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Cenozoic magmatic activity and oblique uplifting of the Ailao Mountain: Evidence from a short-period dense seismic array

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Science China Earth Sciences 2020年第9期63卷 1294-1308页

作者： Lu ZHANG Zhiming BAI Tao XU zhenbo wu Minfu HUANG Guiping YU Junlei CHEN Mengjie ZHENG State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China School of Geophysics Chengdu University of TechonologyChengdu 610059China Earthquake Administration of Yunnan Province Kunming 650224China

Geological studies show that the southern part of Ailaoshan-Red River shear zone(ALSRRSZ)has experienced complex metallogenic processes and multi-stage non-uniform uplifting,called oblique uplifting since the *** detect the deep structure and geodynamic background beneath Daping,Chang’an and other gold and polymetallic deposits in this area,we carried out a high-density short-period seismic array survey in southern Yunnan *** array used is approximately240 km long with an interval of 500 m between two adjacent *** on the data collected by the array,we used H-κstacking and common conversion point(CCP)methods of receiver functions to reveal the fine crustal structure beneath this array,which was located from Lvchun(western end)to the east and ended in *** three main conclusions are as follows.(1)The average crustal thickness is approximately 37 km and the Vp/Vsratio is ***,the thickness and Vp/Vsratio of the Ailao Mountain are rather greater or higher than those of the western Lanping-Simao Basin and eastern South-China *** results may indicate that the crust is rich in ferromagnesian minerals or has a thermal fluid anomaly after orogenic movement.(2)There are two obvious inclined interfaces beneath the Ailao Mountain in the mid-upper crust,which suggests that strong deformation occurred there during the orogenic *** evidences,such as the weak converted-wave Pms phase from the Moho,low P-wave velocities of the upper mantle,high surface heat flow values,and generally developed hot springs,indicate that a strong crust-mantle interaction exists in the southern segments of the Ailaoshan-Red River shear *** interactions include a diapir of mantle-sourced magma(stronger in the east than that in the west),lateral collision from the Indian Plate,and the differential uplift caused by the strike-slip movement of the Red River *** of above deep processes led to the Cenozoic oblique uplifting of Ailao Mounta

关键词： Ailaoshan-Red River shear zone Multiform metal deposits Oblique uplifting Short-period dense seismic array Receiver function

Seismic traveltime inversion of 3D velocity model with triangulated interfaces

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Earthquake Science 2014年第2期27卷 127-136页

作者： Fei Li Tao Xu Minghui Zhang zhenbo wu Chenglong wu Zhongjie Zhang Jiwen Teng State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks,which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block,and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization,which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block *** damped least squares method is employed in seismic traveltime inversion,which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model.

关键词： Traveltime inversion 3D Triangulated interface Block modeling

Directed pulsed neutron source generation from inverse kinematic reactions driven by intense lasers

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Matter and Radiation at Extremes 2024年第6期9卷 19-28页

作者： Yilin Yao zhenbo wu Tao Ye Shaoping Zhu Xiantu He Bin Qiao Center for Applied Physics and Technology HEDPS and State Key Laboratory of Nuclear Physics and TechnologySchool of PhysicsPeking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China Frontiers Science Center for Nano-Optoelectronics Peking UniversityBeijing 100094China

Neutron production driven by intense lasers utilizing inverse kinematic reactions is explored self-consistently by a combination of particle-in-cell simulations for laser-driven ion acceleration and Monte Carlo nuclear reaction simulations for neutron *** is proposed that laser-driven light-sail acceleration from ultrathin lithium foils can provide an energetic lithium-ion beam as the projectile bombarding a light hydrocarbon target with sufficiently high flux for the inverse p(^(7)Li,n)reaction to be efficiently ***-dimensional self-consistent simulations show that a forward-directed pulsed neutron source with ultrashort pulse duration 3 ns,small divergence angle 260,and extremely high peak flux 3×10^(14)n/(cm^(2)·s)can be produced by petawatt lasers at intensities of 10^(21)W/cm^(2).These results indicate that a laser-driven neutron source based on inverse kinematics has promise as a novel compact pulsed neutron generator for practical applications,since the it can operate in a safe and repetitive way with almost no undesirable radiation.

