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    20 March 2005, Volume 19 Issue 3
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    Engineering Geology and Environmental Geology
    Characteristics of the Early Proterozoic Volcanic Rocks and Its Dynamic Background of Formation in the Liaodong Area
    WANG Yi-fen, XU Gui-zhong, SHE Hong-quan, SHI Tie-zheng
    2005, 19(3):  315-324. 
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    The Early Proterozoic volcanic rocks of the Liaodong area are the important part of composition of Lower Proterozoic Liaohe Group. They are composed of two suites of the acid and basic volcanic rocks. It is suggested that the former should have been formed during the early-tensile depressing stage of the Liaohe rift development, which belongs to the melted crustal magma; the latter should have been formed during the mid-late intensive depressing stage of the Liaohe rift, which belongs to mantle-derived magma. This paper deals mainly with the characteristics of the petrology, mineralogy, petrochemistry and geochemistry for the basic volcanics. The above result has indicated that these volcanic rocks are mainly a suite of eruptive pillow basic lava from the sea-floor, which have the characteristics of the continental and oceanic tholeiites and belong to the evolutionary products of the Liaohe rift from continental crust to oceanic crust. It is thought that the dynamic background of the formation for volcanic rocks is closely related to the occurrence of the hot-mantle convection and the translational activity of the right-lateral shear of the Tan-Lu fault zone during the Early Proterozoic Era.

    he Forming and Evolution of Chenglang Fault, Northern Jiangxi: Evidences from Geochemical Analyses of Chenglang Ultrabasic Dykes and Xingzi Granites
    WANG Chang-liang,CONG Wei-ke,YAN Dan-ping,ZHOU Mei-fu,DONG Tie-zhu
    2005, 19(3):  325-333. 
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    Penglu and Zhanggongshan micro-blocks occurred in the Huanan orogenic belt, which separated the Yangtze Plate from the Cathaysia Plate.The Chenglang fault separated the Penglu micro-block to the west from the Zhanggongshan micro-block to the east. However, when and how the Penglu and Zhanggongshan micro-blocks joined together still leave unsolved.Samples from Pre-cambrian granites in Xingzi metamorphic dome which were nearby the Chenglang fault zone and ultrabasic dykes intruded along the Chenglang fault were collected and analyzed with ICP-MS methods.Variable trace element discrimination diagrams indicate a continental environment for Xingzi granites and volcanic-island arc environment for the ultrabasic dyke.The formation of structural styles and geochronological data suggest a volcanic arc formed between the Zhanggongshan and Penglu micro-blocks, and this volcanic arc was produced by the northwestward subduction of Zhanggongshan micro-block underneath the Penglu micro-block. It is inferred that where after the collision of the Yangtze and Cathaysia plates, formed the Huanan orogenic belt, and involved in these earlier micro-blocks.

    Characteristics and Evolution of Progressive Metamorphic Belt in Chonghuer of the Altai Area, Xinjiang
    XU Xue-chun, ZHENG Chang-qing, ZHAO Qing-ying
    2005, 19(3):  334-340. 
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    The two stages of regional metamorphism are developed in  the Altai area of Xinjiang, of which the first is characterized by the regional low-temperature dynamic metamorphic type, and the second is represented by the regional dynamic heat flow metamorphic type.The progressive metamorphic belt of   the Chonghuer area belongs to a part of the second stage of metamorphism.The staurolite-kyanite belt, biotite-garnet belt, chlorite-biotite belt and sericite-chlorite belt developed respectively from the center of volcanic sedimentary basin to margin, representing progressively decreasing in metamorphic grade.The metamorphic process is divided into three stages of early episode, peak episode and late episode according to the feature and evolution of metamorphism and deformation.The both of early episode and peak episode are a continued metamorphic process, forming a typical mid-pressure type progressive metamorphic belt.The late episode is a regressive metamorphic process.The geodynamic process of metamorphic evolution shown a clockwise p-t path,  representing a specific tectonic condition and the earth crustal evolution regime of Hercynian orogenic belt in the Altai area of Xinjiang.

