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Age Assignment of the Lycoptera- bearing Bed

Acta Geologica Sinica(English Edition) 1994年第3期68卷 329-347页

作者： li peixian, su deying, li yougui and yu jingxianinstitute of geology, Chinese Academy of Geological Sciences,{3. Chinese Academy of Geological Sciences Beijing

In the Yanliao area, the occurrence of the Nestoria-Keratestheria fauna and the Eoparacypris- Luanpingella-Darwinula assemblage in the Dabeigou Formation s.s., a Rb-Sr isochron age of 145.2 Ma for the Baiqi Formation and a complete stratigraphic sequence-all this proves that the Lycoptera-bearing bed overlies the Upper Jurassic. The Jehol fauna comprises the primitive Trigonioidids fauna, Eosestheria fauna, Lycoptera fauna et al., and their own laws of evolution expound that they belong to Cretaceous faunas. The associations of Eosestheria with Yanjiestheria, Lycoptera with Eosestheria, and Kuntulunia with Yanjiestheria as well as the occurrence of early angiosperms and sporo - pollen in the Fuxin Formation and its equivalents also demonstrate that the Lycoptera-bearing, bed should be assigned to the Cretaceous. The confirmation of the existence of Aucellina in the Jixi Group and the correlation of Trigonioidids and Cypridids with those in the equivalent strata of Japan and Western Europe have also been verified by corresponding marine strata. According to the magnetostratigraphic data from Zhejiang and Songliao, it has been preliminarily ascertained that M0 between the mixed polarity zone in the lower part and the normal polarity zone in the middle part of the Cretaceous is located in the upper member of the Huangjian Formation of the Jiande Group and the top member of the Denglouku Formation of the same group, and the isotopic age data of the Jehol and Jiande Groups show that the approximate geologic age of the Lycoptera bed is 13.-122 Ma. These prove that the Lycoptera bed should be assigned to the Cretaceous.

关键词： Cretaceous Jurassic-Cretaceous boundary Lycoptera- bearing bed Jehol fauna

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荒漠化矿区土壤碳排放高光谱遥感反演

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光谱学与光谱分析 2024年第10期44卷 2840-2849页

作者：刘英刘宇岳辉毕银丽彭苏萍贾羽豪西安科技大学测绘科学与技术学院陕西西安710054 西安科技大学西部矿山生态环境修复研究院陕西西安710054 西安科技大学地质与环境学院陕西西安710054 中国矿业大学(北京)地球科学与测绘工程学院北京100083

随着我国“碳达峰、碳中和”政策的提出,矿区碳排放成为关注焦点,然而目前缺少矿区土壤碳排放高光谱遥感探测的有效方法。基于矿区实测土壤样品,将6种光谱数学变换方法(R、■、Log(1/R)、1st、MSC、SNV)与光谱特征筛选方法(CC-SPA)相结... 详细信息

随着我国“碳达峰、碳中和”政策的提出,矿区碳排放成为关注焦点,然而目前缺少矿区土壤碳排放高光谱遥感探测的有效方法。基于矿区实测土壤样品,将6种光谱数学变换方法(R、■、Log(1/R)、1st、MSC、SNV)与光谱特征筛选方法(CC-SPA)相结合,探究新疆红沙泉露天煤矿不同土地利用类型土壤碳排放的高光谱响应特征;结合土壤温度(ST)、土壤湿度(SM)及6种光谱指数(NDVI、RVI、NGli、SMMI、SI-T、ATI),利用偏最小二乘(PLSR)、支持向量机(SVM)、随机森林(RF)、遗传优化神经网络(GA-BP)算法得到土壤碳排放最优遥感反演模型。主要结论如下:(1)自然条件下非采矿影响区土壤反射率明显高于采矿影响区,其中南线受煤炭开采影响最大,反射率最低,证明采矿活动对矿区土壤产生了影响;(2)光谱特征筛选方面,基于相关系数-连续投影算法(CC-SPA)提取的碳排放特征波段数远小于单一方法,且筛选结果呈现聚集式分布,主要集中于1600~2200 nm波长范围内,白天特征波段数远高于夜晚,相较于白天,夜晚特征波段具有明显向长波移动的特征。(3.添加基于反射率构建的光谱指数及ST、SM的反演模型估测土壤碳排放速率的精度明显提升,基于一阶微分变换(1st)的支持向量机模型(SVM)模型反演矿区综合土地利用类型土壤碳排放效果最好(验证集R2=0.813.RMSE=0.116);5种不同土地利用类型土壤碳排放最佳指数组合方式存在差异,引入不同的光谱指数对土壤碳排放速率的估测精度均有不同程度的提升(验证集R2均在0.8以上),其土壤碳排放最优反演模型均可较为准确地估算红沙泉矿区不同土地利用类型土壤的碳排放速率。本研究可为荒漠化矿区土壤碳排放遥感反演提供依据,定量识别不同土地利用类型下土壤的碳源汇效应,并实现了矿区碳排放的无损探测,为我国“3.·60”双碳目标提供数据支撑。

