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The Sachakou Deposit in West Kunlun of Xinjiang: A Pb-Zn Polymetallic Deposit Associated with Magmatic Metasomatism of Carbonate Rock

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 883-884页

作者： ZHOU Menglin LIU Yingchao School of Earth Sciences and Resources China University of Geoscience (Beijing) Institute of Geology Chinese Academy of Geological Sciences (CAGS)

Objective The Sachakou Pb-Zn polymetallic deposit is located in Hetian County, Xinjiang （geographical coordinates of E78° 57＇ 54.30＂-78°59＇ 53.63＂, N34° 39＇ 27.50＂-34° 40＇ 57.21＂）. It belongs to the West Kunlun orogenic belt on the northwest edge of the Qinghai-Tibet Plateau and is connected to the Sanjiang orogenic belt to the south （Spurlin et al., 2005）. In recent years, a series of Pb-Zn mineralized spots and deposits have been discovered in this area one after another, which is called the Huoshaoyun ore concentration area. Among them, the Sachakou Pb-Zn deposit has reserves up to140 Mt, which has reached a large scale. However, the study on the genesis of deposits in this area has only just begun. This work studied the genesis ofthis Pb-Zn deposit in order to provide new ideas for the genesis of regional deposits and regional prospecting.

关键词： Pb A Pb-Zn Polymetallic Deposit Associated with Magmatic Metasomatism of Carbonate Rock The Sachakou Deposit in West Kunlun of Xinjiang Zn

Effects of water tables and nitrogen application on soil bacterial community diversity, network structure, and function in an alpine wetland, China

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Journal of Arid Land 2024年第11期16卷 1584-1603页

作者： HAN Yaoguang CHEN Kangyi SHEN Zhibo LI Keyi CHEN Mo HU Yang WANG Jiali JIA Hongtao ZHU Xinping YANG Zailei College of Grassland Science Xinjiang Agricultural UniversityUrumqi 830052China College of Resources and Environment Xinjiang Agricultural UniversityUrumqi 830052China College of Bioscience and Resources Environment Beijing University of AgricultureBeijing 102206China Xinjiang Key Laboratory of Soil and Plant Ecological Processes Urumqi 830052China The Second geological brigade Hebei Bureau of Geology and Mineral Exploration and DevelopmentTangshan 063000China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory for North China Urban Agriculture of Ministry of Agriculture and Rural Affairs Beijing 102206China

Nitrogen deposition and water tables are important factors to control soil microbial community ***,the specific effects and mechanisms of nitrogen deposition and water tables coupling on bacterial diversity,abundance,and community structure in arid alpine wetlands remain *** nitrogen deposition(0,10,and 20 kg N/(hm^(2)•a))experiments were conducted in the Bayinbulak alpine wetland with different water tables(perennial flooding,seasonal waterlogging,and perennial drying).The 16S rRNA(ribosomal ribonucleic acid)gene sequencing technology was employed to analyze the changes in bacterial community diversity,network structure,and function in the *** indicated that bacterial diversity was the highest under seasonal waterlogging ***,nitrogen deposition only affected the bacterial Chao1 and beta diversity indices under seasonal waterlogging *** abundance of bacterial communities under different water tables showed significant differences at the phylum and genus *** dominant phylum,Proteobacteria,was sensitive to soil moisture and its abundance decreased with decreasing water *** nitrogen deposition led to changes in bacterial abundance,such changes were small compared with the effects of water *** deposition with 10 kg N/(hm^(2)•a)decreased bacterial edge number,average path length,and ***,perennial flooding and drying conditions could simply resist environmental changes caused by 20 kg N/(hm^(2)•a)nitrogen deposition and their network structure remain *** sulfur cycle function was dominant under perennial flooding condition,and carbon and nitrogen cycle functions were dominant under seasonal waterlogging and perennial drying *** application increased the potential function of part of nitrogen cycle and decreased the potential function of sulfur cycle in bacterial *** summary,composition of bacterial community in the arid alpine wetland was

关键词： nitrogen application alpine wetland bacterial community bacterial network water tables

geological IMPLICATION OF GEOPHYSICAL DATA IN THE HOLOCENE SUBAQUEOUS DELTA OF THE CHANGJIANG RIVER

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Acta Oceanologica Sinica 1987年第S2期 231-242页

作者：黄慧珍沈邦培胡强生 Comprehensive Research brigade of Marine Geology Ministry of Geology ami Mineral Resources Shanghai

