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The subducted slab of Yangtze Continental block beneath the Tethyan orogen in western Yunnan

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Chinese Science Bulletin 2000年第5期45卷 466-472,481页

作者： futian liu Jianhua liu Dalai Zhong Jiankun He Qingyu You Chinese Acad Sci Inst Geol & Geophys Beijing 100101 Peoples R China

The western Yunnan area is a natural laboratory with fully developed and best preserved Tethyan orogen in the world. Seismic tomography reveals a slab-like high velocity anomaly down to 250 km beneath the western Yunnan Tethyan orogen, to its west there is a low-velocity column about 300 km wide. in the region from Lancangjiang to Mojiang an obvious low velocity in the lower crust and uppermost mantle overlies on the slab. Synthesizing the available geological and geochemical results, the present paper demonstrates that this slab-like high velocity anomaly is a part of the subducted plate of Yangtze Continental segment after the closure of Paleotethys. The collision of India and Eurasia continent starting from 50-60 MaBP might trigger thermal disturbance in the upper mantle and cause the uprising of asthenosphere, in that case the subducted Yangtze plate could be broken off, causing Cenozoic magmatic activities and underplating in the Lancangjiang-Mojiang region.

关键词： seismic tomography Tethyan orogen in western Yunnan subduction remains of Yangtze Block.

Relationship between Mesozoic Magmatism and Subduction in the Da Hinggan-Yanshan Area

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Acta Geologica Sinica(English Edition) 2001年第1期75卷 1-8页

作者： SHAO Ji'an liu futian CHEN Hui HAN Qingjun Peking University Beijing 100871 Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100101

High-resolution tomographic images of the belt crossing the Japan Trench-Changbai Mountains-Dong Ujimqin Qi are represented in this paper, revealing the shape of a subducted slab in the western Pacific region and characteristics of the lithospheric structures under the Changbai Mountains and the Da Hinggan Mountains. Studies of the spatial distribution, subduction time and the time-lag between the subduction and magmatism, combined with petrology and isotope geochemistry of the Late Mesozoic volcano-plutonic rocks from the Da Hinggan Mountains-Yanshan Mountains have further proved the independence of magmatic activities from the subduction of the Pacific plate. The Mesozoic tectono-thermal evolutionary history and structural characteristics of the lithosphere in the Da Hinggan Mountains and North China suggest that the formation and evolution of magma have probably a close relationship with the delamination and thinning of the continental lithosphere and the underplating resulting from the consequent upwelling of the asthenosphere. On the other hand, the large-scale strike-slip fault system, resulting from sinistral shearing of the Pacific plate relative to the Asian continent in the Mesozoic, is responsible for the formation and emplacement of magma on the continental margin. It was the intense crust-mantle interaction, together with structural deformation at the shallower levels that led to the large tectono-magmatic belt in the East Asian continental margin.

关键词： Da Hinggan-Yanshan Mountains volcanic-plutonic rock subduction tomographic image

Structure of the crust and uppermost mantle from broadband seismic array in the western Dabie Mountains,east central China

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Science China Earth Sciences 2009年第2期52卷 203-212页

作者： LI Hua WANG LiangShu LI Cheng liu futian HU DeZhao YU DaYong Department of Earth Sciences Nanjing UniversityNanjing 210093China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

A broadband seismic array of 7 stations was set up in the western Dabie Mountains (31°20′-31°50′N, 114°30′-115°E). Teleseismic events from May 2001 to November 2001 were collected and analyzed by radial receiver function to determine the S-wave velocity structure of the crust and uppermost mantle. The crustal thickness is 32-38 km beneath the array. The crust-mantle boundary appears as a gently north-dipping velocity discontinuity, but turns to be a velocity gradient beneath a station near the Qiliping shear zone in the south of the array. In the north of the array, a large offset of 4-6 km exists in the Moho along the Tongbai-Tongcheng shear zone, suggesting a suture zone formed by the northward subduction of the Yangtze plate beneath the North China plate. Along the Tongbai-Tongcheng shear zone, a north-dipping, EW-striking low-velocity zone was observed in the upper mantle, which may be related to the collision boundary between the Yangtze and the North China plates in the Triassic. Therefore the Tongbai-Tongcheng shear zone is the southern boundary of suture zone between the Yangtze and the North China plates. In the south of the array, a high-velocity body in the lower crust near the Qiliping shear zone probably results from the underplate of mafic magma into the lower crust, which is generally associated with large-scale extension triggered by delamination of the thickened crust.