关键词： inverse intense acceleration

DETERMINATION OF SHEAR STRENGTH OF SOIL OF SLIDE ZONE

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Scientia Geologica Sinica 1998年第2期 85-90页

作者： Liu zhenbo and wu Faquan Engineering Geomechanics Lab, Chinese Academy of Sciences, Beijing 100029

１．ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｄｓｌｉｄｅｉｓａｇｅｏｌｏｇｉｃａｌｈａｚａｒｄｃａｕｓｅｄｂｙｎａｔｕｒａｌｆａｃｔｏｒｓｏｒｈｕｍａｎｅｎｇｉｎｅｅｒｉｎｇａｃｔｉｖｉｔｉｅｓ．Ｉｔｄｉｓｔｒｉｂｕｔｅｄｗｉ...

１．ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｄｓｌｉｄｅｉｓａｇｅｏｌｏｇｉｃａｌｈａｚａｒｄｃａｕｓｅｄｂｙｎａｔｕｒａｌｆａｃｔｏｒｓｏｒｈｕｍａｎｅｎｇｉｎｅｅｒｉｎｇａｃｔｉｖｉｔｉｅｓ．ＩｔｄｉｓｔｒｉｂｕｔｅｄｗｉｄｅｌｙｉｎｓｏｕｔｈｗｅｓｔＣｈ...

关键词：

Crustal structure across the Kunlun fault from passive source seismic pro filing in East Tibet

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Crustal structure across the Kunlun fault from passive sourc...

Seismic traveltime inversion of 3D velocity model with triangulated interfaces

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Tao Xu zhenbo wu Zhongjie Zhang Xiaobo Tian Yangfan Deng Chenglong wu Jiwen Teng State Key Laboratory of Lithosphere Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences

The crust beneath the northeastern(NE) Tibetan Plateau records the imprints on Paleozoic Kunlun orogen and far field effects from continental collision and convergence between the Indian and Eurasian plates. A passive source seismic pro file was conducted across eastern Kunlun mountains(also called Animaqing suture belt). Receiver function imaging and H-k stacking results with this dataset demonstrate that(1) crust slightly thins from about 64 km under the Songpan–Ganzi terrane to about 56–62 km under the Qaidam–Kunlun block and the Qilian block;(2) Moho topography is relatively smooth with gradual undulation beneath east Kunlun orogeny belt, in contrast to 2–5 km Moho step at the AKMS/Kunlun fault from previous deep seismic soundings or even no Moho topography variation from recent deep seismic re flection pro filing;(3) the average crustal Vp/Vs ratios display an increasing trend to the Kunlun fault belt from 1.76 to 1.85 in Songpan–Ganzi terrane, while decreases from 1.83 to 1.65 away from the fault belt in Qaidam–Kunlun block;(4) The high Vp/Vs ratio in Songpan–Ganzi terrane, is similar to previous results from the pro file across Longmenshan fault belt. The normal to low Vp/Vs ratio distribution in Qaidam–Kunlun block supports the viewpoint that the deformation occurring in NE Tibet is predominated by upper-crustal thickening;and(5) the thickness of non-seismogenic layer varies slightly about 40 km between 90° and 100°E, then decreases to less than 20 km around 106°E along the Kunlun fault. The change of the non-seismogenic layer thickness is consistent with the change of the lower crust thickness derived from deep seismic sounding. The increased crustal thickness may be due to the differences in the thickness of the crust of the two plates before their collision, and/or largely achieved by thickening of the lower crust, perhaps indicating a crust flow mechanism operating more strongly in the western region.

关键词： Crustal structure Kunlun fault Passive source Receiver function Common conversion point(CCP) stack Vp/Vs velocity ratio

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Seismic traveltime inversion of 3D velocity model with trian...

基于动态RCS的无人飞行器隐身突防航迹规划

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks, which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block, and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization, which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block *** damped least squares method is employed in seismic traveltime inversion, which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model.

关键词： Traveltime inversion 3D Triangulated interface Block modeling

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华中科技大学学报（自然科学版） 2022年第11期50卷 72-78页

作者：蔡超葛超武振波李振华中科技大学人工智能与自动化学院湖北武汉430074 北京机电工程研究所北京100074

针对传统航迹规划方法通常不考虑无人飞行器(UAV)的飞行姿态对其被雷达发现的概率的影响问题,提出一种基于动态雷达散射截面(RCS)的无人飞行器隐身突防航迹规划方法.首先,结合UAV的运动学模型和动态RCS特性,建立雷达制导防御系统下的突... 详细信息

针对传统航迹规划方法通常不考虑无人飞行器(UAV)的飞行姿态对其被雷达发现的概率的影响问题,提出一种基于动态雷达散射截面(RCS)的无人飞行器隐身突防航迹规划方法.首先,结合UAV的运动学模型和动态RCS特性,建立雷达制导防御系统下的突防模型;进一步,采用稀疏A^(*)算法对UAV的空间位置及飞行姿态进行搜索,将满足突防准则的扩展点加入搜索空间,并引入通视性分析方法计算扩展点的预估代价.仿真结果表明:该方法在多种假定条件下均能快速规划出低发现概率的隐身航迹;UAV通过位姿调整,能有效躲避预警机等动态威胁的探测,提高突防能力.

