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华北克拉通东北缘改造:来自吉林辉南地区构造热事件的古地磁记录

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地质通报 2024年第2期43卷 289-301页

作者：金继浩任收麦王胜建刘永江侯啓东刘一珉王浩中国石化胜利油田分公司孤东采油厂山东东营257237 中国地质调查局北京100037 中国地质调查局油气资源调查中心北京100083 中国海洋大学海洋地球科学学院山东青岛266100 中国地质大学(北京)地球科学与资源学院北京100083 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029

华北克拉通东北缘处于构造运动活跃地区,古地磁研究可为构造演化和岩浆热事件提供依据。笔者在吉林辉南地区中寒武统32个采点共采集246块样品进行了岩石学、岩石磁学及系统热退磁实验。古地磁实验表明,徐庄组砂质泥岩主要磁性矿物是赤... 详细信息

华北克拉通东北缘处于构造运动活跃地区,古地磁研究可为构造演化和岩浆热事件提供依据。笔者在吉林辉南地区中寒武统32个采点共采集246块样品进行了岩石学、岩石磁学及系统热退磁实验。古地磁实验表明,徐庄组砂质泥岩主要磁性矿物是赤铁矿和磁铁矿,张夏组灰岩主要磁性矿物是颗粒较小的磁铁矿和黄铁矿,且均发生了重磁化,并记录了稳定的中温分量,前者中温分量地理坐标平均方向为D/I=10.9°/50.8°,α_(95)=11.7°,对应的极位置为76°N,264.6°E,A_(95)=13°,与早白垩世岩浆活动记录的古地磁极位置一致;后者中温分量地理坐标平均方向为D/I=29.1°/59.0°,α_(95)=6.5°,对应的极位置为68°N,213.7°E,A_(95)=8.4°,与第四纪火山岩记录的古地磁极位置一致。综合区域地质背景分析,早白垩世—第四纪,吉林辉南及邻区古地磁记录的2次较为强烈的构造热事件,以及因敦化-密山断裂带左旋走滑运动造成的北向运移形成的古纬度差,一定程度上对华北克拉通东北缘起到双重改造作用。

关键词：华北克拉通东北缘中寒武世重磁化构造热事件

Mineralogy and Chemistry of Sulfides from the longqi and Duanqiao Hydrothermal Fields in the Southwest Indian Ridge

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1798-1822页

作者： ZHANG Baisong lI Zhenqing hou Zengqian ZHANG Weiyan XU Bo China University of Geosciences Beijing 100083 institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 institute of geology Chinese Academy of Geological Sciences Beijing 100037 Second institute of Oceanography State Oceanic Administration Hangzhou 310012

Recent investigations found that hydrothermal activity and sulfide mineralization occurs along the Southwest Indian Ridge（SWIR）. The longqi and Duanqiao hydrothermal fields between 49° E and 53° E of the SWIR are two prospective mineralization areas discovered by chinese scientists. With the aim to determine the mineralogical and chemical characteristics of sulfide minerals, we have conducted detailed studies for samples from the two areas using an optical microscope, X-ray diffractometer, scanning electron microscope, and electron microprobe. The mineralization processes in the longqi area are divided into three main stages：（1） the low-medium-temperature stage： colloform pyrite（Py I）＋ marcasite → euhedral pyrite（Py II）,（2） the high-temperature stage： isocubanite（±exsolved chalcopyrite）＋ pyrrhotite → coarse-grained chalcopyrite（Ccp I）, and（3） the medium–low-temperature stage： sphalerite ＋ fine-grained chalcopyrite inclusions（Ccp II） → aggregates of anhedral pyrite（Py III） ± marcasite → Fe-oxide（-hydroxide）＋ amorphous silica. The mineralization processes in the Duanqiao area are divided into two main stages：（1） the medium–high-temperature stage： subhedral and euhedral pyrite（Py I′） → coarse-grained chalcopyrite（Ccp I′） and（2） the medium–low-temperature stage： sphalerite → fine-grained chalcopyrite（Ccp II′）＋ chalcopyrite inclusions（Ccp II′） → silica-cemented pyrite（Py II′）＋ marcasite → Fe-oxide ＋ amorphous silica. We suggest that the fine-grained chalcopyrite inclusions in sphalerite from longqi and Duanqiao were formed by co-precipitation and replacement mechanisms, respectively. Primary sphalerites from both fields are enriched in Fe（avg. 5.84 wt% for the longqi field vs. avg. 3.69 wt% for the Duanqiao field）, Co（avg. 185.56 ppm for the longqi field vs. 160.53 ppm for the Duanqiao field）, and Cd（avg. 1950 ppm for the longqi field vs. avg. 525.26 ppm for the Duanqiao field）. Cu contents in pyrite from the Duanqiao field（Py I′： avg. 849.23 ppm and Py II′： avg. 11

