利用GPS观测结果研究华北地区现今构造应力场

根据１９９２年和１９９５年两期ＧＰＳ测量结果所获得的位移场和应变场,结合丰富的地质资料,利用有限元方法对华北地区现今构造应力进行了模拟。计算结果表明;华北地区现今构造应力场主压应力方向为ＮＥＥ,其边界力除受ＮＥ５５°－ＳＷ２３５°方向的压应力作用外,同时还受到ＳＥ１２０°－ＮＷ３００°方向的拉张力作用,其中ＮＥ－ＳＷ的压应力量值较大,约为ＳＥ－ＮＷ向拉应力的两倍,这个结果与震源机制解所获得的应力场     

利用水位资料反演华北地区构造应力场变化

本文选取华北地区观测条件较好的63口水位观测井资料, 运用小波分析法去除各井水位资料中的短期高频信息, 提取出能反映水位多年动态变化的趋势信息, 并利用各井水位趋势变化数据反演出华北地区多年构造应力场变化图像, 结合其它水文资料, 探讨了华北地区近年来的构造应力场变化特征。     

华北地区三维构造应力场

根据最新的地质构造、地球物理、原地应力测量以及震源机制解资料,建立了华北地区三维构造应力场模型;对华北地区构造应力场的三维图象进行了模拟计算;分析研究了区域构造应力场的总体特征和局部分区特性;并讨论了华北构造块体的动力边界条件、活动断裂构造和地壳物性分区等因素对华北构造应力场的控制和影响．     

山东地区现今构造应力场与地震活动

应用现代中小地震的震源机制解,推断了山东地区的现今构造应力场,分析了区域构造应力场整体与局部变化特点。在此基础上,探讨了区域构造应力场与地震活动的关系。     

灵山地区地震活动性及构造应力场

本文以广西及其邻近地区较为丰富的历史及现今的地震资料为基础,用地震能流密度的方法对灵山地区的地震活动水平作了定量的研究。对该区地震的震源深度作了估计,并用多种方法对灵山地区的构造应力场作了较详细的研究。     

华北地区震源断层与深浅构造关系的初步研究

使用地震资料（等震线、地表破裂带、地形变、余震平面和剖面分布及震源机制）描述强震震源断层的立体特征。发现震源断层的上界即为由地震测深资料得到的Ｇ界面，并与该界面之下的高倾角深断裂吻合，证明地震时深断裂发生了剪切错动。震源断层与Ｇ界面之上的铲形正断层构成不连接的两套断裂系统，它们之间存在有对应和无对应的复杂关系。     

乌鲁木齐地区构造应力场与中强震活动特征研究

为了做好中强地震的震预报和震后趋快速判定工作,利用乌鲁木齐地区中强震震源机制解,小震平均震源机制解以及Ｓ波偏振方向综合研究了该区域应力场的分布和中强地震的活动特征。     

长江峡东地区构造应力场与地震活动的讨论

本文在分析峡东地区中、新生代构造应力场演化的基础上、根据构造形变、水系分布、震源机制与地球物理场特征和应力实测、模拟实验等多种途径综合分析了现代构造应力环境，认为本区现今处在大范围引张力背景上迭加了北东－南亚向压应力的联合作用，由此决定了中强地震的活动特点及其发震断裂系统。     

乌鲁木齐地区现今构造应力场综合分析

乌鲁木齐地处天山中段.震源机制解研究表明,北天山中段区域主压应力方向为N10°E左右,且具有自西向东逐渐东偏的特点.在乌鲁木齐地区,由中强地震震源机制解反演的主压应力方向为N15°-20°E;由断层滑动资料反演的乌鲁木齐周边构造应力场的主压应力方向为N17°W-N2°E.上述两种资料反演的乌鲁木齐构造应力场主压应力方向...     

Preliminary analysis on the tectonic stress level in the source region of Tangshan earthquake

Introduction Analyzing tectonic stress field based on focal mechanism data is an important way to the study tectonic evolvement of lithosphere and associated dynamic process. Such studies growrapidly in China and abroad (Zoback, 1992; Plenefisch, Bonjer, 1997; XU, 1985; CUI, XIE, 1999). At present most of the studies focus on the inversion of focal mechanism data for the direction and relative magnitude of stress tensor, and few on absolute stress. Using focal mechanism and fault scratch,…     

Basic characteristics of recent tectonic stress field in southwest China

Direction and structure characteristics of 58 tectonic stress tensors have been determined in 41 surveyed areas (points) in the southwestern district of China through a calculation method for inversion of tectonic stress tensors from sliding direction of faults, and, in combination with seismic mechanism solution andin-situ stress measurements, the following characteristics of the recent tectonic stress fields in the southwestern district of China have been defined: (1) the stress fields in this district have remained stable since the end of early to mid-Pleistocene; (2) the effect of such tectonic stresses is mainly horizontal; (3) the orientation of the maximum principal stress axis shows a trend of regular rotation from north to south, i. e. from NEE-SWW in northern Songpan and Longmen Shan areas to sub-EW in the central part of western Sichuan, and further to NNW-SWW or sub-SN in Yunnan; (4) the regional tectonic stress fields are of distinct division character; (5) there is well concordance between the main direction and type of stress structures in the stress tate both in deep and shallow parts of the crust. In addition, studies of staged tectonic stress tensors preliminarily show that in early Quaternary the southwestern district was mainly affected by lateral compression of Indian plate, under which the regional tectonic stress fields mainly display NE-sub-EW compression. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 407–417, 1993.     