关键词：碳排放高光谱不同土地利用类型昼夜荒漠化矿区

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准噶尔盆地吉木萨尔凹陷页岩水平井水力压裂裂缝形态

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新疆石油地质 2024年第1期45卷 72-80页

作者：方正陈勉王溯李嘉成吕嘉昕余延波焦冀博中国石油大学(北京)石油工程学院北京102249 中国石油新疆油田公司工程技术研究院(监理公司) 新疆克拉玛依834000 中国石油西部钻探井下作业公司(储层改造研究中心) 新疆克拉玛依834000 中国石油西部钻探地质研究院(录井工程分公司) 新疆克拉玛依834000

准噶尔盆地吉木萨尔凹陷、四川盆地南部等地区页岩水平井的微地震侧视数据云图中均出现了平行于层理方向数据点的密度与扩展程度都远远大于垂直方向的现象,与传统的水力压裂裂缝几何形态解释结果矛盾,但是目前没有明确的三维水力压裂裂... 详细信息

准噶尔盆地吉木萨尔凹陷、四川盆地南部等地区页岩水平井的微地震侧视数据云图中均出现了平行于层理方向数据点的密度与扩展程度都远远大于垂直方向的现象,与传统的水力压裂裂缝几何形态解释结果矛盾,但是目前没有明确的三维水力压裂裂缝几何形态对这种现象做出解释。建立微地震数据反演方法,并对反演结果进行了二次重构,给出了页岩水平井三维水力压裂裂缝几何形态,并通过真三轴压裂物理模拟实验对裂缝形态以及微地震数据反演方法进行了验证。研究结果表明:反演得到的裂缝在三维空间中主要呈现出1条主裂缝与多条次生裂缝相互交错的形态,结合真三轴压裂物理模拟实验结果,说明了页岩水平井水力压裂裂缝几何形态呈水平垂直交错;通过对比声发射实验结果和吉木萨尔凹陷露头样品真三轴压裂物理模拟后呈现出的裂缝形态,验证了微地震数据反演方法的可靠性以及页岩水平井水力压裂裂缝的复杂性。

关键词：准噶尔盆地吉木萨尔凹陷页岩水平井储集层微地震水力压裂裂缝形态

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The impacts of base level and lithology on fluvial geomorphic evolution at the tectonically active Laohu and Hasi Mountains,northeastern Tibetan Plateau

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Science China Earth Sciences 2021年第6期64卷 906-919页

作者： Zhengchen li Xianyan WANG Yang yu Huiping ZHANG Qi su Xiaodong MIAO Huayu LU School of Geography and Ocean Science Nanjing UniversityNanjing210023China Institute of geology China Earthquake AdministrationBeijing100029China School of Resource and Environmental Sciences Linyi UniversityLinyi276000China

Previous researches had emphasized tectonic impacts on the fluvial system at the tectonically active areas,while the effects of lithology and local base level change have received relatively rare *** we investigated fluvial landforms at different spatial scales,focusing on knickpoints and channel network reorganization from an area affected by the Haiyuan Fault in the northeastern Tibetan *** geomorphic indices,i.e.,drainage pattern andχanomalies,were calculated and *** re{3.lts show that two regional radial drainages formed around the Laohu and Hasi *** the interior of the radial drainage,tributaries from the southeast side of the Laohu Mountain experienced near 180°direction *** interpret this as the gradual drainage capture originating from the height difference(~190 m)of the local base level between the two *** tributaries from the Hasi Mountain show alternating gorges and broad valleys controlled by ***,tectonic uplift and the lowering of base level(from the incision of the Yellow River)triggered an autogenic positivefeedback transition from parallel to dendritic drainage *** observations {3.ggest that base level change and lithology play a crucial role in landscape evolution,even in a tectonically active region.

