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Acta Seismologica Sinica(English Edition) 2003年第1期16卷 34-41页

作者：张赤军方剑马宗晋 InstituteofGeodesyandGeophysics ChineseAcademyofSciences InstituteofGeology ChinaSeismologicalBureau

On the basis of the reality of recent tectonic movement and discarding such a viewpoint that the isostatic adjust-ment only results from excessive or insufficient compensation, we have discussed the tectonic stress causing ine-quality and regarded the isostatic anomaly as a load on the earths interior, thus the earths inner stress can be cal-culated. The research results show that in the East China Sea and its eastern marginal seas the change of the verti-cal stress derived from the isostatic gravity anomaly is more marked than that of the horizontal stress. Along the Ryukyu trench there is an enhancement of vertical stress by 5 MPa, which evidently reflects the effect of plate subduction. On contrary, along the island arc to the northwest of the trench the vertical stress weakens by about 5 MPa. The horizontal stresses in eastern and western parts are obviously different, the east westward stress on the oceanic crust sx is negative (while the pressure is positive) but on the continental crust is positive. These facts indicate the effect of compression between plates.

关键词： isostatic gravity anomaly tectonic stress plate movement

Rules of distribution in a plastic zone of rocks surrounding a roadway affected by tectonic stress

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Mining Science and Technology 2010年第1期20卷 47-52页

作者： LU Yan TU Shihao State Key Laboratory of Coal Resources and Mine Safety Xuzhou 221116 China School of Mining Engineering China University of Mining & Technology Xuzhou 221116 China

In order to study the rules of distribution in a plastic zone of rocks, surrounding a roadway, affected by tectonic stress, we first analyzed the mechanics of a roadway affected by tectonic stress and derived a theoretical formula for the plastic zone of rocks surrounding a roadway. We also analyzed the distribution characteristics of the plastic zone under different levels of tectonic stress, vertical pressure, cohesion and friction angle of the surrounding rock. Secondly, we used numerical simulation to analyze the range and shape features of the plastic zone of rocks surrounding the roadway, given different tectonic stress levels. Finally we used a rock drilling detector to carry out field measurements on the broken state of rock surrounding the roadway at the –700 substation and channels in the Xinzhuang mine of the Shenhuo mining area. Given the measured ground stress, we analyzed the relationship between tectonic stress and the distribution of this plastic zone. Our results show that the range of the plastic zone at the top and bottom of the roadway increases with an increase in tectonic stress and this increase is especially obvious at the roadway corner.

关键词： tectonic stress rock surrounding a roadway plastic zone

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Mining Science and Technology 2010年第5期20卷 718-722页

作者： LU Yan LIU Changyou School of Mines China University of Mining & Technology Xuzhou 221116 China State Key Laboratory of Coal Resources and Mine Safety Xuzhou 221008 China

In order to study the mechanism of bolt support and the behavior of strata in a coal roadway under tectonic stress,deformation and destruction of a roof,floor and sides were studied using an experiment in similarity *** also studied the mechanism and types of bolt support functions in the coal *** results show that with an increase in horizontal tectonic stress,the strata in the roof and floor of the roadway gradually separate and become shear failure *** in side walls moves,but its integrity remains *** bolts are mainly affected by tension and roof bolts by the effect of shear.

关键词： tectonic stress coal roadway bolt support similarity simulation

Study on relation between tectonic stress and coal-mining subsidence with similar material simulation

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Journal of Coal Science & Engineering(China) 2005年第2期11卷 37-40页

作者：夏玉成支剑锋孙学阳 Department of Geological and Environmental Engineering Xi’an University of Science & TechnologyXi’an 710054 China Department of Geological and Environmental Engineering Xi’an University of Science & TechnologyXi’an 710054 ChinaDepartment of Basic Courses Xi’an University of Science & TechnologyXi’an 710054China

Using a minitype and stress-type test device for similar material simulation of coal-mining subsidence, the relation between tectonic stress and coal-mining subsidence was successfully simulated, furthermore, the test period of similar material simulation was obviously shortened and the test process was more dexterous and convenient. To do simi-lar material simulation with the minitype and stress-type test device was feasible and high-efficient. Bringing two models with the same geological and mining conditions to bear lateral compressive stress and tensile stress respectively and simulating the process of underground mining, the test results indicate that: under the compressive stress, the col-lapse of the coal roof occurs belatedly and the damaged range in cover of coal seam is smaller, therefore the movement and deformation of the cover and its damage to the ground geological environment are not evident; whereas under tensile stress, the situation is contrary to which mentioned above. A conclusion was obtained from the test that the ground environment hazards in coal mining areas were controlled by the regional geo-logical tectonic stress field.