    The Foundation of the Precambrian Yadong Rock Group and Its Characteristics in the Yadong Area, Southern Tibet
    ZHANG Xiang-xin，LIU Wen-can，ZHOU Zhi-guang，ZHAO Xing-guo，LIANG Ding-yi
    2005, 19(3):  341-347. 
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    The Precambrian crystalline rock series in the Yadong area is previously called “the Nyalam Group”. However, it can be divided into two parts, which are angularly discordant with each other, and they are different in the rock association, metamorphism and deformation characteristics, and formation age. The lower rock series is established as a new formation named the Yadong Rock Group, whose rock association is the following: the lower part consists of  many kinds of gneisses intercalated with a minor amount of fine-grained quartzite and biotite schist ; the middle part consists of many kinds of migmatites; the upper consists of gneisses intercalated with a minor amount of leptynite, quartzite, and schist.The Yadong Rock Group contains deep-dervied enclaves such as pyroxenite, hornblendite, and granulite, which are never found in the Nyalam Group.In the light of the metamorphic and tectonic analyses, the Yadong Rock Group underwent the metamorphism from amphibolite facies to upper amphibolite facies, and many stages of plastic deformation of deep tectonic level, as is different from the Nyalam Group.The argument that the Nyalam Group represents the whole Precambrian strata in the Himalaya area is worth discussing.

    Experimental Study on Synthesis of Tobermorite by Decomposing Potassium Feldspar
    QIU Mei-ya, MA Hong-wen, NIE Yi-miao, ZHANG Pan, LIU He
    2005, 19(3):  348-354. 
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    Potassium feldspar was hydrothermally decomposed at low temperature and low pressure with CaO as additive, and then to synthesize a calcium silicate hydrate, i.e. tobermorite, meanwhile dilute KOH liquor was produced which could be used to prepare highly pure potassium carbonate.The factors affecting the crystallizing reaction include the mole ratio of Ca/(Al+Si), reaction temperature, reaction time, weight ratio of liquid to solid, and the rate of stirring. The experiments demonstrate that the process of decomposition of potassium feldspar and then synthesis of tobermorite are feasible, and the technique is near 100% in availability of the insoluble potassium resource From the experiments the optimal technical parameters are as follows: the temperature is 200-250 ℃, the mole ratio of Ca/(Al+Si) is 0.8-1.0, the reaction time is 5-8 hours, the weight ratio of liquid to solid is 20-25, and the rate of stirring is 400 r/min. With increasing temperature, the decomposing rate of potassium feldspar is enhanced.The higher value of Ca/(Al+Si) is propitious to the decomposition of potassium feldspar. The decomposing reaction can complete in 5-8 hours.The results indicate that the decomposing rate of potassium feldspar is over 80%, and the needle-like shape tobermorite is well synthesized in the experiments.

    Mechanism of Chrysoberyl and Alexandrite Color
    LUO Hong-yu，PENG Ming-sheng，LIAO Shang-yi，GAO Li-sheng2
    2005, 19(3):  355-360. 
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    Twenty four chrysoberyl and alexandrite samples from the major deposits all over the world were studied qualitatively by XRF and the trace elements in chrysoberyl were gotten mainly to be Fe, Ga, Ti, in alexandrite to be Fe, Cr, Ti.Half quantitative analysis of SRXRF experiments were carried out on one chrysoberyl and one alexandrite, the results indicated that in chrysoberyl Fe concentration averaged to be 17,800×10-6, Cr 855×10-6; in alexandrite Fe concentration averaged to be 16,060×10-6, Cr 13,333×10-6; and Ga was one of the very important impurity in chrysoberyl only less than Fe concentration Optical absorption of 15 samples indicated that the absorption of chrysoberyl was induced by Fe3+ ion, of alexandrite by Fe3+ and Cr3+ together.Series chromaticity calculations were processed. The calculation results indicated that the optical spectrum which had the 540-630 nm broad absorption band and the 440-470 nm maximum absorption would induce red to green colorchange alexandrite effect, so the treatments of alexandrite may work in the direction of getting such a visible spectrum.