3000 km sounding and shallow seismic profiles have been obtained in the investigation of the Holocene subaqueous Changjiang River Delta by the Bureau of Marine geological Survey. The survey area is about 40 000km2 outside the Changjiang River mouth (from the coast in the west to 124°E in the east, between 30°10’ and 32°N).Based on the explanation of these shallow seismic profiles and the stratigraphical data from boreholes the average interval velocities of the seismic wave have been estimated, the geological ages of the layer sets and interfaces in the shallow seismic profiles have been defined. From these analyses the boundary of the Holocene subaqueous Changjiang River Delta, the thickness variation and regional distribution pattern of the Holocene strata in this delta can be *** analyses also provide important information on the sedimentary environments, sea level fluctuation, and different sedimentary facies of same age. These results provide data for mapping of isopach of Holocene

关键词： area geological IMPLICATION OF GEOPHYSICAL DATA IN THE HOLOCENE SUBAQUEOUS DELTA OF THE CHANGJIANG RIVER

Optimizing data for electrical resistivity tomography in hardened sites through the ratio method

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Journal of Southeast University(English Edition) 2024年第4期40卷 372-385页

作者： Jiang Fuyu Gao Likun Chen Haijun Ni Jiong Li Fuqiang School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China The First geological brigade of Jiangsu Geology and Mineral Resources Bureau Nanjing 210041China Nanjing Hydraulic Research Institute Nanjing 210029China China Energy Engineering Group Hunan Electric Power Design Institute Co. Ltd.Changsha 410007China

To reduce the shielding effect of hardened layers on electrical resistivity tomography,a ratio method based on the distortion correction principle and the isolation coefficient is *** effects of the resistivity and thickness of hardened concrete layers on the detection of target objects are *** numerical simulations and indoor tank tests indicate that when the ratio method is employed to correct the original collected data,the maximum allowable error for the isolation coefficient should not exceed 1%.Notably,when the ratio of hardened layer thickness to electrode spacing does not exceed 1,correction through this method significantly enhances the recognition capability of target ***,when the hardened layer thickness is greater than the electrode spacing by a factor of 2 or more,the ratio method cannot achieve satisfactory *** case study of flood control engineering detection in the Zhangxi section of the Huangpen River in Dongzhi County demonstrates that the detection effect after correction by the ratio method is comparable to that for the adjacent unhardened pavement,and the influence of the hardened layer is obviously weakened,resulting in more reliable results.

关键词： ratio method resistivity tomography hardened site distortion principle data optimization

A COMPREHENSIVE STUDY ON LITHOSPHERIC STRUCTURE IN NORTH CHINA

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Chinese Science Bulletin 1988年第21期33卷 1803-1807页

作者：冯锐郑书真 Institute of Geophysics State Seismological Bureau Beijing Geophysical Exploration brigade State Seismological Burcau Zhengzhou

In the last three years a vast amount of new geological and geophysical data have been collected and processed in our study. Then a strict three-dimensional gravitational computation combined with seismic data has bee... 详细信息

关键词： lithospheric structure gravitational inversion North China

Automatic Identification of Cracks from Borehole Image Under Complicated geological Conditions

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Journal of Shanghai Jiaotong university(Science) 2013年第6期18卷 699-705页

作者：冯少孔黄涛李宏阶 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research and Hydropower Research School of Naval Architecture Ocean and Civil Engineering China Institute of Water Resources and Hydropower Research No.125 Geology brigade Hubei Bureau of Coal Geology

Identifying cracks from the spread image of a borehole wall is one of the most common usages of borehole imaging method. The manual identification of cracks is time-consuming and can be easily influenced by objective judgment. In this study, firstly, the image translation from RGB color model to HSV color model is done to highlight the structural plane region, which is closer to the color recognition of human sight; secondly, the Saturation component is filtered for further processing and a twice segmentation method is proposed to improve the accuracy of automatic identification. The primary segmentation is based on the statistics of saturation over a longer borehole section and can give a rough estimation of a crack. Then, the pixels are shifted in the reverse direction to the sine curve estimated and make the centerline of the crack flat. Based on the shifted image, the secondary segmentation is done with a small rectangle region that takes the baseline of the roughly estimated crack as its centerline. The result of the secondary segmentation can give a correction to the first estimation. Through verifying this method with actual borehole image data, the result has shown that this method can identify cracks automatically under very complicated geological conditions.

