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IntroductionSituated in the southeastern part of Eurasia Plate and surrounded by the India Plate, Eurasia Plate, Pacific Plate and Philippine Sea Plate, Chinese mainland especially the area of Qinghai-Xizang (Qingzang) Plateau and the south-north tectonic zone is the area with the most intensive neotectonic deformation. The main component of tectonic activity in Chinese mainland is active blocks. Therefore, it is quite important to study active blocks in the research of tectonic activit… 相似文献
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A preliminary research establishing the present-time intraplate blocks movement model on the Chinese mainland based on GPS data 总被引：4，自引：0，他引：4
Shuo-Yu Zhou Yue-Gang Zhang Guo-Yu Ding Yun Wu Xiao-Jun Qin Shun-Ying Shi Qi Wang Xin-Zhao You Xue-Jun Qiao Ping Shuai Gan-Jin Deng 《地震学报(英文版)》1998,11(4):403-412
The Chinese mainland is regarded as the best area for studying the continental crustal movement and dynamics. In the past,
based on the ground surface observation, it was very difficult to study the movement of the intraplate blocks within a range
of larger space and a time scale of several years quantitatively. In this paper, a method of calculating the Euler vectors
of present-time motion among blocks by using Cardan angles has been given completely based on two periods of GPS repetition
measurement data of the National Ascending Plan of China (NAPC) — the study and application of current crustal movement and
geodynamics in 1994 and 1996. A present-time blocks movement model on the Chinese mainland (PBMC-1), which describes the motion
of seven blocks—Tibet, Chuan-Dian, Gan-Qing, Xinjiang, South China, North China and Heilongjiang block, is established preliminarily.
The velocity field of the relative motion among the intraplate blocks and boundary motion in the Chinese mainland are firstly
given within several years time scale. It is shown by the results calculated with the model that the velocity-rate of each
block is reduced gradually from the south to north and from the west to east, and the motion direction changes gradually from
NNE to E, even SEE or SE. The collision of Indian plate plays a leading role in the movement of the intraplate blocks in the
Chinese mainland, while the motion manner and velocity-rate of block boundary zone (fracture zone) depend on the motion of
every block again. The present-time motion of a time scale of several years computed with the model is not only largely consistent
with the average motion of a time scale of several million years derived from geology, but also very coincident with the results
of geophysical and astronomic observation. It is shown preliminarily that the observed results of space geodesy techniques
such as GPS etc. are capable of discovering the crustal movement at present.
This study is supported by the National Natural Science Foundation of China (NNSFC), National Ascending Plan of China (NAPC)
and Chinese Joint Seismological Science Foundation (CJSSF). 相似文献
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湘东地区(湖南省东部地区)地处华南褶皱系内,经历了多次构造运动,地层普遍褶皱,并伴有一系列NNE—NE向断裂,沿这些断裂形成一些断陷盆地;新构造运动期间,地壳运动以大面积整体性缓慢抬升为主要形式,差异性构造活动较弱,但该区发生了多次中强地震,断裂在第四纪早、中期有活动可能与中强地震的发生有关。文中在收集、分析研究区及附近地区前人工作成果的基础上,对常德-益阳-长沙断裂东南段、湘潭-邵东断裂东北段和永州-衡阳断裂开展了地质学、地貌学的野外考察,综合分析了这些断裂第四纪早、中更新世以来的活动性。采用"地震重复"和"构造类比"2条基本原则,依据特定地段的地质、地震和地球物理场等资料,认为这些断裂带不但具有中更新世活动形迹,而且沿带存在中强地震的潜在危险。综合社会和经济发展的需求等因素,将湘潭—湘乡、邵东、衡山—衡阳、永州等地带划分为新的潜在震源区 相似文献
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以柴达木盆地新构造运动发生的期次、黄河兰州谷地出现的突出构造事件、阿尔金断裂带第四纪所经历的大运动阶段、攀西裂谷区新构造运动分期、北京地区南段新构造运动波动、全国一些地区断裂活动时序等为例证,再次证明了第四纪以来中国大陆地壳活动具有明显的时段性,４次强烈的构造活动分别发生在上新世末至早更新世初、早更新世中晚期、中更新世中晚期和全新世。其中,以中更新世中晚期地壳活动强度最大、波及范围最广 相似文献
