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1.
本文采用从法国引进的Metravib热机械分析仪用正弦波加载方式,首次对四种不同孔隙度的饱和砂岩的衰减进行了实验研究,在5~400 Hz的频率,-50 ℃~100 ℃的温度范围获得衰减的热弛豫规律,由此求得它们的激活能和原子振动频率,其激活能和弛豫时间是处在原子和电子的激活能和弛豫时间之间.可见,在饱和岩石的晶粒间界缺陷处参与扩散的是原子、电子.并得出随孔隙度增大,衰减强度和激活能增大,原子的振动速率加快,弛豫时间缩短.在交变应力作用下,由多种矿物晶体胶结而成的饱和砂岩是一种多晶、多相的固体,由于内部结构复杂,损伤、缺陷广布,弛豫衰减是普遍存在的.饱和砂岩中存在的晶界、相界等许多缺陷,以及缺陷间的相互作用,比如饱和岩石中的饱和液体与岩石骨架之间的作用等等都可以产生弛豫衰减峰,弛豫过程还受晶界上原子扩散所控制.由于饱和岩石中的种种缺陷、相界等等导致上述矿物颗粒或晶界之间的多重弛豫,才使弛豫衰减峰变宽,分布宽度增大.用饱和砂岩中特有的饱和液体及砂岩内部结构的复杂性解释了饱和砂岩的衰减机理,很自然地将其宏观衰减特征与微细观结构紧紧联在一起.衰减及其机理的研究既具有科学意义,对地球物理勘探又具有实用价值. 相似文献
2.
Ren Wang 《Pure and Applied Geophysics》1995,145(3-4):403-423
The subject of geodynamics concerns the dynamics of the global motion of the earth, of the motion in the earth's interior and its interaction with surface features, together with mechanical processes in the deformation and rupture of geological structures. A brief historical review is given from Sir I. Newton, Maclauwin, Jacobi, Poincaré, Poisson, Lamé, Darwin, Rayleigh, and Love, who dealt with the homogeneous sphere, to Leibenson, Takeuchi, and Meinesz, concentrating on layered spheres, and after the advent of plate tectonics, on the use of numerical simulation, to the analyses of tectonic features, earthquake mechanism, the application of nonlinear dynamics. By discussing the forward and inverse mechanical problems, and the questions facing the inverse problems of searching for the structural parameters, driving forces, etc. are raised in more detail. Thereafter, some works accomplished in China on the global and regional stress fields analyses; tectonic features' analyses, mantle flow studies; experimental studies of rocks and their constitutive relations are presented. Finally, the interdisciplinary nature of the subject is emphasized, and the main mechanical problems that need special attention are then proposed. 相似文献
3.
水文连通性作为连接河湖水体间物质、能量及信息传递与交换的关键纽带,对水环境、水生态和生境状况具有联动与触发反馈作用,已成为水文学、水利学和生态学等诸多领域的研究热点.太湖流域作为全国典型的流域性密集平原河网区,在快速城镇化背景下,河湖水文连通关系变化剧烈并引起了一系列生态环境效应.本文以水文连通性概念与内涵为背景,对太湖流域水文连通性研究进行了综述.太湖流域水文连通性评价方法以图论法、景观格局指数及水文连通性函数等方法联合使用为主,且聚焦于区域尺度研究;演变过程按人类活动影响强度大致划分为自然水系形成阶段、古代人类活动影响阶段和现代人类活动影响阶段;气候变化和人类活动共同影响着太湖流域水文连通性变化,近百年来水利工程建设和城市化进程等人类活动的影响尤为剧烈;良好的水文连通性有利于汛期减轻流域洪涝灾害及非汛期保障水资源供给,但水文连通性的提高对水环境和水生态的效应由于涉及因素众多尚存在争议.针对当前研究现状和存在问题,提出(1)平原河网区水文连通性的定量表征与评估是水文连通性研究的前提;(2)定量解析流域水文连通性的驱动机制是水文连通性研究的重点;(3)深入跟踪大型引水调水工程对流域水文连通影响及其效应是一项长期任务;(4)兼顾环境生态效应的水利工程生态化改造研究,开展工程控制背景下的流域水文连通多目标优化调控,是实现太湖流域洪水调蓄、水资源供给、水环境净化、生物多样性维持等生态系统服务协同提升的重要途径. 相似文献
4.
