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Mesozoic basin evolution and tectonic mechanism in Yanshan, china

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Science china Earth Sciences 2004年第Z2期47卷 24-38页

作者： LIU Shaofeng1,2. LI Zhong3.& ZHANG Jinfang4 1. Key Laboratory of Lithospheric Tectonics, Deep-Level Process and Explovation, Ministry of Education of P. R. china, Beijing {2., china 2. {3. of geosciences and Resources, china university of geosciences, Beijing {2., china 3. Institute of Geology and geophysics, Chinese Academy of Sciences, Beijing 10002., china 4. Institute of Software, Chinese Academy of Science, Beijing 100080, china Key Laboratory of Lithospheric Tectonics Deep-Level Process and Explovation Ministry of Education of P.R.ChinaBeijing 100083 China school of geosciences and Resources China University of Geosciences Beijing 100083 China Institute of Geology and geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Software Chinese Academy of Science Beijing 100080 China

The Mesozoic basins in Yanshan, china underwent several important tectonic transformations, including changes from a pre-Late Triassic marginal cratonic basin to a Late Triassic-Late Jurassic flexural basin and then to a late Late Jurassic-Early Cretaceous rift basin. In response to two violent intraplate deformation at Late Triassic and Late Jurassic, coarse fluvial depositional systems in Xingshikou and Tuchengzi Formations were deposited in front of thrust belts. Controlled by transform and extension faulting, fan deltas and lacustrine systems were deposited in Early Cretaceous basins. The composition of clastic debris in Late Triassic and Late Jurassic flexural basins respectively represents unroofing processes from Proterozoic to Archean and from early deposited, overlying pyroclastic rocks to basement rocks in provenance areas. Restored protobasins were gradually migrated toward nearly NEE to EW-trending from Early Jurassic to early Late Jurassic. The Early Cretaceous basins with a NNE-trending crossed over early-formed basins. The Early-Late Jurassic and Early Cretaceous basins were respectively controlled by different tectonic mechanisms.

关键词： Yanshan, Mesozoic, depositional provenance of basin, unroofing of provenance, basin evolution, tectonic mechanism.

Suggestion of a dynamic model of North china basin-range system

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Progress in Natural Science:Materials International 2003年第4期 73-82页

作者： SHAO Ji'an, ZHANG Changhou, ZHANG Luqiao, and ZHANG Yongbei (1. school of Earth and Space Sciences, Peking university, Beijing 100871,{2. 2.{3., Beijing 100873.{2. 3. Inner-Mongolia Institute of Geology, Hohhot 01002.,{2. 4. Institute of Geology and geophysics, Chinese A-cademy of Sciences, Beijing 10002.,{2.) school of Earth and Space Sciences Peking University Beijing 100871 China china university of {2. Beijing 100873 China Inner-Mongolia Institute of Geology Hohhot 010020 China Institute of Geology and geophysics Chinese Academy of Sciences Beijing 100029 China

It is found from preliminary studies that previous basin-range models have difficulties in explaining the formation of theMesozoic North-china basin-range system. This work suggests a new model-" tectonic thermal erosion" model, which considers the North china basin of Late Mesozoic and its peripheral ranges as a unified system, identifies relationship between upwelling and lateral spreading of the asthenolith with horizontal rnovement and deformation of the upper crust in the system, clarifies the effects of underplat-ing erosion on the crustal evolution, and tries to establish an earth-dynamic modei of the North china Mesozoic basin-range supported by numerical simulation.

关键词： North china Mesozoic-Cenozoic basin-range system.

A review of the New geophysics:a new understanding of pre-fracturing deformation in the crack-critical crust with implications for hydrocarbon production

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Petroleum Science 2008年第1期5卷 1-12页

作者： Stuart Crampin Yuan Gao school of geosciences University of Edinburgh UK Edinburgh Anisotropy Project British Geological Survey Edinburgh UK Institute of Earthquake Science China Earthquake Administration Beijing China

This paper reviews a new understanding of shear-wave splitting （seismic-birefringence） that is a fundamental revision of conventional fluid-rock deformation. It is a New geophysics with implications for almost all solid-earth geosciences, including hydrocarbon exploration and production, and earthquake forecasting. Widespread observations of shear-wave splitting show that deformation in in situ rocks is controlled by stress-aligned fluid-saturated grain-boundary cracks and preferentially orientated pores and pore-throats pervasive in almost all igneous, metamorphic, and sedimentary rocks in the Earth＇s crust. These fluid-saturated microcracks are the most compliant elements of the rock-mass and control rock deformation. The degree of splitting shows that the microcracks in almost all rocks are so closely spaced that they verge on fracture-criticality and failure by fracturing, and are critical {2. with the “butterfly wing＇s” sensitivity of all critical {2.. As a result of this crack-criticality, evolution of fluid-saturated stress-aligned microcracked rock under changing conditions can be modelled with anisotropic poroelasticity （APE）. Consequently, low-level deformation can be： monitored with shear-wave splitting; future behaviour calculated with APE; future behaviour predicted with APE, if the change in conditions can be quantified; and in principle, future behaviour controlled by feed-back. This paper reviews our current understanding of the New geophysics of low-level pre-fracturing deformation.

