Yellow River is the second large river in China and it is also famous in the world as the abundant sand river. The ecological-environment is very fragile in Yellow River Basin due to soil sali-nization and disastrous sandstorms on the upper reaches, soil erosion on the middle reaches and the “Hanging River” on the lower reaches which induced the calamity of flood, water logging, running dry and drought. Because of rather lack of water and water quality problem in the basin, quantities of water resources were calculated and balance of water supply and demand in counties and cities as well as the potential capacity of groundwater development were predicted. Base flow separation method and isotope technique were adopted to study the cyclic relationship between river water and groundwater. Finally, the renewable capability of groundwater resources and the ways of groundwater sustainable development and utilization in Yellow River Basin were probed.

Geophysics is a multi-discipline subject involving many aspects which have quickly deve-loped in the 20th century. It had greatly contributed to the progress of science and technology and the development of society and economy in the past hundred years. The geophysics in the 21th century is facing both opportunity and challenge. However, as it developed swiftly in the world the “crisis” of geophysics in China has emerged.We must realize the connotation of geophysics as a whole, strength the overall construction of geophysics subject and settle the essential and guide effects of geophysics from the viewpoint of development of systemic geosciences. Several problems are discussed as follows:(1) the development progress and the strategic significance of geophysics;(2) summary of the main great achievements of geophysics in the 20th century;(3) main contents in geophysics research;(4) the guide and task of geophysics in contemporary China;(5) the challenge and opportunity faced of geophysics in China;(6) the trend of geophysics at the present in China;(7) sincere suggestions.

A new species Sphenobaiera junggarensis sp. nov. from the Middle Jurassic Xishanyao Formation in western Junggar Basin of Xinjiang, China, is reported for the first time. The new species is characterized by its cuticles in which it is amphistomatic in type, stomata are few in upper cuticles and much more in lower cuticles with basically longitudinal in orientation, ordinary epidermal cells have irregularl cutinized domes on surface and guard cells possess finely comb-shaped cutinizations between the contiguous cutinized radial striations on the outer fringes. The authors also discusse the significance of the new species of Sphenobaiera in its taxonomic and paleoclimatic studies.

Ages of some Palaeozoic stratigraphic units in Southern Mongolia are revised by means of conodont study. The Arynshand Formation should be the Early Carboniferous. The upper part of the Gavuu Member of the Mandalovoo Formation near the Bayan-Khoshuu Ruins section in the Mushgai area is definitely the earliest Devonian; a new stratigraphic unit, the Olonovoot Formation, is suggested for this part. The upper part of the Tsagaanbulag Formation at the Tsakhir Section and the Ulaan-Shand Section should be assigned to the Lochkovian rather than Silurian. The Chuluun Formation is actually late Emsian, and the Tsagaankhaalga Formation is Early Eifelian. The Indert Formation is Early Carboniferous.

The volcanics of the Upper-Silurian Bayinbuluke Formation in the northern part of the Southern Tianshan are mostly intermidiate-basic in composition, are associated with gabbro and contain abundant pyroclastic rocks. The Zr/Nb values (26~47, averaged 37), Hf/Ta values (11.9~19.9, averaged 14.8) of the volcanic-magmatic complexes indicate that, similar to the N-MORB, they have a depleted mantle derivation. Their (La/Yb)_N values range from 2.92 to 5.21) and Nb/La values from 0.22 to 0.33, averaged 0.29, showing that they are enriched in LREEs and LILEs and depleted in HFSEs(especially with apparent negative Nb and Ta abnormalies), features similar to those of the island arc magmatic rocks and an apparent indication of formation in island arc setting. In space, the Bayinbuluke Formation is near an ophiolitic mélange belt on the southern margin of the Central Tianshan; in time, these strata almost have similar age as the subducting age of the Southern Tianshan Ocean. Thus, it stands a good chance that the formation of these volcanicmagmatic complexes owes to late-Silurian subduction of the Southern Tianshan Ocean.

The Solonker-Linxi suture marks the final closure of the Central Asian Ocean (also called it Paleo-Asian Ocean), and is a suture boundary between the North China and Siberian blocks. A comparative analysis of paleomagnetic data from the North China and Siberian blocks has been done to determine the collision and amalgamation history of two blocks in the central Asian region, and corresponding time of final closure of the Central Asian Ocean, located between two blocks. The results show that (1) The Central Asian Ocean separating the Siberian and North China blocks was likely opened further from the Late Devonian to the Late Carboniferous. The Central Asian Ocean reached its greatest width of about 39 in latitude in the beginning of Early Permian; (2) The Siberian block began to drift southwards rapidly in the Early Permian, and collided with the North China block at the end-Permian (~250Ma), leading to the formation of the Solonker-Linxi suture.