关键词： River piracy Base level lithology Geomorphic index Haiyuan Fault Northeastern Tibetan Plateau

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大沽河极端气候指数特征及其对地下水的影响

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中国农村水利水电 2024年第3期 50-61页

作者：李苏娜周鹏鹏王广才于晓曦周光扬冯衍扉中国地质大学(北京)水资源与环境学院北京100083 中国地质大学(北京)地下水循环与环境演化教育部重点实验室北京100083 青岛地质工程勘察院(青岛地质勘查开发局) 山东青岛266100 山东省地矿局城市地质与地下空间资源重点实验室山东青岛266100

掌握极端气候变化特征是地下水资源管理的重要环节。为了探究极端气候对地下水资源的影响,以大沽河水源地为例,基于40余年的气象数据,选取14个代表性的极端气候指标,并采用线性趋势法、Mann-Kendall突变检验、小波分析等方法分析了研究... 详细信息

掌握极端气候变化特征是地下水资源管理的重要环节。为了探究极端气候对地下水资源的影响,以大沽河水源地为例,基于40余年的气象数据,选取14个代表性的极端气候指标,并采用线性趋势法、Mann-Kendall突变检验、小波分析等方法分析了研究区气候变化的趋势性、突变性和周期性;基于极端气候指数和水文频率分析筛选了研究区代表性的极端气候年份,运用水均衡分析方法估算了极端气候年份条件下地下水平衡;并通过相关性和周期性分析评估了极端气候指数对地下水水位埋深的影响。结果表明:(1)1979-2021年,研究区内表征高温与降水的极端气候指数呈上升趋势,表征低温的极端气候指数总体呈下降趋势;极端丰水年代表性年份为2007年和2020年,极端枯水年代表性年份为1981年和1986年。(2)极端气候指数在20世纪90年代与21世纪初期发生突变,之后高温趋势更加显著。(3.极端降水指数第一周期对应的平均周期为11~16 a,极端气温指数第一主周期对应的平均周期主要有3.变化范围分别为20~24 a、12~14 a、5~6 a。(4)极端降水指数抑制地下水水位埋深的增加,极端降水量(R95p)和普通日降水强度(SDII)是影响大沽河水源地地下水水位埋深的主要降水指数;水位埋深的第一主周期对应的周期分别为13.15 a,与极端降水指数周期特征基本一致,意味着水位埋深受极端降水指数的影响较显著。(5)在极端丰水年(2007年),地下水总补给量约为3.9.4mm,总排泄量约为204.8 mm,均衡差约为114.6 mm;在极端枯水年(1981年),地下水总补给量约为104.2 mm,总排泄量约为141.1 mm,均衡差约为-3..9 mm。

关键词：极端气候指数极端气候年份趋势性突变性周期性地下水资源

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Ground-penetrating radar study of beach-ridge deposits in Huangqihai Lake, North China： the imprint of washover processes

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Frontiers of Earth Science 2016年第1期10卷 183-194页

作者： Xin SHAN Xinghe yu Peter D. CliFT Chengpeng TAN Shunli li Zhixing WANG Dongxu su School of Energy Resources China University of Geosciences (Beijing) Beijing 100083 China Department of geology and Geophysics Louisiana State University Baton Rouge LA 70803 USA

Determining the origin of beach ridges in lacustrine basins can often be problematic. The sedimen- tary processes responsible for formation of beach ridges on the north shore of Huangqihai Lake were investigated by using ground penetrating radar （GPR）. A 400 MHz GPR antenna was used to achieve a high vertical resolution of 0.044）.08 m. The radar stratigraphy was then determined using principles of seismic stratigraphy. The radar facies （RF） were determined by analyzing internal configuration and continuity of reflections, as well as reflection termination patterns. The identified RF fall into three groups （inclined, horizontal and irregular）. The inclined group consists of RF that display inclined reflections. The horizontal group consists of RF that exhibit predominantly horizontal reflections. In the irregular group, the reflections are typically weak. RF with reflections with gently landward dips in the shore-normal profile are interpreted as washover sheet deposits. RF with steeply landward-dipping and imbricated reflections are interpreted as washover lobes. Washover sheets develop when overwash fails to enter a significant body of water and sedimentation takes place entirely on the relatively flattened topography. Washover lobe development occurs when overwash enters a region in which topography dips steeply landward, and sedimentation takes place on the {3.rface of washover sheets or previous washover lobes. The beach-ridge deposits are interpreted as being formed entirely from vertically and laterally stacked washover sheets and washover lobes. They were formed by wave-dominated processes and secondary overwash processes {3.pplemented by longshore currents.