关键词： Dabie Mountains receiver functions S-wave velocity lithosphere structure

Seismic tomography showing subduction and slab breakoff of the Yangtze block beneath the Dabie-Sulu orogenic belt

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Chinese Science Bulletin 2000年第1期45卷 70-74页

作者： Peifen Xu Ruomei Sun futian liu Qingchen Wang Bolin Cong Chinese Acad Sci Inst Geol & Geophys Beijing 100101 Peoples R China

Seismic tomography reveals that a subducted ancient block has been preserved beneath the Moho of the Dabie-Sulu orogenic belt. Taking into account of geological and geochronological data, we inferred from the tomographic images that the Yangtze block was subducted northward beneath the Sino-Korean block and broken off at the depth <200 km during 200-190 Ma. The slab breakoff of the Yangtze block is the most important dynamic mechanism to control the exhumation of UHP rocks.

关键词： seismic tomography slab breakoff of the Yangtze block exhumation of UHP rocks Dabie-Sulu orogenic belt.

Influence on lacustrine source rock by hydrothermal fluid： a case study of the Chang 7 oil shale, southern Ordos Basin

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Acta Geochimica 2018年第2期37卷 215-227页

作者： Delu Li Rongxi Li Zengwu Zhu Xiaoli Wu futian liu Bangsheng Zhao Baoping Wang School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China Yanchang Oilfiled Co. Ltd Yan'an 716000 China

Hydrothermal fluid activity during sedimenta- tion of the Triassic Yanchang Formation in the Ordos Basin and the impact of said activity on formation and preservation conditions of source rocks have received little attention. Oil yield, major element, trace element, rare earth element, and total sulfur （TS） data from the oil shale within the Yanchang are here presented and discussed in the context of hydrothermal influence. Oil shale samples returned relatively high total organic carbon （TOC）, in the range of 4.69%-25.48%. A high correlation between TS and TOC suggests TS in the oil shale is dominated by organic sulfur and affected by organic matter. The low Al/ Si ratio of oil shale samples implies quartz is a major mineralogical component. Si/（Si ＋ Al ＋ Fe） values suggest close proximity of the oil shale to a terrigenous source. δEu; Fe versus Mn versus （Cu ＋ Co ＋ Ni）× 10; and SiO2/（K2O ＋ Na2O） versus MnO/TiO2, Fe/Ti, and （Fe ＋ Mn）/Ti are evidence of hydrothermal fluid activity during oil shale sedimentation, and δU and U/Th of the oil shale indicate reducing conditions. The Sr/Ba of oil shale samples suggests fresh-water deposition. The high correlations of Fe/Ti and （Fe ＋ Mn）/Ti with δU, U/Th, and TS demonstrate that hydrothermal fluid activity promotes reducing conditions. Sr/Ba ratios had low correlation with Fe/Ti and （Fe ＋ Mn）/Ti, implying that hydrothermal fluid activity had little impact （Fe ＋ Mn）/Ti, δU, U/Th, and on paleosalinity. Fe/Ti, Cu ＋ Pb ＋ Zn all exhibited high positive correlation coefficients with TOC in oil shale samples, suggesting that more intense hydrothermal fluid activity improves conditions in favor of formation and preservation of organic matter.

关键词： Hydrothermal fluid activity Lacustrine source rock Element geochemistry Chang 7 Ordos Basin

Study on oil–source correlation by analyzing organic geochemistry characteristics: a case study of the Upper Triassic Yanchang Formation in the south of Ordos Basin, China

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Acta Geochimica 2016年第4期35卷 408-420页

作者： Delu Li Rongxi Li Baoping Wang Zhi liu Xiaoli Wu futian liu Bangsheng Zhao Jinghua Cheng Wenbin Kang School of Earth Sciences and Resources Chang’an University Yanchang Oilfield Co. Ltd

In the south of the Ordos Basin, the oil source of the Upper Triassic Yanchang Formation is confused all the time, which affects further exploration. In this study, oil sources from the oil layers of Ch6, Ch8 and Ch9 are all analyzed and confirmed. Through their carbon isotope value and biomarkers, characteristics of crude oils from the Yanchang Formation are analyzed. Then, the oil–source relation is discussed, with the source rocks' ***, the oil–source relation is calculated through cluster analysis. It is believed that the oils from the Yanchang Formation deposit in a similar redox environment, with weak oxidation–weak reduction, and have all entered maturity stage. Ch9 crude oil is more mature than crude oils from Ch6 and Ch8, and has more advanced plants and fewer algae. Gas chromatography(GC) and gas chromatography–mass spectrometry(GC–MS) analysis show that crude oils from Ch6 and Ch8 may come from Ch7, and Ch9 crude oil may not. Cluster analysis displays that crude oils from Ch6 and Ch8 have closer squared Euclidean distance with Ch7 source rocks than Ch9 crude oil does,indicating crude oils from Ch6 and Ch8 stem from Ch7 source rocks. And Ch9 crude oil has rather close squared Euclidean distance with Ch9 source rocks, illustrating Ch9 crude oil may be from Ch9 source rocks. This research may provide the theoretical basis for the next exploration deploy in the south of Ordos Basin.

关键词： Carbon isotope correlation - Cluster analysis Basin Introduction Biomarker Oil-source Yanchang Formation - Ordos

Elemental characteristics and paleoenvironment reconstruction： a case study of the Triassic lacustrine Zhangjiatan oil shale, southern Ordos Basin, China

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Acta Geochimica 2018年第1期37卷 134-150页

作者： Delu Li Rongxi Li Zengwu Zhu Xiaoli Wu futian liu Bangsheng Zhao Jinghua Cheng Baoping Wang School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China Yanchang Oilfiled Co. Ltd Yah'an 716000 China

Using trace elements to reconstruct paleoenvironment is a current hot topic in geochemistry. Through analytical tests of oil yield, ash yield, calorific value, total sulfur, major elements, trace elements, and X-ray diffraction, the quality, mineral content, occurrence mode of elements, and paleoenvironment of the Zhangjiatan oil shale of the Triassic Yanchang Formation in the southern Ordos Basin were studied. The analyses revealed relatively high oil yield(average 6.63%) and medium quality. The mineral content in the oil shale was mainly clay minerals,quartz, feldspar, and pyrite; an illite–smectite mixed layer comprised the major proportion of clay minerals. Compared with marine oil shale in China, the Zhangjiatan oil shale had higher contents of quartz, feldspar, and clay minerals, and lower calcite content. Silica was mainly in quartz and Fe was associated with organic matter, which is different from marine oil shale. The form of calcium varied. Cluster analyses indicated that Fe, Cu, U, V, Zn, As,Cs, Cd, Mo, Ga, Pb, Co, Ni, Cr, Sc, P, and Mn are associated with organic matter while Ca, Na, Sr, Ba, Si, Zr, K,Al, B, Mg, and Ti are mostly terrigenous. Sr/Cu, Ba/Al, V/(V+ Ni), U/Th, AU, and δU of oil shale samples suggest the paleoclimate was warm and humid, paleoproductivity of the lake was relatively high during deposition of the shale—which mainly occurred in fresh water—and the paleo-redox condition was dominated by reducing conditions. Fe/Ti ratios of the oil shale samples suggest clear hydrothermal influence in the eastern portion of the study area and less conspicuous hydrothermal influence in the western portion.

关键词： Trace elements Occurrence mode Paleoenvironment Zhangjiatan oil shale Yanchang Formation Ordos Basin

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风力发电机组振动状态监测及故障诊断分析

科学技术创新 2024年第18期 58-61页

作者：张宪杨万强刘富田郭纾怡国家电投集团电站运营技术(北京)有限公司北京

分析了风力发电机传动部件常见故障及原因,针对当前风力发电机组振动状态监测及故障诊断系统普遍功能局限、智能化程度低的问题,以LabVIEW开发平台为依托,设计了一款智能化的风力发电机组振动监测与故障诊断系统,以供借鉴。

关键词：风力发电机组争端状态检测故障诊断 LabVIEW

内蒙古内陆河流域地下水资源评价及相关地质环境问题分析

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华北地质 2024年第2期47卷 62-72页

作者：宁航柳富田王国明张竞张卓陈社明中国地质调查局天津地质调查中心(华北地质科技创新中心) 天津300170 天津市海岸带地质过程与环境安全重点实验室天津300170

【研究目的】为提升对内蒙古内陆河流域水文地质和地下水资源的认知程度,提高地下水资源利用效率,减少地质环境问题。【研究方法】本文以内蒙古内陆河流域为主要工作区,查明了该流域的补径排特征及水文地质条件,收集并整理了该流域近20... 详细信息

【研究目的】为提升对内蒙古内陆河流域水文地质和地下水资源的认知程度,提高地下水资源利用效率,减少地质环境问题。【研究方法】本文以内蒙古内陆河流域为主要工作区,查明了该流域的补径排特征及水文地质条件,收集并整理了该流域近20年来的气象及地下水开发利用等相关资料,更新了地下水资源评价相关水文地质参数,对该流域地下水资源补排项进行汇总分析,对流域内山丘区和平原区分别采用排泄量法和补给量法进行地下水资源评价。同时全面论述了该流域地下水动态变化特征,并探讨了与地下水相关的湖泊萎缩、土地荒漠化等生态地质环境问题。【研究结果】计算得出内陆河流域地下水资源总量为37.94亿m^(3),年际上坝上地区浅层地下水位大致经历了先升高后降低的总趋势,地下水位年内总体呈现周期性波动的趋势,受地下水位影响流域内湖泊萎缩严重,沙质荒漠化面积减小,而盐碱质荒漠化逐渐加剧。【结论】该研究为该区水资源的可持续开发利用与生态环境保护提供了基础资料和科学依据。

关键词：内蒙古内陆河流域地下水资源量地下水动态特征地质环境问题