Quite a few gold deposits have been found recently in the southern Sonid Zuoqi, Inner Mongolia, such as the Bayan Bold, Bayan Har and others. The Bayan Bold gold deposit is located to the north of the Sonid Zuoqi ophiolitic melange belt, and the Bayan Har gold deposit is in the west of the belt, which is thought to be a part of the Sonid Zuoqi-Hegenshan suture zone between the southern margin of the Siberian plate and the northern margin of the North China plate. Based on a comprehensive study, the authors hold that there are two genetic types of gold deposits in Sonid Zuoqi. The Bayan Bold gold deposit, which is related to granite-porphyry formed in Early Paleozoic island arc environment, is of a mesothermal type. And the Bayan Har gold deposit, which is related to the granite-porphyry intruded in Sonid Zuoqi ophiolitic melange belt in the middle-late stage of the Late Paleozoic, is of an epithermal type.

The Fuwan superlarge silver deposit is hosted in the Early Carboniferous limestones along a contact fault zone between the limestone and the overlying Changkeng Au-hosting siliceous rocks. The ⁴⁰Ar-³⁹Ar age of the ore-related quartz veins from the Fuwan silver deposit is （64.3±0.1） Ma. The silver deposit is characterized by high μ values (10.67~10.95) in Pb isotopic composition, being much higher than those of the Paleozoic ore-hosted strata and being similar to those of ores hosted in Preterozoic metamorphic base in the Western Guangdong Province. It is concluded that the ore-forming material of the superlarge silver deposit came primarily from the Proterozoic basement. The superlarge silver deposit owns its origin to the Himalayan volcanic activities in the region of the Sanshui Basin.The formation of Fuwan superlarge silver deposit is controlled by the following favorable geological conditions: The intersection of deep faults and contemporaneous faults at the margins of the Sanshui Basin served as excellent passageways for ore fluids; the special ore-hosted rock association served as the ore-concentration and ore-trapping structures; the silver-rich basement，multiple stages of mineralization and of mobilization of silver and related elements; geothermal convection system related to multiple episodes of volcanic activities.

He and Ar isotopic components of the fluid inclusions in pyrites from the main tin deposits in the central Nanling region are studied to discuss the genesis and material sources of these deposits. The results indicate that the ⁴⁰Ar/³⁶Ar ratio varies between 288 and 371 and ³He/⁴He 0.09~28.58 Ra. He and Ar concentrations change greatly in different area while ⁴⁰Ar/³⁶Ar and ³He/⁴He ratios are more consistent in the same area.⁴⁰Ar/³⁶Ar ratios are between that of the atmosphere saturation water(including meteoric precipitation and seawater)（⁴⁰Ar/³⁶Ar≈295.5）and that of Hawaii hotspot（⁴⁰Ar/³⁶Ar=350～360）; Their ³He/⁴He ratios are apparently above those of the continental crust（³He/⁴He≈0.03Ra） and are within the range of the averaged crust, of the primitive mantle（³He/⁴He≈8.57 Ra） and of the characteristic Hawaii hotspot（³He/⁴He≈27.14 Ra）. Above features indicate that the metallogenic fluids are related to the activation of the mantle plume, and they probably are the mixing product of the mantle-and crust-derived fluids and of the meteoric water. The results provide new evidences that the tin deposits are product of the crust-mantle interaction and that the mantle plumes had existed in the Nanling region.

Based on the research on the metallogenic setting and on the mine geology of the Tuanjiegou gold deposit, a synthesis exploring model for the deposit has been set up. The characters of synthe-tical exploring information about the area have been summarized according the geological information, high precision magnetic measurement, γ-ray spectrum testing and geochemical information of soil carried out and the concealed gold orebodies have been forecasted. By compared to the synthetical exploring model of the Tuanjiegou gold deposit, the most favorable targets for the concealed orebodies were selected and tested. Gold ores were found in both exploratory trenches and shafts, and gold ores with 1.5t gold have been proven. It proves that the present forecasting efforts are successful and there is great potential also for gold searching around the Tuanjiegou gold deposit.