    Geological Characteristics and Controlling Conditions of Non-metal Deposits in Continental Volcanic Sedimentary Rock Series
    LI Guang-you
    2005, 19(3):  361-368. 
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    Non-metal deposits are commonly found in continental volcanic sedimentary rock series in the coastal area of China, which were formed during Jurassic and Cretaceous. They usually occurred as stratiform orebodies or stratiform-like orebodies with relatively stable thickness and grade along volcano-sedimentary sequence, not affected by faults nor by subvolcanic intrusions. In the same area, these are several metallogenetic cycles closely related to ore-bearing structures and volcanic apparatus. Ore-bearing rocks are sedimentary volcanic pyroclastic rocks altered by aqueous or hydrothermal solutions and indicated by typical structures, such as quench-cracks of quartz, ripped vitroclastic in the matrix, as well as change in chemical compositions, so they are different from ‘dry’ volcanic pyroclastic rocks formed on land. The controlling conditions of non-metal deposits are as follows: mineralization temperature is about 50-100 ℃; pressure is below n×105 Pa; pH value varies from one type to another and increases in the following sequence: alunite→kaolinite→pyrophyllite→illite→bentonite →zeolite, from acid to alkali.Bring into and leaching out of rock-forming components can be found. Ore-bearing minerals account for about 30%-50% or above.

    Metallogenetic Characteristics and Material Source of Zoujiashan Uranium Deposit，Jiangxi Province
    ZHANG Wan-liang，LI Zi-ying
    2005, 19(3):  369-374. 
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    Zoujiashan deposit, located at the west of Xiangshan volcano-intrusive complex, is a typical hydrothermal vein-type uranium deposit, which is governed by Zoujiashan-Shidong fault and its induced tension or tenso-shear fracture zones. The vein- and lens-shaped ore bodies are in group and in zone.The wall rock alteration can be divided into two epochs.The early epoch is characterized by alkalic replacement with albitization, apatitization, and carbonatization, and the late is acid alteration with fluoritization and hydromicazation.The evolution characteristics that both the acidity and δ18O of the ore-bearing hydrothermal fall gradually from the early epoch to the late, are similar to those of other typical porphyry deposits.The coexistent relationship between U and Th in ores, and the similar REE patterns of uraninites, ores, granite-porphyrys and clastoporphyritic lava indicate that ore-forming materials, as granite-porphyrys and clastoporphyritic lava, originated from the deep magmatic system.They are of the same source.

    The Geological Characteristics of the Massive Sulfide Pb-Zn Mineral Deposits in the Central Fujian Rift and Its Implications for Deposit Exploration
    ZHANG Sheng-hui, SHI Jian-ji, DI Yong-jun, YU Xin-qi
    2005, 19(3):  375-384. 
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    Investigations on the paleo-tectonic setting, major characteristics and origin of deposits in central Fujian Province are key parts to a better understanding of the Precambrian tectono-magmatic evolution and further ore explorations in the Cathaysia Block. The stratigraphic sequence and petrography indicate that the Dongyan Formation of the Mamianshan Group underwent at least three generations of bimodal volcanism instead of the result of one period of volcanism.Geochemical analysis suggests that the protoliths of the Dongyan Formation, host strata of the major deposits, were marine spilite-quartz keratophyre series, which resulted from the continental rifting during the Meso-Neoproterozoic. Detailed analyses on the typical deposits reveal that the massive sulfide deposits or mineralization embryos were formed by seafloor volcanic exhalation in Neoproterozoic. These deposits underwent tectonic deformation and magmatic-hydrothermal superposition in later Mesozoic and led the formation of some deposits. Based on the research mentioned above, the relationships between the origin of the massive sulfide deposits and the Meso-Neoproterozoic rifting tectonic settings are discussed.The geologic features and markers which could be used as clues for deposit exploration have been summarized and the favorable prospecting regions are discussed.