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中国大陆现今实测地应力场的状态与板块构造环境、活动断裂带分布、地形地貌以及地壳结构呈现一定相关性. 在中国大陆西缘,印度洋板块与欧亚板块陆发生陆碰撞,在中国大陆东缘,菲律宾海板块、太平洋板块俯冲到欧亚板块之下. 中国大陆内部被大型活动断裂带分割为多个块体,各个块体的地壳结构和厚度呈不均匀分布,地形地貌起伏具有很大的差异. 笔者以中国大陆块体模型为基础,把板块构造作用和重力势作为主要影响地应力状态的两个主要要素,在现今活动构造、GPS和实测地应力等成果的约束下,利用线性黏弹体球壳有限元模拟分析了中国大陆现今地应力场的分布特征和控制因素. 结果表明: (1)构造应力场总体上呈现出西部挤压,东部拉张的特征,印度板块与欧亚板块的持续碰撞形成了青藏高原及其周缘的挤压性质的构造应力场,而东部菲律宾板块与太平洋板块的俯冲形成了黄海、东海和环渤海区域的拉张性质的构造应力场,中间为拉张环境和挤压环境的过渡,最大主应力的方向受到板块构造环境和活动构造分布的控制;(2)重力的影响主要体现在地形梯度大和地壳厚度结构变化大的地壳浅部区域,在藏南、滇西北局部地区的地壳浅部由于受到重力势控制,呈现为张性应力场,在塔里木地区由于重力势引起的应力场与构造应力场同为挤压性质,因此该区的挤压强度得以增加;(3)中国大陆浅部地应力场的状态主要受到区域板块构造环境、块体边界活动构造带的展布和地形的控制,总体上以南北构造带为界,西部以较强的压性构造环境为主,东部为较弱的压性构造环境,藏南和滇西北局部地区存在有张性构造环境;构造应力对地应力的贡献比重随着深度增加而增加;(4)采用黏弹性模型的构造应力场模拟结果比完全弹性模型的模拟结果能够更好地与实测地应力场相吻合,利用完全弹性模型分析由地震等诱发的地应力瞬时变化是有效的;(5)青藏高原东南缘最大主应力方向发生了较大的偏转,其主要控制因素有:印度板块持续的碰撞、中下地壳对上地壳拖曳以及印度板块通过实皆断裂对欧亚板块的剪切拉伸作用. 中国大陆现今地应力场是整个地壳岩石黏弹特性长期演化和断裂活动的结果,是地应力场动态演化过程中在现今时间点上的状态,受到板块构造环境、大陆内部活动断裂分布、地形地貌和地壳结构等因素不同程度的控制,模拟结果为中国大陆地应力场提供了一个定量的参考模型. 相似文献
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青藏高原湖泊涨缩的新构造运动意义 总被引：2，自引：0，他引：2
青藏高原位于我国的西南部,平均海拔4000—5000m。第四纪以来强烈的新构造运动,引起地壳大幅度的隆起,迫使湖泊出现了大规模的退缩及迁移。新的湖泊不断产生或扩大,古老的湖泊又不断消亡或缩小,形成了湖泊变化与构造活动周期的对应性。本文在分析了青藏高原的地貌、第四纪地质,特别是活断层及地震活动性研究的基础上,对于高原≥4km~2的367个湖泊进行了卫片解译,并取得了较好的效果。 相似文献
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The definition of active block is given from the angles of crustal deformation and strain. The movement and strain parameters of active blocks are estimated according to the unified velocity field composed of the velocities at 1598 GPS stations obtained from GPS measurements carried out in the past years in the Chinese mainland and the surrounding areas. The movement and strain conditions of the blocks are analyzed. The active blocks in the Chinese mainland have a consistent E-trending movement component, but its N and S components are not consistent. The blocks in the western part have a consistent N-trending movement and the blocks in the eastern part have a consistent S-trending movement. In the area to the east of 90°E, that is the area from Himalayas block towards NE, the movement direction of the blocks rotates clockwisely and the movement rates of the blocks are different. Generally, the movement rate is large in the west and south and small in the east and north with a difference of 3 to 4 times between the rates in the west and east. The distributions of principal compressive strain directions of the blocks are also different. The principal strain of the blocks located to the west of 90oE is basically in the SN direction, the principal compressive strain of the blocks in the northeastern part of Qingzang plateau is roughly in the NE direction and the direction of principal compressive strain of the blocks in the southeastern part of Qingzang plateau rounds clockwisely the east end of Himalayas structure. In addition, the principal strain and shear strain rates of the blocks are also different. The Himalayas and Tianshan blocks have the largest principal compressive strain and the maximum shear strain rate. Then, Lhasa, Qiangtang, Southwest Yunnan (SW Yunnan), Qilian and Sichuan-Yunan (Chuan-Dian) blocks followed. The strain rate of the blocks in the eastern part is smaller. The estimation based on the stain condition indicates that Himalayas block is still the area with the most intensive tectonic activity and it shortens in the NS direction at the rate of 15.2±1.5 mm/a. Tianshan block ranks the second and it shortens in the NS direction at the rate of 10.1±0.9 mm/a. At present, the two blocks are still uprising. It can be seen from superficial strain that the Chinese mainland is predominated by superficial expansion. Almost the total area in the eastern part of the Chinese mainland is expanded, while in the western part, the superficial compression and expansion are alternatively distributed from the south to the north. In the Chinese mainland, most