关键词： mineralogy mineralogical chemistry longqi Duanqiao Southwest Indian Ridge(SWIR)

The Zhaxikang Vein-type Pb-Zn-Ag-Sb Deposit in Himalayan Orogen, Tibet： Product by Overprinting and Remobilization Processes during Post-collisional Period

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 682-705页

作者： lIANG Wei hou Zengqian ZHENG Yuanchuan YANG Zhusen lI Zhenqing Chengdu Center China Geological Survey Chengdu 610082 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China China university of geosciences Beijing 100037 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 10003 7 China

The Zhaxikang Pb-Zn-Ag-Sb deposit, the largest polymetallic deposit known in the Himalayan Orogen of southern Tibet, is characterized by vein-type mineralization that hosts multiple mineral assemblages and complicated metal associations. The deposit consists of at least six steeply dipping vein- type orebodies that are hosted by Early Jurassic black carbonaceous slates and are controlled by a Cenozoic N-S-striking normal fault system. This deposit records multiple stages of mineralization that include an early period （A） of massive coarse-grained galena-sphalerite deposition and a later period （B） of Sb-bearing vein-type mineralization. Period A is only associated with galena-sphalerite mineralization, whereas period B can be subdivided into ferrous rhodochrosite-sphalerite-pyrite, quartz -sulfosalt-sphalerite, calcite-pyrite, quartz-stibnite, and quartz-only stages of mineralization. The formation of brecciated galena and sphalerite ores during period A implies reworking of pre-existing Pb -Zn sulfides by Cenozoic tectonic deformation, whereas period B mineralization records extensive open- space filling during ore formation. Fluid inclusion microthermometric data indicate that both periods A and B were associated with low-medium temperature （187-267℃） and low salinity （4.00-10.18% wt. NaCl equivalent） ore-forming fluids, although variations in the physical-chemical nature of the period B fluids suggest that this phase of mineralization was characterized by variable water/rock ratios. Microprobe analyses indicate that Fe concentrations in sphalerite decrease from period A to period B, and can be divided into three groups with FeS concentrations of 8.999-9.577, 7.125-9.109, 5.438-1.460 mol.%. The concentrations of Zn, Sb, Pb, and Ag within orebodies in the study area are normally distributed in both lateral and vertical directions, and Pb, Sb, and/or Ag concentrations are positive correlation within the central part of these orebodies, but negatively correlate in th

关键词： polymetallic multiple period and stage mineralization overprinting and remobilization,orogenic belt Zhaxikang Tibet

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隧道工程勘察中的超前预报成像方法研究

地球物理学报 2018年第3期61卷 1150-1156页

作者：查欣洁高星王伟侯献华杨飞张小艳资源与环境信息系统国家重点实验室中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049 国土资源部盐湖资源与环境重点实验室中国地质科学院矿产资源研究所北京100037

针对地下工程领域隧道超前预报地震波波场传播与成像中存在的问题,通过数值模拟,构建二维含低速异常的隧道介质模型,研究隧道弹性波场传播规律和异常体边界成像准确性.首先,利用一阶速度-应力波动方程和高阶交错网格有限差分计算方法,... 详细信息

针对地下工程领域隧道超前预报地震波波场传播与成像中存在的问题,通过数值模拟,构建二维含低速异常的隧道介质模型,研究隧道弹性波场传播规律和异常体边界成像准确性.首先,利用一阶速度-应力波动方程和高阶交错网格有限差分计算方法,导出隧道超前预报数值模拟的稳定性条件和边界条件,对上述隧道模型进行数值模拟,识别波场特征;其次,利用叠前逆时偏移成像方法,对压制噪音干扰后的波场在互相关成像条件下,对隧道模型中的异常体边界进行逆时偏移成像.研究结果表明:采用高阶交错网格有限差分正演获得异常体边界清晰的反射波和角点产生的散射波;逆时偏移算法获得隧道内异常体准确成像结果,从而大大提高隧道超前预报的分辨率与准确性;靠近掌子面单一震源、多道接收观测系统对异常体成像效果最佳,为隧道内高效数据采集提供理论依据.