    Paleo-structure Reconstruction and Its Application to Paleographic Reconstruction in Foreland Thrust Belt：A Case Study of the Upper Paleozoic in the West Margin of Ordos Basin
    WANG Ze-cheng，ZHAO Wen-zhi，CHEN Meng-jin，YIN Ji-feng，WANG Chao-yong
    2005, 19(3):  385-393. 
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     Lithofacies paleogeographic mapping is a key to paleogeography reconstruction.The mapping has various interpretations in foreland areas because of strong deformation, strata hiatus, facies-break and pseudomorphs of paleo-uplift.This paper puts forward a five-steps method to reconstruct paleo-structure in the foreland areas.First, it is necessary to reconstruct structures at 3 key stages: pre-depositional, syn-depositional and post-depositional paleo-structures.Secondly, the distribution and mapping of sedimentary systems should be studied in isochronous stratigraphic framework by the integrated analyses of drilling, log and seismic data.Thirdly, the source area analysis is a tie of distribution of sedimentary systems between basin and orogenic belts.Fourthly, the original strata distributions are restored by reasonably choosing reference points. Finally, the reasonable lithofacies and paleogeographical mapping can be made after all these works mentioned above. This paper takes the Permian Shanxi Formation and Xiashihezhi Formation in the west margin of Ordos Basin as examples to reconstruct lithofacies paleogeography on the basis of paleo-structure restoration and source area analyses by the above five steps.The study  shows that there was a slide-tension fault depression in the north of west margin of Ordos Basin at the early and middle Carboniferous periods, there were three source areas at the Permian period, and the Mesozoic thrusting resulted in 20% to 47% strata shortage. The distribution of sedimentary systems and sandbodies after the restoration of lithofacies and paleogeography differs greatly from that before the restoration, and this will be significant to guide the Upper Palaeozoic gas exploration in the west margin of Ordos Basin.

    Sedimentary Environment and Provenance of the Guanjiagou Formation of the Western Qinling Mountains  
    LU Hai-feng, WANG Zong-qi, WANG Tao，JIANG Chun-fa
    2005, 19(3):  394-402. 
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    Sediment association of the Guanjiagou Formation is characterized by increasingly coarsening upwards sequence.The lower of the Guanjiagou Formation is typical turbidity current deposit, which consists mainly of mudstone and sandstone. Its grain-size changes coarse upwards and the conglomerate stratum becomes thick in the middle part.The upper part is thicker conglomerate with lamella massive sandstone.The content of gravel in conglomerate and granularity increases and augments respectively. By study, the Guanjiagou Formation is marine sediments which were showed by the fossil.Therefore, it is deduced that the Guanjiagou Formation is submarine fan.The geochemistry characteristics of siltstone and slate show that the values of La, Ce, ΣREE, δ（Eu）of the Guanjiagou Formation are similar to those of island arc. By the tilted lay of stratum, the excellent trend of gravel and the change of gravel in orientation ,the current of the Guanjiagou Formation is analyzed synthetically and it is deduced that the direction of paleo-current is about 230° to 356°, and most is west-north; while the gravel excellent trend is 228° to 338°, most north-northwest. From south to north, the size of gravel becomes small gradually, gravel round increasing, and gravel excellent trend is from disorder to order by field statistic.With previous results, the Guanjiagou Formation is in Bikou forearc basin and it is presumed that the sediments were from east-southern island arc.

    The Analysis on the Characteristics of Early Origin and Multi-period Forming of Lithologic Trap: Case Study of Erlian Basin， Inner Mongolia
    LIU Zhen, LIANG Quan-sheng , XIAO Wei, DANG Hu-qiang
    2005, 19(3):  403-408. 
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    According to the critical condition of reservoir and caprocks, the article makes use of the evolution curves of caprock entry pressure and reservoir porosity to fix the forming depth of the lithologic traps, and at the same time proves that the lithologic traps can form in several formations. If the entry pressure of caprocks and reservoir characters regularly evolute in accordance with the nowadays evolution curve, we can deduce that lithologic traps can form in early time and the traps have several forming periods.The realistic data of Erlian Basin prove that lithologic traps have the characteristics of early and multi-period formations. The study of combining the forming times and the history of hydrocarbon migration and accumulation is important for the research on forming of lithologic traps.