Based on the detrital model of sandstone proposed by Dickinson and Suczek et al.，the characters of the detrital composition of the Mesozoic sandstones at the southern margin of the eastern Qinling and Dabie orogenic belt are studied to determine the type of their source areas. it seems that most Mesozoic sandstone were derived from the eastern Qinling and Dabie orogenic belt，from the Longmen mountain and from the Jiangnan thrusting nappe belt, with features of the recycled orogenic belt. The variation sequence of the detrital composition should be the sedimentary response to the three episodes of large scale of thrusting of the orogenic belt surrounding the basins. Through analysis on the tectonic significance of the detrital composition of Mesozoic sandstone，the authors discuss the coupling between basin and mountain and the tectonic evolution during Mesozoic in the eastern Qinling and Dabie orogenic belt.

Lindian fault depression of the Songliao Basin is composite in basin structure, which can be divided into slope-fault terrace zone, depression zone and fault uplift zone. Those sub-structural units controlled the contributions of provenances, stream systems and depositional areas, and also controlled the development of depositional systems and their types. The fault terrace zone controlled the occurrence and distribution of sand deposits, developing alluvial fan-fan delta system on the steep slope fault terrace and alluvial fan-fluvial-delta on the gentle slope fault terrace. The fault uplift zone was a drainage divide within the fault depression, developing fluvial-delta systems on its two sides. The hanging wall area of fault can be used not only as depositional area, but also as bypass for the sediments to the center area of deposition. The depression zone was controlled by a single fault or a couple faults, developing fine sediments of shore swamp and shallow lake, being a kind of source rock.

The reservoir features of second member of Jurassic Sangonghe Formation in Moxizhuang area of Junggar Basin, have been studied by various means. The results show that reservoir rocks have relatively low composition maturity and high geometry maturity. Porosity of the reservoirs mainly belongs to very low to middle standard and permeability mainly belongs to extremely low to middle standard. The oil-bearing condition of reservoir is mainly controlled by permeability when porosity is high to 10%. Main pore types are primary intergranular pore, corrosionmodification intergranular pore and intragranular corrosion pore. Pore family is dominated by special large pore and throat family is dominated by micro-throat. Diagenesis types are compaction, cementation, alteration and replacement, and diagenesis stage is at A sub-period of late diagenesis period. Compaction and cementation cause reservoir porosity decreasing about 24.5% and corrosion causes reservoir porosity increasing about 4.5% during the diagenesis period.

Facies sequence of volcanic rocks is predominantly controlled by lithotypes in the Songliao Basin. Acidic eruption cycles generally begin with explosive facies and end with extrusive facies. Andesitic/basaltic eruption cycles usually begin with effusive facies and end with volcanogenitic sedimentary facies. Interbeded acidic-intermediate-basic volcanic eruption cycles have complex facies sequence ge-nerally from effusive facies through explosive facies to volcanogenitic sedimentary facies. Weathered crust and sedimentary intercalation are indicative of volcanic intervals. Extrusive and volcanogenitic sedimentary facies are the end-members of an eruption cycle. Facies model described here has been effectively used in seismo-reservoir interpretation in the gas field of volcanic rocks of the Songliao Basin. Only four of the 15 volcanic sub-facies can form high-quality volcanic reservoirs, which include volcanic neck, pyroclastic-bearing lava flow, upper effusive and inner extrusive sub-facies. Well understanding about volcanic facies can make gas exploration easier and more effective: volcanic reservoir exploration → effective reservoir finding → focusing on seismic analytic interpretation of the best four types of volcanic sub-facies which can become potential good reservoirs.

Quantitative grain fluorescence technique is for the first time applied in study of Silurian palaeo-oil pools distribution in the Central Tarim Basin. Much attention was put on discussion of possibility of vertical superposition and horizontal continuity of small pools to form a large-scale palaeo-oil pool. The results show that there weren’t large-scale moveable oil pools superposed and connected with same palaeo-oil-water contact, while all the small oil pools distributed separately in the single local structures. In geological periods, oil pools were formed in the 1st sub-member of upper member of Kepingtage Formation in well-Tazhong 4 and well-Tazhong 17 areas, but they were destroyed later on. In the 3rd sub-member of this upper member in well-Tazhong 117 area and the 1st sub-member in well-Tazhong 31 area, oil pools were only formed in the later oil accumulation stage. In the 1st sub-member in Tacan 1 well area, a large pool came into being in the first oil accumulation stage, but without oil charging in later stages. The results also indicate that Silurian reservoirs are good for oil & gas migration so that plenty hydrocarbons migrated through them in geological stages. The central fault belt in the Tazhong uplift are thought to be the favorable locations for oil accumulation, so it should be taken into consideration in future Silurian exploration.