关键词：超前预报交错网格逆时偏移

Observations and modeling of flat subduction and its geological effects

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Science China Earth sciences 2020年第8期63卷 1069-1091页

作者： Zhiyong YAN lin CHEN Xiong XIONG Kai WANG Renxian XIE hou Tze HSU MOE Key laboratory of Fundamental Physical Quantities Measurement&Hubei Key laboratory of Gravitation and Quantum Physics PGMF and School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China institute of Geophysics and PGMF Huazhong University of Science and TechnologyWuhan 430074China State Key laboratory of Geodesy and Earth s Dynamic Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhan 430077China State Key laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

Flat subduction refers to low-angle(<10°) or sub-horizontal subduction of oceanic slabs. Flat subduction is only recognized in ~10% of present-day subduction zones, but its impact on the behavior of the overriding pl... 详细信息

Flat subduction refers to low-angle(l subduction of oceanic slabs. Flat subduction is only recognized in ~10% of present-day subduction zones, but its impact on the behavior of the overriding plate is particularly *** example, flat subduction zones are typically associated with stronger earthquakes. The deformation caused by typical flat subduction will transfer from the trench to the overriding continental interior and form a broad magma belt. The formation mechanism of flat subduction has been linked to the relative buoyancy of subducted oceanic plateaus, overthrusting of the overriding plate, hydrodynamic suction, and trench retreat. However, these mechanisms remain debated. This paper systematically analyzes and summarizes previous studies on flat subduction, and outlines the possible geological effects of flat subduction, such as intracontinental orogeny and magmatism. Using examples from numerical modeling, we discuss the possible formation mechanisms. The most important factors that control the formation of flat subduction are associated with overthrusting of the overriding plate and the arrival of an oceanic plateau at the subduction zone. In addition, trench retreat is necessary to enable flat subduction. Hydrodynamic suction contributes to the reduction of the slab dip angle, but is insufficient to form flat subduction. Future numerical modeling of flat subduction should carry out three-dimensional high-resolution thermo-mechanical simulation, considering the influence of crustal eclogitization(negative buoyancy) and mantle serpentinization(positive buoyancy) of oceanic lithosphere, in combination with geological and geophysical data.

关键词： Flat subduction Magmatism Intracontinental orogeny Formation mechanism Numerical modeling

Geoscience knowledge graph in the big data era

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Science China Earth sciences 2021年第7期64卷 1105-1114页

作者： Chenghu Zhou Hua WANG Chengshan WANG Zengqian hou Zhiming ZHENG Shuzhong SHEN Qiuming CHENG Zhiqiang FENG Xinbing WANG Hairong lV Junxuan FAN Xiumian HU Mingcai hou Yunqiang ZHU State Key laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100049China School of Earth sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China institute of Artificial Intelligence Beihang UniversityBeijing 100191China State Key laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China Sinopec Petroleum Exploration&Production Research institute Beijing 100083China School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Automation Tsinghua UniversityBeijing 100084China institute of Sedimentary geology Chengdu University of TechnologyChengdu 610059China

Since the beginning of the 21 st century,the geoscience research has been entering a significant transitional period with the establishment of a new knowledge system as the core and with the drive of big data as the *** is a revolutionary leap in the research of geoscience knowledge discovery from the traditional encyclopedic discipline knowledge system to the computer-understandable and operable knowledge *** on adopting the graph pattern of general knowledge representation,the geoscience knowledge graph expands the unique spatiotemporal features to the Geoscience knowledge,and integrates geoscience knowledge elements,such as map,text,and number,to establish an all-domain geoscience knowledge representation model.A federated,crowd intelligence-based collaborative method of constructing the geoscience knowledge graph is developed here,which realizes the construction of high-quality professional knowledge graph in collaboration with global *** also develop a method for constructing a dynamic knowledge graph of multi-modal geoscience data based on in-depth text analysis,which extracts geoscience knowledge from massive geoscience literature to construct the latest and most complete dynamic geoscience knowledge graph.A comprehensive and systematic geoscience knowledge graph can not only deepen the existing geoscience big data analysis,but also advance the construction of the high-precision geological time scale driven by big data,the compilation of intelligent maps driven by rules and data,and the geoscience knowledge evolution and reasoning analysis,among *** will further expand the new directions of geoscience research driven by both data and knowledge,break new ground where geoscience,information science,and data science converge,realize the original innovation of the geoscience research and achieve major theoretical breakthroughs in the spatiotemporal big data research.