    Reef Trap Characteristics of Kais Carbonate in Salawati Basin, Indonesia
    YU Hui-long，XUE Liang-qing，YANG Fu-zhong, HONG Guo-liang
    2005, 19(3):  409-415. 
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    The Salawati Basin is located at the Bird's head of the Papua Island, Eastern Indonesia. The Miocene Kais carbonate in the Salawati Basin is one of the classic targets of the Tertiary in Southeast Asia. The reefs of the Kais Formation are the main producing reservoirs. By study on the basic petroleum geology, especially on the sedimentary characteristics and the Kais carbonate combined with recent new data from the PetroChina International Companies in Indonesia, the sedimentary characteristics of the lagoon facies in the Miocene are further studied, and the types of reefs and traps of the Kais Formation are systematically studied and divided. Four reef traps are classified, and the Kais carbonate can be divided into two parts in framework. There are permeable channels in the lower part of Kais carbonate, which contain steady reefal sediments and can act as migration paths of hydrocarbons. It is very important to recognize the characteristics of the reef traps correctly for further petroleum exploration in the basin。

    The Effect of Biodegradation on Alkylated Phenanthrene Distributions in Reservoired Oils
    HUANG Hai-ping，ZHOU Shu-qing，CHU Zhen-miao，GUO Ya-ting
    2005, 19(3):  416-424. 
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    Oil discovered from the Lengdong Oilfield, Liaohe Basin has similar source and maturity. Biodegradation is main cause leading to concentration and distribution variations of alkylated phenanthrenes. The concentrations and molecular distributions show systematic variations at different biodegradation levels.The concentration decreases significantly from level 3 to 5 while isomer distribution varies in slightly advanced biodegradation stage(＞level 4). Alkylated phenanthrene maturity parameters remain valid till biodegradation level 4. Degree of alkylation is a critical factor to control the rate of biodegradation.The C3-phenanthrenes show high ability to resist biodegradation compared to their low alkylated counterparts, however, we do observed methylphenanthrenes decrease faster than phenanthrene. Demethylation of a substituted compound during biodegradation was inferred as one of biodegradation reaction process. Alkylated isomer specific degradations are also observed in our sample set. Alkylphenanthrenes with substituents at the 9th or 10th position are more resistant to biodegradation than alkylphenanthrenes with substituents at other positions. The relative susceptibility to biodegradation for the individual methylphenanthrene(MP), C2-phenanthrene and C3-phenanthrene isomers were determined by their concentration variations.This result provides practical guide for aromatic hydrocarbon maturity parameter selection and further insight into mechanism and quantification of biodegradation in reservoired oils.

    The Mixing of Oils from Different Source Rocks：A Key Factor of Oil Enrichment of Daerqi Oilfield in Erlian Basin, Inner Mongolia
    JIN Guang-xing, XU Shu-tang, HOU Du-jie, TIAN Shi-cheng, HONG Ping
    2005, 19(3):  425-431. 
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    Based on physical features, gross compositions and biomarker compounds, the crude oils in Daerqi oilfield are classified into two types with distinct maturations: low mature and mature oil. Oil-source correlation shows that the oils are derived from low mature source rock of the Duhongmu Formation and mature source rock of the Aershan Formation respectively. The oil maturation index between low and mature may be the mixture of two source rocks. The inference can be proved by the artificial oil mixing test and oil-bearing sand serial extraction. By analyzing the characteristics of oil distribution and the relationship between hydrocarbon migration and fault developing history, it is concluded that the mixing of oils derived from different source rocks is a key control factor in oil enrichment.

    The Change of Oil-water Interface of Jurassic Reservoirs and History of Petroleum Accumulation in the Block Ⅰ，Center of Junggar Basin
    LI Wei, ZHANG Zhi-huan, LI Hai-ping, HAN Li-guo, Wang Qing
    2005, 19(3):  432-440. 
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    The present reservoir oil-water interface of each well in the Block Ⅰ, center of Junggar basin is predicted through analyzing the chemically extracted hydrocarbon residues and  Rock-eval data combining with comprehensive log interpretation.The frequency of mineral grains containing oil-bearing fluid inclusions (the GOI number) reflects the palaeo-oil saturation experienced in a sandstone reservoir irrespective of the present fluid phase. The location of the original oil-water interface of each well is defined through analyzing the detailed GOI mapping. It is concluded that the original oil-water contact is lower than the present contact；A detail study is undertaken to compare molecular parameters obtained from the analyses of core extracts and oil-bearing fluid inclusions. It is found that the molecular parameters of core extracts and oil-bearing fluid inclusions of well Zheng 1 are similar, while those of wells Sha 1 and Zhuang 1 are significantly different.Through the successful case study，it is predicted that the oils of well Zheng 1 are mainly derived from the source rocks of Changji sag in the south;  the oils of wells Sha 1 and Zhuang 1 are mixed oils, which are generated from the source rocks in the north and Changji sag.

    Remaining Oil Distribution and Its Potential Exploitation Measures in Block Zhuang 74 of Wuhaozhuang Oilfield, Shandong Province
    YUE Da-li, WU Sheng-he, LIN Cheng-yan, LI Yan
    2005, 19(3):  441-448. 
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    The development of extra-low permeability reservoir plays an important role in oil industry. Based on core and well logging data, the distal turbidite fan of Block Zhuang74 in Wuhaozhuang Oilfield can be divided into three subfacies, that is, root fan, middle fan and fan edge.In middle fan, five microfacies can be recognized such as braided channel, inter-channel, channel edge, front edge of middle fan and lobe.Internal, interlayer and plane heterogeneities are clarified, then the types and combined modes of micro-tectonics are summarized.On the basis of the analyses of dynamic and static data, the distribution and controlling factors of the remaining oil in extra-low permeability reservoir are revealed, including microfacies, reservoir heterogeneity, microtectonics and well network condition and so on.The enrichment regions of the remaining oil are predicted and potential exploitation measures are proposed, then the increments of remaining accessible reserves and the enhancement of recovery can be achieved.

    Microcosmic Dynamical Energies of Coalbed Gas Reservoir Formation of Qinshui Basin，Shanxi Province
    WU Cai-fang，QIN Yong，FU Xue-hai，ZENG Yong
    2005, 19(3):  449-457. 
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    The microcosmic dynamical energies of coalbed gas reservoir-forming action mostly showed in two aspects that one was the pore-fracture system, and the other was the hydrocarbon-generated action and the gas-storage action. Taking the coal reservoir in Qinshui Basin as a case, the paper went deep into anatomising the pore-fracture system and its developing evolution, the hydrocarbon-generated action and energy accumulation-emission, and clarified the controls of various microcosmic dynamical energies to coalbed gas reservoir formation. The researching results indicated that the tectonic action had obvious controls to coal reservoir permeability, and the energy accumulation of hydrocarbon-generated action was the important power to the cap-rock breaking action, and the energy emission mostly showed in the forming and developing of the pore-fracture system According to the aforementioned research, we could find the geological regionalization of coalbed gas reservoir formation in Qinshui Basin, which is shown that the advantaged area in the south of the Basin is Yangcheng and north Jincheng, including Panzhuang, Fanzhuang and Zhengzhuang; the advantaged area in the middle of the Basin is Anze-Qinyuan region which lies in the centre and south of the western slope of the Basin; in the north of the Basin, the likely advantaged area is the southeast Shouyang which lies in the middle of northeast Yuci and southwest Yangquan.