塔里木南缘位于塔里木块体同青藏高原碰撞的前缘,是认识青藏高原同周围块体相互作用的重要位置.横波分裂方法可以获得岩石圈及软流圈地幔的介质各向异性特征,进而探讨岩石圈变形和地幔流动.本文利用横波分裂方法对中国科学院地质与地球物理研究所、北京大学和南方科技大学联合布设在塔里木盆地南部的8个宽频带流动地震台站记录的SKS和SKKS震相进行分析,获得了塔里木盆地南部上地幔各向异性参数.分析结果显示,研究区快波偏振方向总体比较一致呈近东西向,但存在盆地边缘到盆地内部变化,而慢波延迟时间分布在0.3~1.5 s,差异较大.综合前人对青藏高原北缘和阿尔金断裂周边的横波分裂研究结果,研究区内大部分地区地幔流动方向和绝对板块运动方向保持一致,推测青藏高原北缘同塔里木盆地接触带,青藏高原北缘软流圈南东东向流动对塔里木块体下方地幔流动造成扰动,随着深入到塔里木块体内部,干扰越来越弱;同时青藏高原北部软流圈物质可能对塔里木盆地岩石圈产生影响,随着地幔软流圈物质持续向北运动逐渐冷却,对盆地内部岩石圈的影响程度减弱. 相似文献
5.
通过室内动三轴试验,研究了西北地区遗址土体的动本构关系,得到了模型参数,分析了遗址土体的动剪模量比和阻尼比的特性,并通过归一化处理得出模型参数,结果表明:遗址土体符合Hardin-Dinevich双曲线模型,其相关系数均大于0.991 7,模型参数a、b与土样密度不存在相关性;在相同荷载下,密度越大,动应变和动残余应变越小,其中陕西定边陡沟子明长城墙体土承受动荷载能力下降较快,而草滩段秦长城墙体、瞭望台台基处初始弹性模量和初始剪切模量较小,三处土体硬度较小,易于遭受病害侵蚀破坏,需进行重点加固维护;遗址墙体所建窑洞处土体强度和硬度明显大于长城墙体,动弹性模量和动剪切模量约为其墙体2倍。草滩段瞭望台土体强度和硬度明显大于同地区长城墙体;遗址土体的动剪切模量G/G0随着动剪应变γd的增加而减小,且密度越大,衰减速度越快,阻尼比D随着动剪应变γd的增长,呈现先缓慢增加-急剧增加-缓慢增加的过程,且密度越大,阻尼比越大。按建造年代、建造形制和用途划分、所处地区对典型遗址进行动力特性的对比分析,为今后土遗址加固保护提供理论基础和参考依据。 相似文献
6.
气候变化叠加人类活动的双重影响下,西江流域的河川径流发生了不同程度的改变,重新认识和掌握变化环境下的径流时空演变规律对流域的科学管理具有重要意义。基于西江流域干支流7个控制性水文站近60年的日径流资料,综合极点对称模态分解法(ESMD)、Mann-Kendall检验、R/S分析、小波分析等方法,从年代、年、季和年内多个时间尺度对径流的时空演变特征进行分析,研究结果表明:年代尺度下,西江流域径流丰枯交替、变化悬殊,1970s与1990s径流丰沛,2010s径流偏枯,降雨影响着径流的丰枯变化,流域上、中游更易发生干旱与洪涝灾害;春、夏、秋、冬季径流振荡周期依次为2～7、15～20、28～29 a,3～5、7～10、20 a,2～3、6～8、12～15 a和3～8、12～15、20 a,均呈现年际与年代的双重周期特征,IMF1的年际振荡在径流变化中占主导地位;受降雨与水库调蓄作用的影响,年、夏、秋季径流呈下降趋势,预测下降变化具有持续性,春、冬季径流整体呈上升趋势。空间内上游的变化趋势更显著;年和季尺度径流在1980年后突变增多,尤其集中于2000—2010年间,人类活动与气候变化是造成西江... 相似文献
7.