关键词： Geoscience knowledge graph All-domain geoscience knowledge representation model Federated crowd intelligence collaboration High-precision geological time scale

Combating climate change in a post-COVID-19 era

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Science Bulletin 2020年第23期65卷 1958-1960页

作者： Nianzhi Jiao Fahu Chen Zengqian hou State Key laboratory of Marine Environmental Science and College of Ocean and Earth sciences Xiamen UniversityXiamen 361005China Joint lab for Ocean Research and Education(lORE)at Dalhousie University HalifaxNS B3H 4R2Canada Shandong University Ji'nan 266200China Key laboratory of Alpine Ecology Center for Excellence in Tibetan Plateau Earth Sciences and Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China institute of geology Chinese Academy of Geological SciencesBeijing 100037China National Natural Science Foundation of China Beijing 100085China

An unprecedented global crisis of COVID-19 pandemic evokes the world’s thinking about the future of humankind. This pandemic is no doubt one of the major disasters in human history, comparable to the medieval Black Death(bubonic plague), and the 1918 influenza. It is even called the ‘‘Third World War" because of the profound impacts on the political, economic and global *** as historical event。

关键词： doubt profound thinking

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多场耦合的冲击地压防治研究

Applied Geophysics 2024年第1期21卷 119-132,205页

作者：刘伟建侯梦杰董森森肖扬邓志刚王浩楠张志增中原工学院建筑工程学院郑州451100 郑州安岩智能科技有限公司郑州450000 煤炭科学技术研究院有限公司北京100013

研究煤岩体中断层、采空区、陷落柱等异常地质体的活化规律,对煤矿开采过程中可能发生的冲击地压、煤与瓦斯突出、突水等地质灾害进行及时预警,对回采过程中长壁工作面斜交正断层围岩应力场和位移场演变特征进行数值模拟,同时采用高精... 详细信息

研究煤岩体中断层、采空区、陷落柱等异常地质体的活化规律,对煤矿开采过程中可能发生的冲击地压、煤与瓦斯突出、突水等地质灾害进行及时预警,对回采过程中长壁工作面斜交正断层围岩应力场和位移场演变特征进行数值模拟,同时采用高精度微地震监测系统对其活化孕灾过程进行监测,将数值模拟结果和微震监测结果进行耦合分析。结果表明:断层和采空区附近的煤岩体属于高应力区,发生微震事件频次高,能量大,工作面推采至断层处顶板的位移变化更加显著。本文采用微地震监测和数值模拟耦合分析方法,能够有效地揭示煤岩中异常地质体活化过程,对冲击地压灾害进行预警,该方法为具有相同类型地质特点的工作面安全回采提供了参考。

关键词：微地震监测数值模拟断层耦合分析

Preliminary Study on Raw Materials Exploitation at Donggutuo Site,Nihewan Basin,North China

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人类学学报 2002年第S1期21卷 53-66页

作者： PEI Shu-wen hou Ya-mei institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SiciencesBeijing 100044China

The present study examines material quarrying, utilization, and exploitation strategy with respect to availability, quality and distribution at Donggutuo, a lower Pleistocene archeological site in the Nihewan Basin of North China. Through identification of the bedrocks in the vicinity, the analysis reveals that raw materials available at the Donggutuo site are mainly chert, dolomicrite, siliceous dolomite, siliceous limestone, tectonic breccia, quartzite and intermediate lava. Related documents and a geological survey of the area demonstrate that the chert was quarried from dolomite within the Gaoyuzhuang Formation of the Mesoproterozoic Changcheng Group, and the quartzite from the Yousuopu Formation of the Archeozoic Qianxi Group, as well as from Jurassic volcanic lava. Fractures formed by tectonic movements of the Yanshan Stage and the Himalaya Stage made it convenient to quarry these materials. It is observed that fragmentary rock pieces were directly collected and quarried from local fracture belts and that this became the principal strategy of raw material exploitation adopted by the Donggutuo toolmakers. In general, raw materials were not efficiently used, and many of them could have been reduced, retouched and used again. Some suggestions are also proposed to improve the understanding of earlyhumans’ tool complex in the Nihewan Basin.

关键词： Raw materials Donggutuo lower Pleistocene