关键词： tectonic stress coal-mining subsidence similar material simulation stresstype test device the cover of coal seam

Present-day tectonic stress in the East China Sea region and its possible origin

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Acta Seismologica Sinica(English Edition) 1999年第5期12卷 542-549页

作者：许忠淮徐国庆吴少武 Institute of Geophysics China Seismological Bureau Beijing China Geological Research Institute China Offshore Oil Donghai Corporation Shanghai China Seismological Bureau of Jiangsu Province Nanjing China

This paper analyzes bore-hole wall breakouts of the 5 wells located in southern part of the East China Sea regionwith logging sections deeper than 3 000 m and logging intervals longer than 1 000 m or even near 2 000 m. Bymaking a combined study of the breakout characteristics of these 5 wells and 11 other wells analyzed in Xu andWu (1997). it is inferred that the maximum horizontal principal compressive stress in the East China Sea 'region isgenerally in NE-SW direction, and the horizontal differential stress there is possibly weak. P- and T-axisorientations of focal mechanism of earthquakes occurred from 1977 to 1998 in the region of O kinawa trough andRyukyu Islands are investigated. p-axes of earthquakes in Okinawa trough are generally oriented NE-SW,coinciding with the trough stretching trend. while T-axes are nearly perpendicular to the trend. This indicates thatthe horizontal action of the Philippine Sea Plate to the East China Sea region is not pushing but pulling. A two dimensional finite element simulation is conducted to study the origin of the present-day tectonic stress in the EastChina Sea region. The result shows that the stress there is possibly attributable to both the strong northwestwardcompression in Taiwan region and the back-arc extension of the Ryukyu island arc. Less strong ear thquakes in theEast China Sea region is possibly related to the weak horizontal shear stress there.

关键词： East China Sea tectonic stress bore-bole breakout focal mechanism

The influence of intensity and properties of tectonic stress on the process of coalification

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Journal of Coal Science & Engineering(China) 2012年第2期18卷 158-162页

作者： WANG Zhi-rong JIANG Bo CHEN Ling-xia College of Hydraulic and Environmental Engineering Zhengzhou UniversityZhengzhou 450001China

Through the research on stress metamorphism character of the II1 coal seam in Ludian gliding structure, the stress effecting factors of metamorphism and hydrocarbon generation process of tectonic coal were studied. It is shown that different tectonic stress has different coal evolution effects. Compared with tensional stress, compressive stress, which has apparent anisotropic characteristics, has greater stimulative effect against the increase of coal metamorphic degree, the abscission of functional group and side chains of basic structural unit, and the formation of gas primarily composed of methane.

关键词： tectonic stress gliding structure coal metamorphism and hydrocarbon generation process gas geological hazards

A present-day tectonic stress map for eastern Asia region

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Acta Seismologica Sinica(English Edition) 2001年第5期14卷 524-533页

作者： XU Zhong-huai Institute of Geophysics China Seismological Bureau Beijing China

Based on the data of earthquake centroid moment tensor (CMT) solution, P-wave first motion focal mechanism solution and deep hole breakouts, a present-day tectonic stress map for eastern Asia region is compiled. The original stress data are smoothed for every 200 km × 200 km area by taking the average of all stress indicators within each sub-region. The stress map shows the spatial distribution of the orientation of principal stress axes and the stress regimes. An earthquake focal mechanism map for the eastern Asia is also given. The maps of orientation of principal stress axes show that, apart from the strong influence of the collision between the Indian Ocean plate and Eurasian plate, the present-day tectonic stress in eastern Asia is significantly affected by the back-arc extension of the subduction zones. The joint effect of the continental collision at the Himalaya arc and back-arc extension in the Burma arc region may be responsible for the remarkable rotation of the principal stress orientations in southeastern part of the Tibet plateau. The joint action of the collision between the Philippine Sea plate and Eurasian plate at Taiwan Island and the back-arc extension of the Ryukyu arc affect the stress field in eastern part of China. There are no strong earthquakes in the present day in the vast back-arc region of the Java trench subduction zone. The back-arc extension there may create a condition favorable to the southward flow of the lithosphere material in southeastern Asia. In the inner part of the Tibet plateau region, roughly demarcated by the Kunlun mountain, the northern and northeastern part is a broad intracontinental compressive zone, while the southern and southwestern part is generally in a normal-faulting stress state.