关键词： beach-ridge ground penetrating radar radar facies radar stratigraphy washover process

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Sedimentology and Sequence Stratigraphy of Marine to Lacustrine Deltaic Deposits in a Craton Basin and Their Controlling Factors: Shan 2 Member–He 8 Member(Guadalupian–Lopingian, Permian), Southeast Ordos Basin, North China

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 268-285页

作者： SHAN Xin yu Xinghe Peter CliFT li Yalong JIN lina su Dongxu DU Yonghui ZHOU Jinsong HAN Xiaoqin Key Laboratory of Marine Sedimentology and Environmental geology First Institute of Oceanography State Oceanic Administration Qingdao 266061 Shandong China Laboratory for Marine geology Qingdao National Laboratory for Marine Science and Technology Qingdao 266061 China School of Energy Resources China University of Geosciences Beijing 100083 China Department of geology and Geophysics Louisiana State University Baton Rouge 70803 USA School of Ocean and Earth Science Tongji University Shanghai 200092 China Research Institute of Shaanxi Yanchang Petroleum (Group) Company limited Xi 'an 710065 Shaanxi China

The Shan 2 Member, Shan 1 Member and He 8 Member of the Mid-Late Permian Shanxi and lower Xiashihezi formations, in the southeastern Ordos Basin, together comprise -150 m of deltaic deposits. This sequence records an overall evolution from deep marine environment to shallow lake associated with braided river, braided river delta and meandering river delta. Core description, well log interpretation, and stable isotope analysis, including carbon, oxygen and strontium, were conducted to understand the sedimentary evolution of Shan 2 to He 8 Member. The Shanxi Formation, which consists of the Shan 2 and Shan 1 members, is characterized by a tidal-influenced meandering river delta environment and a higher j13. value and S7Sr/S6Sr ratio and a lower jlSo value. The He 8 Member, the basal part of the Xiashihezi Formation, is featured by a braided river to braided river delta system and a lower j13. value, S7Sr/S6Sr ratio, and a higher jlSo value. Four third-order depositional sequences separated by five sequence boundaries are determined. Coarsening upward sequences of the Shan 2 Member-He 8 Member indicate a general regression trend, which can be correlated to global sea-level fall occurring during the Roadian-Wuchiapingian, as also evidenced by previous published zircon U-Pb results. The coal-bearing sequence （Shanxi Formation） to non-coal-bearing sequence （He 8 Member）, as well as a decrease of 87Sr/86Sr, suggest a trend from humid to arid climates. A combined effect of sea-level drop and a small uplift at the end of Shanxi Formation are proposed.

关键词： sequence stratigraphy sedimentary sequence delta marine to lacustrine evolution Roadian-Wuchiapingian Ordos Basin

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Metallogenetic epoch and mechanism of the tungsten ore in yushan, Beishan orogenic belt, Gansu

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Chinese Science Bulletin 2008年第8期53卷 1222-1230页

作者： ZHANG XinHu su li CUI XueJun DING ShuHong ZHANG JianGuo CHEN li School of Resources and Environment Lanzhou University Lanzhou 730000 China The Geological Lab Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Gansu Bureau of geology and Mineral Exploration and Development Lanzhou 730000 China No.4 Geological Exploration Institute Gansu Bureau of Geology and Mineral Exploration and Development Jiuquan 735000 China Gansu Institute of Geological survey Lanzhou 730000 China Laboratory of Electron Microscopy School of Physics Peking University Beijing 100871 China

Using SHRIMP zircon U-Pb dating methods and cathodoluminescence (CL) technique, we have pre- cisely dated ore samples from tungsten ore deposit, ore-bearing volcanic-sedimentary strata and granite in the yushan region within the east Tianshan-Beishan W-bearing zone. This study reveals yu- shan tungsten ore deposit zone formed in 250 ± 9 Ma, and it is closely associated with the Permian granites and felsic volcanic rocks. This new type of tungsten ore deposit in the east Tianshan-Beishang multiple-metallogenetic province may probably be associated with the regionally right-literal shearing after the main Carboniferous collisional orogeny, and the formation of pull-apart basin and the felsic magmatism.

关键词：甘肃钨矿石锆石二叠纪

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桂东北D/C界线沉积特征及对台盆相间演化的启示

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地质学报 2024年第4期98卷 1244-1262页

作者：吴亮君王璞珺吴继文韦盛亮户景松吕勇潘明周嘉铭林宇廖家飞韦伟韦艾辰李喜林苏光样吉林大学地球科学学院吉林长春130061 中国地质科学院岩溶地质研究所/自然资源部、广西岩溶动力学重点实验室广西桂林541004 联合国教科文组织国际岩溶研究中心/岩溶动力系统与全球变化国际联合研究中心广西桂林541004 中国地质大学(北京)地质过程与矿产资源国家重点实验室北京100083 广西壮族自治区区域地质调查研究院广西桂林541003 广西壮族自治区三一○核地质大队广西桂林541213