叙述满洲里－绥芬河地学断面的地球物理成果．断面全长１３００ｋｍ，穿越了中国东北的大兴安岭岩浆岩带和张广才岭岩浆岩带，松辽盆地和海拉尔盆地，以及郯庐断裂北延部分的敦化－密山断裂、佳木斯－伊通断裂．结合地质资料，解释了断面多种地球物理方法的资料，包括重力、磁力、大地电磁（ＭＴ）、地震（广角地震测深、垂直反射地震与天然地震）、地热、古地磁以及综合解释，给出了断面岩石层构造的地球物理解释模型．讨论了松辽盆地基底的性质、莫霍界面的性质、大兴安岭重力梯级带的特征与成因，以及断面域地块拼合过程．研究结果认为，东北亚大地是一个拼合的增生大陆，是世界上一种新型的小地块碰撞拼合时受大洋板块俯冲的应力场作用形成的盆、山相间结构． 相似文献
8.
Silicate melts are very active in the interior of the Earth and other terrestrial planets, and are important carriers for the transport of material and energy. The determination of the equation of state(EOS) for silicate melts and the acquisition of a precise quantitative relationship between molar volume(or density) and temperature, pressure, and composition is essential for simulating the generation, migration, and eruption processes of magmas and the evolution of the magma ocean stage during the early formation of the Earth and other terrestrial planets, for calculating and modeling the phase equilibria involving silicate melts, and for revealing the variation of the microstructure of silicate melts with pressure. However, it is experimentally challenging to determine the volumetric properties of silicate melts and the accumulated density data at high pressure are still very limited due to a series of problems such as: the high liquidus temperature of silicate rocks; proneness for silicate melts to react with sample capsules to change the melt composition; and proneness for melts to flow and leak during the high pressure and high temperature experiments. In recent years, there is rapid progress in the high pressure and high temperature experimental techniques, in terms of not only the extension of temperature and pressure ranges but also the improvement on the accuracy of measurements, and the emergence of new methods for in-situ measurements. Here, we review the widely-used theoretical models of ambient-pressure and high-pressure EOS for silicate melts, and illustrate some problems that need to be solved urgently:(1) the room pressure EOS for iron-and titanium-bearing silicate melts needs to be improved;(2) the partial molar properties of the H2 O and CO2 components in silicate melts containing volatile components may vary markedly with the melt composition, which need to be addressed in high-pressure EOS;(3) how the formulation and applicable range of EOS correspond to changes in melt structure and compression mechanism requires further study. We highlight the basic principle and applicable range of various methods for determining the EOS for silicate melts, and compare the advantages and disadvantages of doublebob Archimedes method, fusion curve analysis, shock compression experiments, sink-float method, X-ray absorption, X-ray diffraction and ultrasonic interferometry. Future trends in this field are to develop experimental techniques for in situ measurements on melt density or sound velocity at high temperature and high pressure and to accumulate more experimental data,and on the other hand, to improve the theoretical models of the EOS for silicate melts by a combination of research on the microstructure and compression mechanisms of silicate melts. 相似文献
9.