关键词： Eastern Asia stress map tectonic stress

Anisotropic zoning in the upper crust of the Tianshan tectonic Belt

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Science China Earth Sciences 2021年第4期64卷 651-666页

作者： Jin LI Yuan GAO Qiong WANG Earthquake Administration of Xinjiang Uygur Autonomous Region Urumqi 830011China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

The Tianshan tectonic Belt is an intracontinental orogenic belt formed by continental convergence that has undergone long-term tectonic evolution. The reactivation that began during the Cenozoic Period has led to complex structural changes. The goals of this study are to review the seismic observational data obtained during 2009–2019 in the Xinjiang regional seismic network and analyze the anisotropy of the upper crust in the Tianshan area. Therefore, a shear-wave splitting system was adopted to collect and analyze shear-wave splitting parameters of 33 stations in the study area. The anisotropy of the upper crust of the Tianshan is spatially diverse, and the dominant polarization directions of fast shear-wave reflect the spatial variations of regional tectonic stress. In addition, the time delays of slow waves are proportional to the intensities of anisotropy in the upper crustal medium. The dominant polarization direction of the fast waves in the western segment of the North Tianshan Mountain,northwestern corner of the Tarim Basin, and northeastern edge of Pamir is consistent with the tectonic stress fields in the area. In the northern part of the Keping Block, the dominant polarization directions of the fast waves are consistent with the fault trends;however, they are at a high angle to the dominant directions of the regional tectonic stress field indicating that the anisotropy is affected by the faults in the area. The anisotropy of the eastern segment of the South Tianshan Mountains and the surrounding area of Urumqi are affected by the local stress field and fault structure. The polarization directions at some of the stations are subparallel to the directions of the regional principal stress. However, for other stations, the polarization directions are aligned with the neighboring faults. The polarization directions of the fast waves in most of the study area are consistent with the local tectonic stress fields. Thus, stress compression phenomena such as the Ta

关键词： Tianshan tectonic Belt Seismic anisotropy Shear-wave splitting tectonic stress

The Dauki Fault at the Shillong Plateau-Bengal Basin Boundary in Northeastern India:2D Finite Element Modeling

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Journal of Earth Science 2012年第6期23卷 854-863页

作者： Md Shofiqul Islam Ryuichi Shinjo Faculty of Science University of the RyukyusOkinawa 903-0213Japan Department of Petroleum and Mining Engineering Shahjalal University of Science and TechnologySylhet 3114Bangladesh

The Dauki fault is a major fault along the southern boundary of the Shillong plateau that may be a source of destructive seismic hazards for the adjoining areas, including northeastern Bangladesh. In this study, we simulated the present stress distribution and the ongoing convergence deformation within the study area using numerical simulation. This simulation attempts to deter- mine the proper dip angle of the Dauki fault from a variety of differently established models but with the same realistic boundary conditions. The simulated stress field helped to predict the type of tec- tonic environment and the faulting patterns of the study area. The best-fit model can account for the compressive stress regime in the study area, except in the uppermost part of the Shillong plateau, the Bengal basin, and Assam areas where extensional stress regimes exists. In the model, the elements for which Mohr-Coulomb＇s failure occurs correspond with the observed earthquake data that refer to the Dauki fault as a north-dipping thrust fault.

关键词： Dauki fault Bengal basin tectonic stress earthquake.

New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi Li Laboratory of Computational Geodynamics,College of Earth Science,Graduate University of Chinese Academy of Sciences,Beijing 100049,China Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within China and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： tectonically deformed coals Ultrastructure Pore structure tectonic stress Strain environment