关键词：无人飞行器(UAV) 航迹规划动态雷达散射截面(RCS)特性稀疏A^(*)算法通视性分析

A successive three-point perturbation method for fast ray tracing in complex 2D and 3D geological models

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A successive three-point perturbation method for fast ray tr...

2011—2015年神经外科患者脑脊液分离菌分布及耐药分析

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Tao Xu Fei Li zhenbo wu Chenglong wu Ergen Gao Bing Zhou Zhongjie Zhang Guoming Xu State Key Laboratory of Lithosphere Evolution Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Disaster Prevention Department of Geology and Geophysics The University of Adelaide School of Earth and Space Sciences University of Science and Technology of China

This paper presents new 2D and 3D ray-tracing methods that can be applied to traveltime and ray path computations for transmitted, re flected and turning seismic waves in complex geologic models. The new ray-tracing scheme combines segmentally iterative ray tracing(SIRT) and pseudo-bending methods to address both stratified and arbitrarily shaped block models. The new method robustly extends our previous constant block models and constant gradient block models to generally heterogeneous block models, and incorporates cubic splines or triangulated interfaces to boundaries of complex geological bodies. The method is thus more widely applicable to practical problems. A successive three-point perturbation scheme is formulated that iteratively updates the midpoints of a segment based on an initial ray path. The midpoints are corrected by applying first-order analytic formulae to locations of the midpoint inside the block or on the boundaries of the blocks, which are then updated with the pseudo-bending method and SIRT algorithm instead of the traditional iterative methods. Empirical applications, including an example addressing the Bohemian Massif, demonstrate that this successive three-point perturbation scheme successfully performs kinematic ray tracing in heterogeneous complex 2D and 3D media.

关键词： Three-point perturbation method Ray tracing 2D and 3D Block model Heterogeneous velocity

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中华急诊医学杂志 2017年第12期26卷 1384-1388页

作者：吴振波周宏伟陈坤浙江大学医学院附属邵逸夫医院下沙院区杭州310018 浙江大学医学院附属第二医院杭州310009 浙江大学公共卫生学院杭州310058

目的了解神经外科患者脑脊液分离菌株的分布及耐药情况，为临床颅内感染的预防和经验用药提供依据。方法对2011年1月至2015年12月浙江大学医学院附属第二医院神经外科患者脑脊液标本的分离菌株情况及其药敏结果进行分析。结果脑脊液送检... 详细信息

目的了解神经外科患者脑脊液分离菌株的分布及耐药情况，为临床颅内感染的预防和经验用药提供依据。方法对2011年1月至2015年12月浙江大学医学院附属第二医院神经外科患者脑脊液标本的分离菌株情况及其药敏结果进行分析。结果脑脊液送检共23株259份，培养分离菌株1060株，培养阳性率为4．56％。l060株菌株剔除重复菌株后得到419株样本，其中革兰阳性菌103株（24．6％），革兰阴性菌293株（69．9％），真菌23（5．5％）。居前3位的分离菌株分别为不动杆菌属（165株，39．4％），肺炎克雷伯菌（72株，17．2％），凝固酶阴性葡萄球菌（54株，13．6％）。其中鲍曼不动杆菌耐药严重，对美罗培南耐药率82．3％，对头孢哌酮确}巴坦耐药率76．4％，仅对多黏菌素和阿米卡星耐药率低，分别为3．1％和29．8％。肺炎克雷伯菌耐药严重，对美罗培南耐药率72．6％，对头孢哌酮一舒巴坦耐药率79．0％，仅对多黏菌素和阿米卡星耐药率低，分别为0％和35．2％。葡萄球菌中耐甲氧西林金黄色葡萄球菌（MRSA）、耐甲氧西林表皮葡萄球菌（MRSE）以及耐甲氧西林溶血葡萄球菌（MRSH）检出率分别为76．5％、100．O％和100．0％，检出率高。未发现万古霉素和替考拉宁不敏感的葡萄球菌属。结论革兰阴性菌为脑脊液主要分离菌，鲍曼不动杆菌和肺炎克雷伯菌检出率高、耐药情况严重，临床应对脑脊液分离菌株分布及耐药情况多加关注，并根据耐药分析结果合理使用抗生素。

关键词：颅内感染脑脊液病原菌耐药性抗菌药物

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