关键词： borehole image crack recognition image processing segmentation Hough transform HSV color model

Hydrogeological Hazards and Control Measures in Engineering geological Exploration

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Journal of geological Research 2019年第1期1卷 46-49页

作者： Pengna Zhou No.801 Hydrogeological Engineering Geology brigade of Shandong Bureau of Geology and Mineral Resources (Institute of Geology and Mineral Resources of Shandong Province). Jinan Shandong250000China

For engineering geological investigation, hydrographic surveys are particularly important. By operating the equipment, relevant technicians analyze hydrogeological data around the project. A series of corresponding measures were taken to ensure the smooth completion of the project. However, due to the inadequate completion of hydrogeological survey work, it has great harm to the later stage of engineering work, and even will lead to the final failure of the project. Based on this, this paper explores the hazards and prevention measures of hydrogeology in engineering surveys.

关键词： Engineering investigation Hydrogeology Problems Hazards Prevention and control measures

Geology and Genesis of the Superlarge Jinchang Gold Deposit,NE China

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Acta Geologica Sinica(English Edition) 2008年第4期82卷 750-761页

作者： JIA Guozhi CHEN Jinrong YANG Zhaoguang BIAN Hongye WANG Yangzhong LIANG Haijun JIN Tonghe LI Zhenhui No. 1 brigade Division of Gold People＇s Armed Police Force Harbin Heilongjiang 150086 Institute of Gold Geology Division of Gold People＇s Armed Police Force Langfang Hebei 065000 No. 1 Team Division of Gold People＇s Armed Police Force Mudanjiang Heilongjiang 157000 No. 3 Team Division of Gold People＇s Armed Police Force Harbin Heilongjiang 150049

The superlarge Jinchang gold deposit is located in the joint area between the Taipingling uplift and the Laoheishan depression of the Xingkai Block in both eastern Jilin and eastern Heilongjiang Province. Wall rocks of the gold deposits are the Neoproterozoic Huangsong Group of metamorphic rocks. Yanshanian magmatism in this region can be divided into 5 phases, the diorite, the graphic granite, the granite, the granite porphyry and the diorite porphyrite, which resulted in the magmatic domes and cryptoexplosive breecia chimney followed by large-scale hydrothermal alteration. Gold mineralization is closely related to the fourth and fifth phase of magmatism. According to the occurrences, gold ores can be subdivided into auriferous pyritized quartz vein, auriferous quartz-pyrite vein, auriferous polymetailic sulfide quartz vein and auriferous pyritized calcite vein. The ages of the gold deposit are ranging from 122.53 to 119.40 Ma. The ore bodies were controlled by a uniform tectono-magmatic hydrothermal alteration system that the ore-forming materials were deep derived from and the ore-forming fluids were dominated by magmatic waters with addition of some atmospheric water in the later phase of mineralization. Gold mineralization took place in an environment of medium to high temperatures and medium pressures. Ore-forming fluids were the K^＋-Na^＋-Ca^2＋-Cl^--SO4^2- type and characterized by medium salinity or a slightly higher, weak alkaline and weak reductive. Au in the ore-forming fluids was transported as complexes of [Au （HS）2]^-, [AuCl2]^-, [Au（CO2）]^- and [Au（HCO3）2]^-. Along with the decline of temperatures and pressures, the ore-forming fluids varied from acidic to weak acidic and then to weak alkaline, which resulted in the dissociation of the complex and finally the precipitation of the gold.

关键词： magmatic dome cryptoexplosive breccia pipe ring and radial faults gold deposit,superlarge Jinchang Taipingling Heilongjiang

Development and application of turbodrills in hot dry rock drilling

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Journal of Groundwater Science and Engineering 2018年第1期6卷 1-6页

作者： ZHANG De-long WENG Wei ZHAO Chang-liang XU Jun-jun YANG Peng HUANG Yu-wen HU Zhen-zhong Beijing Institute of Exploration Engineering No.29 Xueyuan RoadHaidian DistrictBeijing 100083China The Second Hydro-geology&Geo-engineering brigade of Shandong Provincial Bureau of Geology and Mineral DezhouShandong Province 253015China. SINOPEC Henan Oilfield Branch Company Henan Nanyang OilfieldNanyang CityHenan Province 473132China

The strata of hot dry rock(HDR) are usually igneous rocks with high temperature which are challenging for drilling activities. This paper deals with the key technology and research of turbodrills, introduced the application of turbodrills in HDR drilling at home and broad, and analyzed the field application cases. With the advancement such as low speed high torque turbodrill, reduction turbodrills, independent spindlesection and PDC bearings and so on, the application of turbodrills has widely expanded. The application of high-temperature turbodrills in Fenton Hill, HDR geothermal wells, high-temperature formation in Tahe oilfield all proved that turbodrills are the best downhole motors in deep high-temperature HDR drilling, thus they deserve further research and generalization.

关键词： Hot dry rock HDR drilling Geothermal drilling Turbodrill Field application