台盆相间是桂东北泥盆纪和石炭纪沉积的重要特色,而D/C界线又是台盆相间沉积最突出的一个时段之一。文章回顾并评述了桂东北D/C界线的研究历程、相序划分、主要代表剖面,认为桂东北D/C界线可划分为碎屑岩相序和碳酸盐岩相序以及它们的... 详细信息

台盆相间是桂东北泥盆纪和石炭纪沉积的重要特色,而D/C界线又是台盆相间沉积最突出的一个时段之一。文章回顾并评述了桂东北D/C界线的研究历程、相序划分、主要代表剖面,认为桂东北D/C界线可划分为碎屑岩相序和碳酸盐岩相序以及它们的过渡类型。通过对20条典型剖面的岩性组合特征对比,恢复了桂东北D/C界线海平面相对下降期的岩相古地理,结果显示桂东北在该时期主要存在柳州、桂林两大台地以及多个小型台地,台地间普遍发育快速相变的台沟、盆地沉积,石炭纪初期海水变浅,台地分布范围显著扩大,江南古陆供给增强,台盆相间格局迅速发展。为了进一步探讨桂东北D/C界线的演化过程和背后的控制因素,文章分析了广西整体的台盆相间演化的阶段性、同沉积构造作用以及海平面变化的影响,梳理了台盆相间演化过程中沉积环境分异与构造运动-海平面的关系,认为在滇黔桂裂谷盆地在持续断陷发展的前提下,桂东北D/C界线沉积分异的主要原因可能是受冈瓦纳大陆冰川形成与消融导致的海平面异常波动,以及柳江运动引发的局部同沉积断陷强度差异变动影响,且构造和沉积要素在D/C界线的耦合作用达到最强,最终促进桂东北台盆相间格局在D/C界线达到鼎盛。在此模式下,可以将台盆相间的演化划分为4个阶段,早泥盆世中期—晚期为台盆相间格局的孕育期,早泥盆世晚期—中泥盆世晚期沉积开始分异,为台盆相间格局的发展期,晩泥盆世—早石炭世台-盆出现强烈分割,海平面异常下降和柳江运动同时作用于沉积,为台盆相间格局的鼎盛期,早石炭世之后,台盆相间沉积维持了一定时期的强度,晚石炭世开始海水逐步恢复正常后台盆相间逐渐减弱,为台盆相间格局的衰退期。

关键词：台盆相间 D/C界线桂东北广西泥盆纪石炭纪古地理柳江运动

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Application of tensor CSAMT with high-power orthogonal signal sources in Jiama porphyry copper deposit,South Tibet

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China geology 2023年第1期6卷 37-49页

作者： Peng-liang yu Ting Qu Ri-zheng He Jian-li liu su-fen Wang Xiao-long Chen Shaanxi geology and Mining Geophysical and Geoehemical Prospecting Team Co. Ltd.Xi’an 710043China Chinese Academy of Geological Sciences Beijing 100037China

The Jiama porphyry copper deposit in Tibet is one of the proven supergiant copper deposits in the Qinghai-Tibet Plateau at present,with the reserves of geological resources equivalent to nearly 20×10^(6) ***,it features wavy and steep terrain,leading to extremely difficult field operation and heavy *** study attempts to determine the effects of the tensor controlled-source audiomagnetotellurics(CSAMT)with high-power orthogonal signal sources(also referred to as the high-power tensor CSAMT)when it is applied to the deep geophysical exploration in plateaus with complex terrain and mining areas with strong *** test results show that the high current provided by the highpower tensor CSAMT not only greatly improved the signal-to-noise ratio but also guaranteed that effective signals were received in the case of a long transmitter-receiver ***,the tensor data better described the anisotropy of deep geologic *** addition,the tests also show that when the transmitting current reaches 60 A,it is still guaranteed that strong enough signals can be received in the case of the transmitter-receiver distance of about 25 km,sounding curves show no near field effect,and effective exploration depth can reach 3.*** 2D inversion results are roughly consistent with drilling results,indicating that the high-power tensor CSAMT can be used to achieve nearly actual characteristics of underground electrical ***,this method has great potential for application in deep geophysical exploration in plateaus and mining areas with complex terrain and strong interference,*** study not only serves as important guidance on the prospecting in the Qinghai-Tibet Plateau but also can be used as positive references for deep mineral exploration in other areas.

关键词： Jiama porphyry copper deposit supergiant copper polymetallic deposit Tensor CSAMT of 150 kw High power 2D inversion Deep prospecting Mineral exploration engineering Xizang(Tibet)

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