关键词： Crack anisotropy New geophysics pre-fracturing deformation seismic birefringence,shear-wave splitting

Tectonic evolution of the Dabieshan orogen: In the view from polyphase deformation of the Beihuaiyang metamorphic zone

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Science china Earth Sciences 2005年第7期48卷 886-899页

作者： LIN Wei1, 2. Faure Michel3. WANG Qingchen1 & Arnaud Nicolas4 1. LTE, Institute of Geology and geophysics, Chinese Academy of Sciences, Beijing 10002.,{2. 2. Department of Earth and Planetary Sciences, Graduate school of Science, Nagoya {3., Japan 3. ISTO, UMR CNRS 6113. Batiment Géosciences, Orléans Université d’Orléans, 45067 Orléans Cedex 2. France 4. UMR 652. "Magmas et Volcans", 5 Rue Kessler, 63.00 Clermont-Ferrand, France LTE Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Earth and Planetary Sciences Graduate School of Science Nagoya University Japan ISTO UMR CNRS 6113 Orléans Université d'Orléans 45067 Orléans Cedex 2 France UMR 652. Magmas et Volcans 63000 Clermont-Ferrand 5 Rue Kessler France

The Beihuaiyang metamorphic zone was formed by the Early Mesozoic collision of the North and South china Blocks. It consisted of the Foziling and Luzhenguan complexes and was thought to have never afforded a deep subduction. A similar feature of the deformation in the Dabieshan UHP metamorphic rocks implies that these different tectonic units share the same geodynamic background. The early stage of deformation can be preserved on account of their relatively shallower subduction than that for UHP rocks. On the basis of an analysis of the geo- logical structure and geochronological results, five deformational stages have been recognized: a D1-Early compressional deformation which represents the continental subduction; a D2.Early exhumation deformation producing a syn-convergence exhumation; a D3.Main deformation, represented by an exhumation deformation with Late Triassic age; a D4-Doming and its margin extensional gravity collapse deformation and finally a D5-regional extensional deformation of Cretaceous that was mostly introduced by the migmatization and plutonism.

关键词： Beihuaiyang metamorphic zone geometry kinematic polyphase deformation tectonic evolution.

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超声实验中谱比法衰减的散射与本征吸收特性

地球物理学报 2018年第3期61卷 1083-1094页

作者：周浩符力耘矿产地球化学国家重点实验室中国科学院地球化学研究所贵阳550002 中国科学院大学北京100049 中国石油大学(华东)地球科学与技术学院青岛266580

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法... 详细信息

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法测量的弹性波衰减,简称谱比法衰减,由介质的本征吸收特性和非均质散射特性共同决定.然而,在谱比法理论中,没有将这两种衰减特性的作用区分对待.因此,实验室测量的谱比法衰减中是否含有散射特性,其散射特性是否可以忽略,常不明确.本文基于对岩石物理实验中样品波形特征的基本认识,通过能流理论描述了弹性波的本征吸收和非均质散射过程,以及对应的尾波形成机理.文章还应用能流理论测量岩石的弹性波衰减,即能流法衰减.无论是通过理论推导,还是通过实验验证,谱比法衰减与能流法衰减都显示出良好的一致性.这两种直达波衰减的一致性暗示了谱比法衰减中存在着两种衰减特性.文中还对比分析了谱比法衰减与喷射流本征衰减的实验结果,该结果同样展示了谱比法衰减中可能存在着散射特性.因此,通过能流理论,可以利用样品波形的尾波特征定性判断谱比法衰减中可能存在的散射特性.即异常明显的尾波振幅可能意味着强烈的直达波非均质散射,谱比法衰减中的散射特性因而不可忽略.

关键词：谱比法散射衰减本征衰减尾波

Ce Anomalies of the Yangtze Region,South china,through the Ordovician and Silurian Transition

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Journal of Earth Science 2009年第6期20卷 941-948页

作者：严德天张丽琴李双建 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of GeosciencesWuhan Institute of Geology and geophysics Chinese Academy of Sciences school of Geodesy and Geomatics Wuhan University Key Laboratory of Geospace Environment & Geodesy of Ministry of Education Wuhan University Petroleum Exploration and Production Institute of SINOPEC