今年是汶川地震十周年,2018年汶川特大地震给我国四川、甘肃等地区造成了巨大的灾难与伤痛,留下了宝贵的经验和教训,并给人以深刻警示。在灾后重建中结合受灾特点和当地经济发展现状,如何科学制订重建规划体系、创新重建模式和管理机制、加快重建速度,是高质量完成重建任务、大力改善民生、实现经济恢复振兴、促进社会和谐稳定的根本保证。同时,在重建中科学考虑潜在的地震灾害风险,最大限度地减少和避免地震灾害损失,采取务实可行的防震减灾对策也极为重要。本文概述十年前汶川特大地震对甘肃省造成的震害情况,基于甘肃灾区恢复重建的工作实践,阐明了甘肃灾区的重建原则和规划体系特点,从创新思想认识、强化社会管理、完善扶持政策、突出重建重点、提升基础能力、防范灾害风险等方面,分析总结灾后重建的主要措施与取得的成效,深刻反映了国家和地方政府在坚持科学执政、民主执政、依法执政、建设人民满意的服务型政府所取得的进步,也可为未来应对大震巨灾和各种自然灾害发生的重建工作提供重要的经验启示。 相似文献
10.
为进一步揭示阳澄湖入湖河道的污染物来源,提出相应的治理对策,以2017—2021年阳澄湖入湖河道水质监测数据为基础进行分析讨论。依据入湖水量选取10条主要入湖河道进行分析,其中位于阳澄湖东岸的白曲港在七浦塘拓浚工程建成之前主导流向为出湖,工程建成后,通过Pearson相关分析证实了其流向与七浦塘引水时的水力关系,因此白曲港被选为主要入湖河道。采用距平系数法、系统聚类法和物元分析法将阳澄湖主要入湖河道分为3个类别:第1类别包括白荡、蠡塘河、北河泾、永昌泾4条河道,第2类别包括渭泾塘、界泾和施家斗港3条河道,第3类别包括南消泾、七浦塘和白曲港3条河道。使用因子分析法进行因子分析,第1类别河道的因子为高锰酸盐指数(CODMn)、氨氮(NH3-N)、溶解氧(DO)和总磷(TP),第2类别河道的污染因子为NH3-N、总氮(TN)、pH、TP和DO,第3类别河道的污染因子为pH、TP、TN和DO。通过对上游河道水质情况分析、文件研究以及实地调查等方式得出第1类别河道区域的污染源主要为工业污染源和生活污染源,第2类别河道区域污染源主要为工业污染源与种植业污染源,第3类别河道污染源主要为陆地水产养殖污染源与种植业污染源。针对总体污染源情况,建议通过控制点源污染、削减面源污染、增强上游河道治理、开展生态治理修复以及加强巡查监管等方式对各类别河道区域进行针对性治理,以提高入湖河道水质,为阳澄湖的系统性和整体性治理打好基础。 相似文献
11.
三亚崖州湾是海南自贸港科技发展的前沿阵地,摸清其地质环境是科技发展规划的基础条件。选取水深、坡度、沉积物环境质量、古河道或古湖泊面积、沙波面积、沙脊面积、软土面积和软土厚度共8个影响因素,采用K-means聚类法、层次分析法和熵权法对研究区适宜性进行定量分区,共划分适宜性好、较好、中等、较差和差五个等级,分析不同影响因素对崖州湾适宜性的影响,总结五个分区的地质环境特征。研究结果表明适宜性最好区位于研究区中北部,其次是中南部,两翼地质环境质量最差,中等区镶嵌分布于崖州湾的外缘;建议优先考虑适宜性最好区进行规划开发,其次是适宜性较好区。文章先用K-means聚类法对影响因素分级,再用层次分析法和熵权法计算评价因子的主客观权重,形成一种主客观结合的科学评价方法,并运用到地质环境开发适宜性评价中,很好地划分出优选区。评价结果可为研究区开发规划及防灾减灾提供基础地质依据,同时具有良好的借鉴作用。 相似文献
12.
近年来,大地电磁法作为深部找矿与地球电性探测的感应类电法有了迅猛的发展,国内电磁法仪器基本上都是美、加、德三国地球物理公司所生产,中国已进口了几百套这些设备.随着中国国力的增强,地面电磁探测系统的自主研制被提到议事日程.从2010年开始,中国科学院地质与地球物理研究所牵头,联合中科院院内及高校等单位在国土资源部探测技术与实验研究专项(SinoProbe)中承担了《地面电磁探测(SEP)系统研制》项目的研究,目前已取得阶段性成果.本文详尽地论述了大地电磁法仪器发展现状、系统研究目标和总体设计,SEP发射系统、感应式磁传感器、分布式电磁数据采集系统、3D EM数据正反演成像软件和可视化数据管理软件、SEP系统集成和野外测试结果,最后对地面电磁探测系统研究进行了讨论、总结和展望. 相似文献
13.
We obtain the preliminary result of crustal deformation velocity field for the Chinese con-tinent by analyzing GPS data from the Crustal Motion Observation Network of China (CMONOC), particularly the data from the regional networks of CMONOC observed in 1999 and 2001. We de-lineate 9 tectonically active blocks and 2 broadly distributed deformation zones out of a denseGPS velocity field, and derive block motion Euler poles for the blocks and their relative motionrates. Our result reveals that there are 3 categories of deformation patterns in the Chinese conti-nent. The first category, associated with the interior of the Tibetan Plateau and the Tianshan oro-genic belt, shows broadly distributed deformation within the regions. The third category, associatedwith the Tarim Basin and the region east of the north-south seismic belt of China, shows block-likemotion, with deformation accommodated along the block boundaries only. The second category, mainly associated with the borderland of the Tibetan Plateau, such as the Qaidam, Qilian, Xining(in eastern Qinghai), and the Diamond-shaped (in western Sichuan and Yunnan) blocks, has thedeformation pattern between the first and the third, i.e. these regions appear to deform block-like,but with smaller sizes and less strength for the blocks. Based on the analysis of the lithosphericstructures and the deformation patterns of the regions above, we come to the inference that thedeformation modes of the Chinese continental crust are mainly controlled by the crustal structure.The crust of the eastern China and the Tarim Basin is mechanically strong, and its deformationtakes the form of relative motion between rigid blocks. On the other hand, the northward indentation of the Indian plate into the Asia continent has created the uplift of the Tibetan Plateau and the Tianshan Mountains, thickened their crust, and raised the temperature in the crust. The lower crust thus has become ductile, evidenced in low seismic velocity and high electric conductivity observed. The brittle part of the crust, driven by the visco-plastic flow of the lower crust, deforms extensively at all scales. The regions of the second category located at the borderland of the Tibetan Plateau are at the transition zone between the regions of the first and the third categories in terms of the crustal structure. Driven by the lateral boundary forces, their deformation style is also between the two, in the form of block motion and deformation with smaller blocks and less internal strength. 相似文献
14.
黄土物性指标可以近似但较为简便快速地评价其湿陷性。原状黄土在不同荷载和浸水的扰动下,随着其物性指标的改变,湿陷性也随之变化,故为了更好地评价这类扰动性黄土的湿陷性,在兰州东岗某场地上进行的两次相隔四十多年室内试验的基础上,采用相关分析的方法,研究扰动前后湿陷性系数与干密度、含水率、孔隙比、饱和度和塑性指数之间的关系。结果表明:(1)扰动前后湿陷性系数和干密度、含水率、饱和度和塑性均呈负相关,和孔隙比呈正相关,且扰动后湿陷性系数整体上低于扰动前,各指标对湿陷性系数的影响减弱。(2)以干密度、含水率、孔隙比、饱和度和塑性指数作为反映扰动前后黄土湿陷性的因子进行多元线性回归和因子权重分析,得出用以评价扰动前后黄土湿陷性的回归公式和影响湿陷性的因子排序。研究结果对于研判扰动黄土的湿陷性并选择合适的地基处理方法具有一定参考价值。 相似文献
15.
Abstract Damage, destruction and casualties related to landslide and debris flow are common phenomena in the Himalaya, especially during the summer monsoon. This fact was tragically illustrated on 22 July 1996, when Larcha, situated at the 109-km mark of the Arniko Highway, upper Bhotekoshi Valley, central Nepal, experienced a catastrophic debris flow powered by the Bhairab Kunda Stream. Of the 22 houses in Larcha, 16 were swept away, two were partially damaged and 54 people were killed in a matter of a few minutes. The event attracted attention when media linked it to a glacial lake outburst flood as a result of the fact that the source of the stream is a glacial lake. To understand the cause, initiation mechanism and deposition process, the basin area was studied from geological, geomorphologic and engineering geological points of view and the role of precipitation was evaluated. A combination of rainfall, runoff from cliff faces and stream undercutting triggered failure of the bedrock and colluvium, both on the dip and counter-dip slopes, 500 m upstream from the highway. The landslide debris dammed the channel, which was eventually breached, and deposited approximately 104 000 m3 of coarse debris, dominated by the metasediments of the Lesser Himalayan origin, and overwhelmed the village of Larcha. The debris deposit was studied for clast size, composition, texture and dimensions. Lack of sorting and the presence of abundant silt and clay in the source area helped in the initiation of debris flow. The abundance of the Lesser Himalayan metasediment clasts together with the absence of debris traces upstream from the landslide site ruled out the possibility of a glacial lake outburst flood. The disaster was a result of landslide damming triggered by precipitation and stream undercutting and sudden bursting. 相似文献
16.
社会救援力量业务的经费保障对社会救援队伍的建设至关重要。基于社会救援力量业务的经费保障现状,研究了为什么要进行社会救援力量业务经费保障,剖析了社会救援力量经费保障的不同阶段(经费筹措管理、经费日常管理、经费支出管理及经费监督管理)遇到的风险问题,并有针对性地提出了社会救援力量业务的经费保障风险防控优化对策。研究表明,开展此项研究有助于进一步丰富社会救援力量业务的经费保障理论体系,也有助于社会救援力量的持续健康发展。 相似文献
17.
湖冰光谱特征是湖冰遥感反演的物理基础,是研究湖冰光学特性和空间分布的理论依据。本文以查干湖为例,使用ASD Field Spec 4便携式地物光谱仪采集冰封期不同类型湖冰、积雪和水体光谱,利用Savitzky-Golay滤波法和包络线去除法分析白冰、灰冰、黑冰、雪冰、积雪和水体的反射光谱特征,探索气泡对湖冰反射光谱特征的影响。积雪和雪冰、白冰和灰冰、黑冰和水体的反射特征随着波长的变化特征基本一致,冰的反射率介于积雪和水体之间,其中白冰的反射率高于灰冰和黑冰,在包络线去除结果中,黑冰和水体在440 nm吸收谷处的吸收面积为5.184和10.878、吸收深度为0.052和0.106,雪、雪冰、白冰、灰冰在800和1030 nm吸收谷处的吸收面积和吸收深度的变化表现为雪<雪冰<灰冰<白冰。气泡是影响湖冰光谱特征的重要因素,气泡使白冰反射率减小和黑冰反射率增大,并且气泡使得白冰在800/1030nm和黑冰在440 nm处的吸收面积和吸收深度减小,其中气泡大小和疏密程度的不同会导致湖冰反射率的影响程度存在差异。同时,本文选取时间同步的Landsat 8 OLI遥感影像,在完成辐... 相似文献
18.