Three dimensional tectonic stress field in North China

IntroductionThecrusttectonicstressfieldisoneofthekeyproblemsofgeodynamics,itsmaincontentsareaprobingintospatialdistributionanddynamicevaluationofcrusttectonicstressfield,thentracingtheevolutionprocessofcrusttectonicmovement,learningcontemporarycrusttectoniceventanditsmechanism,thuspredictingthefuturedevelopmentlawoftectonicmovement.Intheendof1970s,aseriesofpaperswerepublishedattheinternationalconferenceonMagnitudeofDeviatoricStressesintheEarth'SCrustandUppermostMantle.Theygavethebriefoutlin…     

中国大陆现代构造应力场与强震活动

依据应力性状和力源特征,中国大陆现代构造应力场可划分为四级应力区.它们分别是2个一级应力区、4个二级应力区、5个三级应力区和26个四级应力区.通过分析中国大陆现代构造应力分区与强震活动之问的关系,初步获得以下结论:①构造应力作用强烈和复杂的地区是强震频发的地区;②应力区边界是强震集中发生的地带;③应力方向、应力结构类型...     

兰州至玛曲地区地应力测量与现今构造应力场特征研究

兰州—玛曲地区是印度板块北东向推挤引起青藏块体强烈变形的前缘区,该区的现今构造应力场研究对研究大陆动力学问题具有重要意义.本文给出了兰州—玛曲地区不同地点的现今地应力实测值的大小和方向.测量方法采用压磁应力解除法,测点分别布置在阿姨山、大水、尕海、玛艾以及清水.为系统研究本区及邻近地区现今构造应力场特征,对已有应力实测数据进行了整理分析.研究结果表明,本区及邻区几十米浅表部应力与其他地区相比,属于中等大小量值;应力随深度增加而加大,但在不同构造单元,应力增加梯度有所不同;最大水平主应力方向总体上为北东向,不同构造单元上方向有所不同,鄂尔多斯地块最大水平主应力方向为近东西向,河西走廊带最大水平主应力方向在北北西—北东方向内变化,祁连山东南端最大水平主应力方向变化较大,西秦岭地块是现今地应力的一个过渡带,最大水平主应力方向由北侧的NE向逐渐转变为中部的EW向和南侧的SEE向.本文给出的结果与由GPS观测给出的该区域应变场分布具有一致性.     

Recent tectonic stress field zoning in Sichuan-Yunnan region and its dynamic interest

In this paper, we have carefully determined the stress zones in the Sichuan-Yunnan region with reference to the in-situ stress data of hydraulic fracturing and the inverted fault slip data by using the step-by-step convergence method for stress zoning based on focal mechanism solutions. The results indicate that the tectonic stress field in the Sichuan-Yunnan region is divided into 3 stress zones by 2 approximately parallel NNW-trending stress transition belts. The area between the 2 belts is the Sichuan-Yunnan stress zone where the maximum principal stress σ1 is just in the NNW direction. The eastern boundary of Sichuan-Yunnan stress zone （the eastern stress transition belt） is basically consistent with the eastern boundary of Sichuan-Yunnan rhombic block. The western boundary of Sichuan-Yunnan stress zone （the western stress transition belt） is not totally consistent with the western boundary of Sichuan-Yunnan rhombic block. The northern segment of the western stress transition belt extends basically along the Jinshajiang fault and accords with the western boundary of Sichuan-Yunnan rhombic block, while its southern segment does not extend along the southwestern boundary of the rhombic block, i.e., Honghe fault and converge with the eastern stress transition belt, but stretches continuously in the NNW direction and accords with the Yingpanshan fault. We therefore consider that under the combined influence from the northward motion of India Plate, the southeastward shift of east Qinghai-Xizang Plateau and the strong obstruction of South China block, the tectonic stress field in the Sichuan-Yunnan region might not be totally controlled by the previous tectonic frame and new stress transition belt may have possibly formed.     

Evolution of 3D tectonic stress field and fault movement in North China

IntroductionThe research on stress field interior the Earth is an either relative old or young branch of geoscience. Early in the 20th century, in order to learn the state of inner stress field, a few scholars had used simple ideal model to analyze big scale tectonic conformations and activities according to tide, gravity, rotation and inner thermal materials. So far, lots of problems on the state of the Earth stress field have not been solved completely yet. The origin of stress field, the d…     

Modern tectonic stress field in Southwest Yunnan, China

IntroductionSouthwest Yunnan region is located in the southeastern margin of Qinghai-Tibet Plateau, bordering on the Sichuan-Yunnan rhomboidal block in the east and on the northeast corner of Indian Plate in the northwest. It is one of the regions of intense tectonic activities and frequent strong earthquakes in China continent. To study the features of modern tectonic stress field of this region is of significance for revealing the evolution mechanisms of Tibetan Plateau as well as for un…