Systematic Ce anomalies for whole-rock have been obtained from the shale-dominated, continuous, and pelagic sedimentary sequences spanning the Ordovician/Silurian （O/S） boundary at the Tieshui （铁水） of Xiushan （秀山）, Chongqing （重庆）, South china. Ce anomalies across the O/S boundary are recognized in three intervals, Wufeng （五峰）, Guanyinqiao （观音桥） and Longmaxi （龙马溪）. The calculated Ce/Ce＊ values of Wufeng Formation range from 0.84 to 0.96 （avg. 0.90）. In the Guanyinqiao Formation, the values of calculated Ce/Ce＊ range from 0.73.to 0.85 （avg. 0.79）. The Ce/Ce＊ values of uppermost Longmaxi Formation range from 0.87 to 0.96 （avg. 0.91）. All along the section, the magnitude of the Ce anomaly is always negative, but is more significant in the Guanyinqiao Formation. The relatively higher Ce/Ce＊ values in the Wufeng and Longmaxi shales are likely to be due to the sediments deposited under rather reducing conditions. The Ce anomaly apparently does play some regular roles in the anoxic events that accompany prominent mass extinctions, and this work provides new data of critical importance for constraining models on the end-Ordovician anoxic events and mass extinctions.

关键词： Ce anomaly redox mass extinction Ordovician/Silurian boundary Yangtze platform.

Gravity Changes Before Large Earthquakes in china: 1998-2.05

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地球空间信息科学学报（英文） 2011年第1期14卷 1-9页

作者： ZHAN F. Benjamin ZHU Yiqing NING Jinsheng ZHOU Jiangcun LIANG Weifeng XU Yunma school of Resource and Envirorunental Science Wuhan University 129 Luoyu Road Wuhan 430079 China Texas Center for Geographic Information Science Texas State University San Marcos TX 78666 USA Institute of Geodesy and geophysics Chinese Academy of Sciences 340 Xudong Street Wuhan 430077 China Second Crust Monitoring and Application Center China Earthquake Administration Xi'An 710054 China school of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2.00, 2.02. and 2.05 at stations of the Crustal Movement Observation Network of china (CMONOC) and examined gravity changes be-fore the occurrence of nine large (Ms≥6.8) earthquakes that ruptured within or near china's Mainland and Taiwan from November 2.01 to August 2.08. Results from this analysis show that significant gravity changes occurred across a large region before each of these nine large earthquakes, and these changes were detected by repeated ground gravity surveys through CMONOC. Although these gravity changes were significant, more research is needed to investigate whether these gravity changes could be viewed as precursors of large earthquakes. Limitations and uncertainties in the data include sparseness of the gravity monitoring network, long time intervals between consecutive gravity surveys, inevitable measurement errors, hydrological effects on gravity, and effects of vertical crustal movements on gravity. Based on these observations, we make several recommendations about possible future direc-tions in earthquake-related research using gravity monitoring data.

关键词： earthquake gravity seismology china Wenchuan geodesy GIS

金沙江奔子栏-达日河段大型泥石流堆积扇的成因机制

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山地学报 2011年第3期29卷 312-319页

作者：陈剑崔之久戴福初许冲中国地质大学(北京)工程技术学院北京大学城市与环境学系中国科学院地质与地球物理研究所青藏高原研究室

金沙江上游奔子栏-达日河段属横断山区的干热河谷地带,河谷沿岸大型古泥石流堆积扇广泛发育,其成因却一直没有得到很好的研究。对该区瓦卡大型古泥石流堆积物进行了沉积结构、粒度、地球化学和孢粉等分析,揭示了泥石流的沉积环境及其形... 详细信息

金沙江上游奔子栏-达日河段属横断山区的干热河谷地带,河谷沿岸大型古泥石流堆积扇广泛发育,其成因却一直没有得到很好的研究。对该区瓦卡大型古泥石流堆积物进行了沉积结构、粒度、地球化学和孢粉等分析,揭示了泥石流的沉积环境及其形成过程。通过粗颗粒石英的光释光单片再生法(SAR)测年研究,获得金沙江上游奔子栏-达日河段古泥石流大规模暴发的年代为12.600~4 500 a BP。丰富的风化碎屑物源、陡峻的地形及雨季降水集中是该区古泥石流形成的主要原因。全新世早期青藏高原东南缘受西南季风加强的影响,气候趋于暖湿,季节性暴雨增加。金沙江上游干热河谷区大型泥石流堆积扇的发育年代暗示其是全新世早期西南季风加强作用下的地貌响应。从地质灾害防治的角度,由于现代气候因素导致泥石流灾害的频度和规模较小,预防该区地质灾害的重点应是防止人工砍伐树木和不合理的人工切坡导致对地表环境的破坏加剧。

关键词：金沙江干热河谷泥石流堆积扇气候变化

Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi Corridor, NW china Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANCongrong LIUJinfeng ZHANGJunyan KeyLaboratoryofWesternEnvironmentalChanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China InstituteofGeologyandgeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-2.5(long )]drilling cores covering the past 13. kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern china, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(2..4)( )]kyr~[(2..8)( )]kyr), Laschamp Event ([(43.3.( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)2.( )]kyr) and the Blake Event (12..4 kyr^113.3.kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern china. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-2.0( )]Here,[( )-2.0( )]we tentatively[( )-2.0( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern china