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1.
赣南主要断裂构造及其与中强地震关系 总被引：1，自引：0，他引：1
赣南地质构造十分复杂,具有发生中强地震的地质构造背景。通过数年来的调查研究,在赣南范围内,从发震构造背景来看,对地震影响颇大的构造体系是:通过寻邬、会昌、瑞金、石城的河源—邵武北北东向新华夏系断裂构造带;大余—兴国北东向华夏系断裂构造带;三南(全南、龙南、定南)—寻邬东西向构造复合带;环状构造等,它们都是历次构造运动产生单一的断裂破碎带或由若干断裂组合的复武褶皱断裂带。目中生代以来由于构造力逐渐强化,积累起来的能量释放是多方面的,有的是沿断裂带相对 相似文献
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分析和对比中国大陆布格重力异常水平梯度的彩色图像，得到一些新的构造特征信息. 大致以105°E为界，图像的东部以蓝色低梯度为背景，出现中、高梯度带状构造和大梯度差值边界的线状构造；西部以高、中梯度的带状构造为格架，镶嵌着低梯度区，区内有阴影线状构造. 总体上，重力异常水平梯度构造可概括为三大组. 第一组是NNE向的大兴安岭、太行山、武陵山高梯度带与斜切东部全区的郯庐大断裂带和NNW向的斜切西部全区的三条大断裂带；第二组为西部的NWW向与NEE向高、中梯度带的交叉构造格局，以及东部近于等间距的三条NWW向断续的阴影构造带和一条单一的构造线，而华南则仅有NE向的低梯度构造线；第三组是横贯全区的的几条近EW向和中部SN向宽而复杂的构造带，在后者的东、西两侧散臣着大间距、小长度、断续的SN向阴影构造线. 这三组重力梯度构造不仅反映了地貌起伏的信息，而且显示了大区域构造，特别是深部构造的密度差. 各组线状构造带的内部结构和各组的形成时间及演变历史可能不同，但它们相互复合构成现今总体的构造格局，对大尺度现代构造应力场作用都会有不同的响应，因此导致主应力方向的区域性变化. 相似文献
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我省就地震活动的范畴而言,属华北地震带,从大地构造部位上讲属祁吕贺山字型构造体系前弧的东翼,祁吕系呈北东向斜贯全省,与新华夏构造体系复合。南端和秦岭,北端和阴山纬向构造带相接,中间分布着一系列的断陷盆地,断陷盆地之间均被横向隆起相隔。仔细分析每个断陷盆地,它们的走向并非一致,大同、太原、运城三盆地其走向为北东向,而忻定、临汾二盆地则近乎南北向。各个隆起区的两侧或四周大部分为高角度的正断层,这也说明了断距大,影响深。最近形变测量证实,隆起区仍在上升,而盆地则仍在长趋势下沉。这些复杂的构造特征正是我省地震活动频繁的地质背景。 相似文献
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长江三峡地区新生代以来地壳应力场的基本特征 总被引：2，自引：0，他引：2
根据白垩－第三纪红层中构造变形实际观测及水系统计资料，计算了三峡地区新生代和新构造期分区及区域应力场的主应力方向。结果表明：方压应力为北东东向，主张应力为北北西向，现代构造应力场与新生代以来应力场基本一致。 相似文献
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本文以航磁资料为基础,详细地探讨了南北地震带的磁性构造特征及其与地震活动的关系。指出在构造层次上浅部多为北西、北东向的构造网络复合,深部则呈南北向、东西向构造带相互正交迭加。其内的地震活动与构造环境之间关系密切,地震的活动范围和强度明显受其浅部、深部构造的影响和控制。 相似文献
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舟山群岛地区的地质构造背景 总被引：3，自引：0，他引：3
从大地构造、磁场和新构造分区特点等方面，对舟山群岛地区的地质构造背景作了较为详细的论述，指出该区处于基底构造交汇，新构造和地震活动强弱分区的过渡地带，新构造运动在中更新世之后趋于平稳；全新世为间歇性活动，强度较弱，基底由若干微块体组成，块体间为不稳定边界，舟山群岛及其海域深部以东西向、浅表部以北东和北东向构造为主，具有孕震和发震的地质构造背景。 相似文献
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构造楔入目前正在使加州中部谷地西缘岩石变形，中生代大谷地群的弧前盆地地层的构造关系表明，早期的构造楔入是与弗朗西斯科杂岩向西俯冲和增生同时的，由于构造楔体的挤离作用会阻止增生楔物体向深部迁移，目前的构造楔体几何形状与弗朗西斯科杂岩中的蓝片岩变质是不相容的，我们提出一个构造序列来协调这种构造过程。 相似文献
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运用波浪镶嵌构造观点，对临汾盆地的构造背景和地震活动规律进行了探讨，认为临汾盆地正好位于环太平洋波系和特提斯波系壳下次级构造隆起的叠加部位，其地震活动明显受这２大波系的控制，即临汾大地震是在２大波系构造同时强烈活动时发生的，单方向构造活动，不足以引发临汾大地震。认为临汾盆地大震活动的周期约４００年，其活跃期约１００年，平静期约３００年。 相似文献
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四川省甘孜地区地处青藏高原东南侧,因受到印度板块的强烈挤压,构造运动十分强烈,境内发育着多组北西或北北西向深大断裂,沿断裂带分布着众多的温泉,其中构造复合地段和构造的交叉转折部位温泉尤为发育,不少温泉还受次一级构造和不同岩性所控制。多数温泉出露在断裂附近或背斜的张裂隙中。据不完全统计,全州较大泉点多达六十多处(图1)。它 相似文献
10.
近３０年来于临汾盆地对３００年前的临汾大震发震构造虽作过大量实地考察、研究，但至今仍有不同认识和存疑。考虑到继续以临汾论临汾恐难获新识，本文另辟新径，从华北、乃至中国东部更大范围类似地震构造环境所取得的大震（Ｍ≥７．４）发震构造的某些共性，应用地质类比方法，在论证临汾地区存在ＮＥ向控震背景基础上，进而评述和探讨了临汾大震的可能发震构造。 相似文献
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As is known, the secular deceleration of the Earth's diurnal rotation is explained mainly by the tidal friction in the ocean. Below we consider this mechanism in some detail, taking into account also elastic deformations of the mantle under the action of ocean loading and the interaction between the tide-generating body, ocean tidal wave, liquid outer core, and solid inner core. It is shown that elastic displacements of the core-mantle boundary under the action of ocean loading are of about the same amplitude and phase as the elastic loading displacements of the Earth's outer surface. As a result, side by side with the mechanism of secular deceleration of diurnal rotation of the mantle, there are also (1) the opposite mechanism of secular acceleration of diurnal rotation of the outer liquid core and of the solid inner core and (2) the mechanism of excitation of differential rotation in the liquid core. Taking these effects into account, we compare theoretical and modern observed data on the eastward drift of the solid inner core. It is shown that the best agreement may be obtained if the turbulent viscosity of the liquid core is about 2 × 10
3
Poise 相似文献
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The nutations of the planets Mars andEarth are investigated and compared. Alarge number of interior structureparameters are involved in the nutationcomputations. The comparison between the observations and the computationsprovides several constraints on these parmeters andtherefore allows a better understanding of the physics of the interior of theplanet. For the Earth, the high precision of the observations of the nutationshas led to a very good determination of interior properties of the planet. ForMars, observations of nutations are not yet available, and we review how theamplitude of the Martian nutations depends on the hypotheses consideredfor its interior. Although Mars is very similar to the Earth, its interior is not well known;for example, we don't knowif its core is liquid or solid. Only if the core is liquid,the Free Core Nutation (FCN) normal mode exists and can alter the nutationswhich are close to the resonance. From the observed geoids, it is known thatboth planets are not in hydrostatic equilibrium. The departure is larger forMars than for the Earth, and consequently, the implication of considering a convective mantle instead of a mantle in hydrostatic equilibrium described byClairaut's equation for the initial equilibrium state of the planet is largeron the Martian nutations than on the Earth nutations. The consequences of theuncertainty in the core dimensions are also examined and shown to be of a veryhigh influence for Mars if the core is liquid, due to the potential changes inthe FCN resonance. The influence of the presence of an inner core, which isknown to exist for the Earth, could be more important for Mars than for theEarth if the inner core is large. Due to the presence of Tharsis on Mars, thetriaxiality of this planet has, additionally, larger effects than on Earth. 相似文献
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The determination of the coefficient of viscosity of eruptive products gives useful elements to the knowledge of possible variations of composition and physical conditions of the magmas. 相似文献