There are six types of association and three physical facies patterns of organic fluid inclusions traped in the rocks of Triassic and Jurassic in West Sichuan. Their compositions, which were detected with Laser Raman microspectroscopy, include CH₄,C₂H₂,C₂H₄, C₂H₆, C₃H₈,C₃H₆,C₄H₆,C₆H₆,CO₂,H₂,H₂S and CO. The fluid inclusions can be divided into four stages based on their homo-genization temperature, salinity, burial history and thermal history. In the studied area, organic inclusions were formed in different phases of generation, migration and evolvement of oil and gas and the different stage of diagenesis. All of these features can be used as key indicators of reservoir formation.

By means of the gold tube thermal simulation equipments, 2 oil samples from Tarim Basin are carried out pyrolysis under high pressure and constant heating rate. Combining GC and carbon isotope analysis, the relationship between generation ratio of and carbon isotope ratio of methane and simulating temperature along with heating rate can be obtained. Based on the experiments above, the chemical kinetic models of methane generated from oil and its fractionation of carbon isotope are constructed and calibrated. The results indicate that the average value and distribution range of activation energy of methane generation are similar for the two oil samples with insignificant difference in distributional manner. The average activation energy of ¹²CH₄ generation is a little bit lower than that of the corresponding ¹³CH₄ because of relatively higher in low part of activation energy distribution of ¹²CH₄ compared to that of ¹³CH₄. There is a tiny difference between the activation energy distribution of ¹²CH₄ and ¹³CH₄ gene-ration that results the obvious fractionation of carbon isotope of the methane generated. The initial application of the calibrated models in Tarim Basin suggests that the gas pools in well Yingnan 2 comes mainly from the partial accumulation in late-and recent-period, and that of well Mandong 1 is cumulated gas.

The accuracy of ¹⁴C age correction mainly depends on the identification of the factors affecting the variation of ¹⁴C activity in the process of formation of dissolved inorganic carbon and its evolution. Yinchuan plain has been taken the as case study and mass equilibrium reaction model and isotope mass transfer model have been employed to simulate the inverse geochemical reaction path of deep groudwater in Yinchuan plain and then to correct ¹⁴C age. The simulation result shows that the main reactions controlling the geochemical evolution of confined water from the initial point to the final point in the groundwater flow path are the dissolution of plagioclase,horn blende,gypsum, Ca-Na exchange and the precipitation of carbonate minerals. The above reactions have little effect on the transfer time in the groundwater flow path. ¹⁴C correction result shows that deep groundwater in Yinchuan plain is paleogroundwater with ¹⁴C age more than 2 000 a except in the recharge area and the circulation rate is very slow and has low renewing capacity. Outside the depression cone of deep groundwater, the age of deep groundwater is becoming older along the groundwater flow path.However, in the depression cone,the age of deep groundwater is younger than the incoming water,which signifies that there is a close hydraulic relationship between deep groundwater and shallow groundwater.

In two-dimensional profile,the resultant of the static lateral pressure on both sides of anti-slide piles are not equivalent and not in the same horizontal line because of the difference of scale and shape of slope, which will directly affect the flexural torque and shear of resistant pile. There are two effects of whole sliding and laterally swelling for the gliding mass under the action of gravity.When the dipping angle of the slide surface is slow, the lateral swelling will be predominant, which implies that load designing should depend on the difference of resultant of static lateral pressure on both sides of antisliding pile; When the dipping angle of the slide surface is steep, the whole sliding will be predominant, which implies that load design could be determined by classical slice methods. Furthermore, it is shown that numerical simulation is a powerful tool to calculate static lateral pressure with a case study by the finite element method.

