient. We collected the data of arrival times recorded by the seismic networks and then used the double-difference method to relocate 1 400 earthquakes occurred in  Haicheng region（39°N-43°N，120°E-126°E）in the last 20 years. Comparing to the original results of the earthquake locations, the results obtained  by the double-difference method in this study  indicate that: 1) The earthquake distributions become more convergent, especially in the region between 40.5°N and 41.0°N and between 122.0°E and 123.0°E, and more consistent with the trend of the fault along the Haicheng-Dayang River; 2) Most of earthquakes occurred in the depth from 5 to 24 km, because there exists a low-velocity and high-conductivity zone in the crust; 3) From the cross sections, many earthquakes distribute as a shape of columnar  along the depth because there exists a comminuted fracture zone which extending from the surface to the depth of 25 km. The root-mean-square travel-time residual  reduces from 0.74 s to 0.26 s  after the relocation using the double-difference method. The study also  indicates that the magnitude is related to the number of earthquakes in this region. If the number of earthquakes increases abruptly, the  probability for the occurrence of a large earthquake increases as well.

Seismic exploration is one of the most effective method on the research and analysis of underground structures. In order to find out the deep structural information of the west of  Liaoning Provience, we emplaced a  deep reflection seismic profile of 16.9 km in the region. As the region’s seismic and geological data is limited,  we carried out a test on  the parameters of deep reflection seismic acquisition  for the obtaining of seismic reflection signals from the deep strata. This test uses dynamite source, 428XL seismograph and SG-10 low-frequency detectors, fixing  acquisition parameters as  sampling interval  1 ms, channel spacing 20 m, and record length 15 s. A more comprehensive experimental work on  the acquisition parameters of motivating factors (excitation depth, explosive dose, combination of well excitation) and receiving elements (combined low frequency geophone) is launched. Based on the seismic records, the authors treat  6.5 s reflected signal as the main reflection layers. By  comparing and analyzing the signal energy and the SNR of the target layers, we  obtain the optimal  excitation and receive parameters as depth 15 m, dose 12 kg; combination of single well and Mitsui; geophone array using dot combinations. The results of the research show that we are able to  obtain deeper reflect information by increasing the exciting depth, the charge, employing combination of well and low-frequency detector and extend recording time etc.

In the field of exploration geophysics, the software packages that can fast and efficiently simulate 2D and 3D seismic full-wavefield, including simultaneously simulate P-wave, S-wave, and surface wave  are not very much.  In the structure mechanics, however, many sophisticated commercial software packages based on the finite element method including ANSYS and PLAXIS for  multi-wave and multi-component have been employed for the solutions of the elastic constitutive equations.  Compared to  the complete elastic wave equations, the elastic ones  include a damping term,  which is a firstorder differential term time. Therefore, by  adjusting  the parameter of  the medium, that is, the Rayleigh coefficient to make the damping to zero, the elastic constitutive equations will degenerate into full elastic wave equation. The wavefields propagating in  the rocks of a  tunnel are free of the disturbance of low velocity resulting from  the cover layer in the conventional seismic exploration. We simulated the wavefields of the tunnel seismic prediction  using the ANSYS software, and researched the  dispersion, damping and absorbing conditions etc. in the numerical modeling. For medium  absorption,  we compared time records and snapshots of the wavefields in the numerical simulation for the cases with and without the damping. In the tunnel seismic prediction, setting the damping to  zero is a reasonable assumption. By comparing  the relation of different grid length and dispersion in the numerical example, we find that the dispersion disappears when the mesh size is smaller than the wavelength of 1/π. By introducing  a viscoelastic boundary condition deduced from the wave equation,  boundary reflections can be effectively absorbed. Finally, an numerical example of the tunnel  seismic prediction shows that the  usage of the ANSYS software can effectively simulate the propagation of  waves in the complicated geological conditions.

As time goes by, the aged satellite sensors have made the original Calibration Parameter File (CPF) of the sensors become invalid. Typically the CPF of the Landsat-5 Thematic Mapper (TM) was modified several times since its launch in 1984, and so did the CPF of Landsat-7 Enhanced Thematic Mapper Plus (ETM+). Otherwise the accuracy of the image radiometric correction is not ensured. In this study, two scenes of Landsat TM and ETM+ images have been corrected using their CPFs issued in 2003 and 2009, respectively. These radiometricallycorrected images were then compared to see whether there was any difference between the correction results. The band-by-band comparison reveals that, except the green band of ETM+, the mean value of TM and ETM+ bands calculated with the 2009 CPF is less than that calculated with the 2003 CPF. This also has influenced on the Normalized Difference Vegetation Index (NDVI) and buildup index (IBI) computation. The difference in the mean value between the NDVIs calculated using the 2003 and 2009 CPFs amounts to 0.48%, while this figure between the IBIs can reach to 5.94%.

The heavy metal elements contents in stream sediments provide the evidences for evaluating the soil-contaminated degree in the mining area. And they are also used to predict the potential of the mines. Based on adsorption mechanism of hydroxyl groups in the stream sediments and free positive ions, in-situ hyperspectral measurements are analyzed to make sure that the best relevance between the soil spectral variables and soil heavy elements concentrates is on the wavelength of 500-780 nm and 2 100-2 300 nm. Thus the regression equations for the field spectral features and metal element concentrations are determined to estimate the heavy metal element contents. The inverse distance weighting method is employed to retrieve the heavy metal contents, Cu and Zn, in stream sediments successfully. And the R² of Cu is 0.618 and the R² of Zn is 0.636. The results show that the heavy metal elements contents in the mountain and forest regions are lower than what in the middle reaches of the streams and the content has a rising trend along the river flowing direction. Furthermore, there exists a high-value anomaly zone in the middle and lower reaches, which provides the evidence for future investigation.