    New Method for Extraction of Contaminating Vegetation Using Multispectral Remote Sensing Data
    CHENG Bo， LIU Shao-feng， MEI Xue-feng
    2005, 19(3):  458-464. 
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    Environmental pollution is one of the most concerned issues in the 21st century. The effective monitoring to the present situation and change of the vegetation contamination is the predominance of the remote sensing technology. Based on the location and displacement pattern of vegetation on the vegetation plane constituted by red and near-infrared bands during the vegetation growth, this study established a mathematical model for rotating the coordinate system of the vegetation plane, and then introduced a new method for extracting the information of greenness that reflects the growth of the vegetation. Using the newly multispectral remote sensing data(ASTER), an investigation of the contamination of vegetation in Dexing Copper Mine,   Jiangxi Province, was launched to give a new example in distinguishing the environment situation by studying the growth and distribution of the vegetation in a flourish region. At the same time, the result could be also regarded as a valuable reference for other similar applications of the satellite data.

    Rock Mass and Concealed Rock Mass Information Extracted from Remotely Sensed Data in Yingzuishan Area, Gansu Province
    YANG Bo, LI Jing, CHEN Yun-hao，LAI Jian-qing, ZENG Xin-ping，TANG Pan-ke
    2005, 19(3):  465-470. 
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    This study selected Yingzuishan goldmine and its surrounding area in the east of Altun Mountain in Northwestern China as research area, and tried to find out a method that could automatically extract out the information of rock mass and concealed rock mass from Landsat-7 ETM+data in this area. The multi-level separation and extraction technique of remote sensing information was used, and we also statistically analyzed in-situ spectral data of ground objects and multivariate data from rock and mineral samples, and finally acquired several kinds of band combination types related to different rock mass alterations. On the basis of multi-band remote sensing data, we utilized the arithmetical operations, ratios and principal component analyses (PCA) etc, and obtained some variable images after information enhance treatment. Combining with the research on characteristic of the known rock mass, we found out the best variable image that included rock mass and concealed rock mass information at most, and extracted out the information from this image in the end. Field validation and comparative analysis between the results and the archived geological rock mass data both proved that this method has the advantage of high goodness of fit and satisfactory effect. Furthermore, the reasons for the error of the extracted information were also discussed.

    Research on the Sampling Technology of Environmental and Scientific Drilling
    HE Yuan-xin，XIA Bai-ru，ZHAO Er-xin
    2005, 19(3):  471-474. 
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    Environmental scientific drilling aims at providing in-situ sample for environmental scientific research. For this purpose, the shooting-type sampling technique with international advanced level, advanced hydraulic piston coring technique using the hydraulic pressure, and the environmental-protection drilling fluid were developed.Further fieldtests which were executed in Lop Nur and Turpan, Xinjiang, and Zhoukoudian, Beijing, indicated that shooting-type sampling technique could effectively reduce the vibration of drilling tool in the process of core drilling, thus could avoid autogenetic grinding of core and improve the reliability of core collection and obviously increase core recovery. It is also revealed that advanced hydraulic piston coring technique is suitable to soil formation with the characteristics of quick indentation, high recovery of soil core, in-situ structure of the core sample preserved and high representativeness, and that environmental-protection drilling fluid has excellent functions of low filtrate loss, strong rejection capability and good lubrication, thus effectively protect the stability of the hole wall and the intactness of the loose core without any environmental pollution.

    Influence of Water Permeation and Analysis of Treatment for the Longmen Grottoes
    YAN Shao-jun，FANG Yun, SUN Bing, GAO Hong
    2005, 19(3):  475-478. 
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    Based on the engineering geological and hydro-geological conditions of the Longmen Grottoes and the results of the environmental geological diseases survey of three test caves (Qianxisi Cave, Huangfugong Cave, Ludong Cave), the formation mechanism and the harmful effects of the penetrative water inside the caves are analyzed systematically in this paper. The harmful effects are divided into three categories: mechanical effect, chemical effect and biologic effect.The chemical effect is the most direct and apparent negative effect for the protection of the culture relics.It is presented that using two means, plugging and drainage, synthetically to treat water permeation in this paper. The methods are subdivided into four: outside plugging, inside plugging, draining the water from the internal rock mass and draining water from the earth's surface. A conclusion is drawn from the results of the investigation that it is not an appropriate treatment for the heavy penetration caves with one method—inside plugging. Cutting off the source and draining the water from the rock should be done firstly and plugging inside the caves should be adopted after the quantity of penetrative water is reduced adequately.

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