In order to evaluate the sensitivity to alkali-saline land in the West of Jilin Province with the fragile eco-environmental problems, 6 395 cells had been divided with the help of the polygon over-laying method of GIS and 6 indexes were chosen. The degree of sensitivity had been divided into non-sensitivity, low-sensitivity, high-sensitivity and the highest-sensitivity. The AHP model was used to ascertain the weight of evaluating indexes, and the Fuzzy model was used to evaluate the level of sensitivity to alkali-saline land,which could supply the useful basis to the division of the sub areas and visualization of result by GIS technology.The result showed that the above methods could improve the precision of evaluation. The alkali-saline land in the West of Jilin Province is dominated by highsensitivity. The low-sensitivity and the nonsensitivity were take second place, and the highest-sensitivity was the least.

The adsorption thermodynamic characteristics of Pb and Cd onto natural biofilm, suspended solids and sediments collected from Songhua River were firstly investigated. The adsorption capacity of these three adsorbents was compared on the basis of adsorption thermodynamics parameters and the reasons of difference of adsorption capacity were also discussed. The results indicate that the classical Langmuir and Freundlich adsorption isotherm can be used to well describe the adsorption thermodyna-mics of Pb and Cd. The decreasing order of adsorption capacity of three adsorbents is in the decreasing order of biofilm, suspended solids and sediments and the adsorption capacity of Pb onto these adsorbents is significantly higher than that of Cd.

About 250 km gravity-magnetic profile data were obtained in Chaoshan depression in the Northern part of southern China sea for the first time. The crust structure of Chaoshan depression was studied, the distributions and attributes of the volcanic rock was analyzed qualitative. Based on Euler deconvolution, the position and depth of the source of gravity fields was estimated, the northern margin faults of continental slope and Dongsha faults was divided. According to dissecting depth of the zone of faults, the two zones of faults with upwelling of magma were transcrust (crust-upper mantle zone of faults). The depth of Moho-surface was calculated by Parker-Oldenburg inversion. Using moving average of logarithmic energy and men-computer mutual system, the depth of magnetic basement was inversed.The results shown that the depth of Moho-surface in Chaoshan depression was uplifted gradually from northwest to southeast direction, the beginning poing was about 25km deep, and the end point was 14 km deep.The depth of magnetic basement was deepen gradually from the start station 3.6 km of the measuring line in northwest direction to the end station 8.9 km of the measuring line in the southeast direction.

Recent years, to improve seismic prospecting records and increasing signal-to-noise ratio, some filtering techniques have been presented, such as the chaotic vibrator method (CVM) based on chaotic theory, the hyperbolic time-distance relation filtering (HTDF) based on the least-squares algorithm, the time-frequency peak filtering (TFPF) based on the time-frequency analysis and Wigner-Ville distribution, the technique decreasing multiples based on independent component analysis (ICA). The CVM is applied to ascertain the location of events with strong random noise. The HTDF is the processing technique following CVM to obtain a clear event recovery from the seismic prospecting records corrupted by random noise. Tests of these methods on both simulation experiments and practical seismic data processing show that the TFPF technique can successfully decrease the random noise. The technique to attenuation multiples based on ICA can differentiate the output signals. However, above four techniques have still some questions which require to be solved, such as the computation efficiency, the assistant processing, the supplement-frequency method of amplitude spectra of the filtering factors, the adapting time-window technique, the systematism of processing performance and so on. Above processing techniques are a part of theory and method in seismic data processing.

Two types of methods are usually used for solving problems of numerical modeling of acoustic scattering. One consists of the methods based on grids, and the other on integral equations. When the model has a large scale, both types of the methods become difficult to be implemented because of the shortage of the computer storage. Furthermore, in the methods based on grids, near the source point both the source position and the computation accuracy are limited by the grid used, and thus cannot meet the demands of practical applications. To solve these problems, this paper presents two new schemes for numerically treating acoustic scattering problems. In these two schemes, one is for grid methods and the other for integral equation methods. In the scheme for grid methods, the original modeling problem of total field is transformed into the one for scattered field, by means of splitting the total wavefield into the background and the scattered wavefield. Since the background field can be computed analytically, the source can be located at any point that does not need to be a grid point. Because of the same reason, the singular property of the wavefield near the source point can be treated analytically. In the scheme for integral equation methods, by means of introducing the quasi-linear approximation, the field computation needs no longer to be realized by solving large linear equation systems. A numerical integration is enough. The schemes presented in the present paper can be used for solving general problems, and their basic ideas can be directly used for treating elastic scattering problems as well as for establishing schemes for velocity and density inversion.