THE CRUSTAL SHALLOW STRUCTURES AND FAULT ACTIVITY DETECTION IN XINYI SECTION OF TAN-LU FAULT ZONE 
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下载免费PDF全文 GU Qin-ping XU Han-gang YAN Yun-xiang ZHAO Qi-guang LI Li-mei MENG Ke YANG Hao WANG Jin-yan JIANG Xin MA Dong-wei 《地震地质》1979,42(4):825-843
The Tan-Lu fault zone is the largest active tectonic zone in eastern China, with a complex history of formation and evolution, and it has a very important control effect on the regional structure, magmatic activity, the formation and distribution of mineral resources and modern seismic activity in eastern China. Xinyi City has a very important position as a segmental node in the Shandong and Suwan sections of the Tan-Lu fault zone. Predecessors have conducted research on the spatial distribution, occurrence and activity characteristics of the shallow crustal faults in the Suqian section of the Tan-Lu belt, and have obtained some new scientific understandings and results. However, due to different research objectives or limitations of research methods, previous researches have either focused on the deep crustal structure, or targeted on the Suqian section or other regions. However, the structural style and deep-shallow structural association characteristics of Xinyi section of Tan-Lu belt have not been well illustrated, nor its activity and spatial distribution have been systematically studied. In order to investigate the shallow crustal structure features, the fault activities, the spatial distribution and the relationship between deep and shallow structures of the Xinyi section of the Tan-Lu Fault, we used a method combining mid-deep/shallow seismic reflection exploration and first-break wave imaging. Firstly, a mid-deep seismic reflection profile with a length of 33km and a coverage number greater than 30 was completed in the south of Xinyi City. At the same time, using the first arrival wave on the common shot record, the tomographic study of the shallow crust structure was carried out. Secondly, three shallow seismic reflection profiles and one refraction tomography profile with high resolution across faults were presented. The results show that the Xinyi section of Tan-Lu fault zone is a fault zone composed of five concealed main faults, with a structural pattern of “two grabens sandwiched by a barrier”. The five main faults reveal more clearly the structural style of “one base between two cuts” of the Tan-Lu fault zone. From west to east, the distribution is as follows: on the west side, there are two high-angle faults, F4 and F3, with a slot-shaped fault block falling in the middle, forming the western graben. In the middle, F3 and F2, two normal faults with opposite dip directions, are bounded and the middle discontinuity disk rises relatively to form a barrier. On the east side, F2 and F1, two conjugate high-angle faults, constitute the eastern graben. The mid-deep and shallow seismic reflection profiles indicate that the main faults of the Xinyi section of Tan-Lu fault zone have a consistent upper-lower relationship and obvious Quaternary activities, which play a significant role in controlling the characteristics of graben-barrier structure and thickness of Cenozoic strata. The shape of the reflective interface of the stratum and the characteristics of the shallow part of the fault revealed by shallow seismic reflection profiles are clear. The Mohe-Lingcheng Fault, Xinyi-Xindian Fault, Malingshan-Chonggangshan Fault and Shanzuokou-Sihong Fault not only broke the top surface of the bedrock, but also are hidden active faults since Quaternary, especially the Malingshan-Chonggangshan Fault which shows strong activity characteristics of Holocene. The results of this paper provide a seismological basis for an in-depth understanding of the deep dynamics process of Xinyi City and its surrounding areas, and for studying the deep-shallow tectonic association and its activity in the the Xinyi section of the Tan-Lu Fault. 相似文献
19.
寒区土与结构接触面冻结强度可以视为是与土性、温度、含水量、界面粗糙度、法向压力等诸多因素直接相关的复杂函数形式,并直接影响到上部结构的承载能力及稳定性。以青藏高原黏土与不同粗糙度的钢板结构接触面为研究对象,通过不同含水率、不同温度及不同法向压力下冻结黏土与钢板结构接触面的直剪正交试验,研究土与结构接触面冻结强度的影响因素及影响程度大小,并对冻结强度的变化规律进行初步分析和探讨。研究结果表明含水量对抗剪强度的影响最大,在不同影响因素共同作用下,界面抗剪强度最小值为0.13 MPa,最大值为0.45 MPa。界面抗剪强度随含水量的增加、温度的升高而明显降低,随界面法向压力和粗糙度的增大呈明显增大趋势。界面强度基本可通过摩尔-库仑准则,利用界面的黏聚力和内摩擦角进行表示,并在文中给出了界面强度的参考值。 相似文献