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Studia Geophysica et Geodaetica - 相似文献
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地震激励下处于深水中的桥墩和周围水体的相互作用将对桥梁结构的动力响应产生较大影响。首先对地震作用下水-桥墩的相互作用理论做了概括,给出了动水压力对桥墩的作用效应及各自的适用范围;对主要的三种考虑流固耦合效应的分析方法做了对比,探讨了地震作用下影响水-结构相互作用的主要因素,并对今后的研究提出了建议。 相似文献
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V. E. Pavlov T. Yu. Tolmacheva R. V. Veselovskiy A. V. Latyshev A. M. Fetisova I. V. Bigun 《Izvestiya Physics of the Solid Earth》2017,53(5):702-713
Until recently, the existing data prevented the geophysicists from accurately dating the Bysy-Yuryakh stratum, which outcrops in the middle reach of the Kotuy River, constraining the time of its formation to a wide interval from the end of the Late Cambrian to the beginning of the Silurian. The obtained paleomagnetic data unambiguously correlate the Bysy-Yuryakh stratum to the Nyaian regional stage and constrain its formation, at least a considerable part of it, by the Tremadocian. This result perfectly agrees with the data on the Bysy-Yuryakh conodonts studied in this work and yields a spectacular example of the successful application of paleomagnetic studies in solving important tasks of stratigraphy and, correspondingly, petroleum geology. Within the Bysy-Yuryakh stratum, we revealed a large normal-polarity interval corresponding to the long (>1 Ma) period when the geomagnetic reversals were absent. This result, in combination with the data for the Tremadocian and Middle–Upper Cambrian sequences of the other regions, indicates that (1) the rate of occurrence of the geomagnetic reversals on the eve of the Ordovician Moyero superchron of reversed polarity was at most one reversal per Ma; (2) the superchron does not switch on instantaneously but is preceded by a certain gradual change in the operation conditions of the dynamo mechanism which, inter alia, manifests itself by the reduction of the frequency of geomagnetic reversals with the approach of the superchron. This finding supports the views according to which a process preparing the establishment of the superchrons takes place at the core–mantle boundary. 相似文献
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Geomagnetism and Aeronomy - The magnetic evolution of the active region of the Sun at the level of the photosphere has been studied. Magnetic synoptic maps of the 2007 Kitt Peak Observatory were... 相似文献
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Josef Vykutil 《Studia Geophysica et Geodaetica》1968,12(2):217-220
Резюме Дается вывод формул для вычислений длины хорды, длины и азимутов нормаляных сечений и длины геодезической линии эллипсоида.
Применяются тригонометрические функции данных величин и постоянные принятого ргфгргнц-эллипсоида, что является целесообразным
при использовании вычислителQjных машин, особенно автоматов. Рабочие формулы рекомендуются в форме (8–11).
Dedicated to Professor František Fiala on His 85th Birthday
Address: Veveři 95, Brno. 相似文献
Dedicated to Professor František Fiala on His 85th Birthday
Address: Veveři 95, Brno. 相似文献