EW-trending or proximate EW-trending faults have the left-lateral or left-lateral strike-slip relative movements along both sides, and most NS-trending faults have the right-lateral or right-lateral strike-slip relative movements along both sides. According to the data from GPS measurements the left-lateral strike-slip rate is 4.8±1.3 mm/a in the central part of Altun fault and 9.8±2.2 mm/a on Xianshuihe fault. The movement of the fault along the block boundary has provided the condition for block movement, so the movements of the block and its boundary are consistent, but the movement levels of the blocks are different. The statistic results indicate that the relative movement between most blocks is quite significant, which proves that active blocks exist. Himalayas, Tianshan, Qiangtang and SW Yunnan blocks have the most intensive movement; China-Mongolia, China-Korea (China-Korea), Alxa and South China blocks are rather stable. The mutual action of India, Pacific and Philippine Sea plates versus Eurasia plate is the principal driving force to the block movement in the Chinese mainland. Under the NNE-trending intensive press from India plate, the crustal matter of Qingzang plateau moves to the NNE and NE directions, then is hindered by the blocks located in the northern, northeastern and eastern parts. The crustal matter moves towards the Indian Ocean by the southeastern part of the plateau. 相似文献
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大地形变测量所反映的天山最新构造运动 总被引：12，自引：2，他引：12
新疆的新构造运动强烈,各大山系主体显示了断块抬升运动,而两大盆地则表现为相对下沉。分布在山系与盆地交接部位的大型活动断裂和强烈的地震活动有密切的联系。为了解新疆地壳形变的面貌,我们利用50年代至今30多年的精密水准测量资料,绘制了新疆垂直形变速率等值线图。图中清晰地反映了最新构造运动的形态,以及与地质构造的关系。南、北天山交汇的部位是北西向构造带与东西向构造带的汇合部,也是垂直形变速率等值线密度最大的地段。高速隆起与下降相伴生,今后10年内这里是大地震的潜在危险区。 相似文献
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中国西部的青藏和新疆地区现代构造变形活动非常强烈, 业已证实该区可以进一步划分为塔里木、 阿拉善、 天山、 柴达木和西藏5个活动地块。 利用GPS观测资料得到的中国大陆地壳水平运动的速度场, 借鉴全球板块运动模型的建模方法, 将其视为刚性的地块系统, 反演得到各地块相对欧亚板块运动的欧拉矢量, 进而求得各地块两两之间相对运动的欧拉矢量, 并计算出沿地块边界的相对运动速率。 结果显示, 与地块边界上的地震滑移矢量, 由地质学资料得到的滑移速率, 以及GPS数据本身均有较好的一致性, 从而也说明了将该地区划分为若干活动地块并视为刚性地块的合理性。 相似文献
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本文对泉州市区域地壳结构、地质构造、构造应力场和地震活动性进行了综合分析。结果表明,泉州市在第四纪中更新世之前位于环太平洋中、新生代构造一岩浆活动带中,地壳运动频繁而又强烈,地质构造复杂;现代处于菲律宾海板块对欧亚板块挤压形成的“台湾动力触角”影响区,但区内的断裂不具全新世活动性,新构造运动不强烈,有史以来未见≥5．0级地震记载,属于地壳相对稳定区,未来遭遇6．0级地震的危险性不大,其地震破坏性影响主要来自周边孕震区,特别是东部海域,与“台湾动力触角”的作用和滨海断裂带的活动有关。 相似文献
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In this paper, data obtained by the 1995, 1996 and 1999 three GPS campaigns in North China have been used to study intraplate tectonic block movements in this area (N36°–N42°, and E112°–E120°). By a Bayesian inversion method, negative dislocation distributions on three main fault zones and individual relative movements between four intraplate tectonic blocks have been obtained based on these GPS data. The results show that the relative movements between four intraplate tectonic plates are several millimeters per year. The obtained negative dislocation values on the Front Tai-Hong Mountain fault are −5±2 mm/a in tensile component, and 2±2 mm/a in both strike and dip component, which indicates that this fault mainly suffers pull apart tectonic movements. On the Tangshan–Ninghe fault, the obtained negative dislocation values are −3±3 mm/a in dip, −2±2 mm/a in tensile and −1±3 mm/a in strike, which indicates that the east part of this fault still undergoes upward movement. On the Zhangjiako–Beipiao fault, the obtained negative dislocation values are −4±2 mm/a in strike, 0±2 mm/a in dip, and 1±2 mm/a in tensile, which indicates that this fault has sinistral strike movement. According to the inversion results, the southern part of the Zhangjiako-Beipiao fault suffers pull tectonic movements caused by recent upward movement of the eastern part. The pulling tectonic movements are almost totally blocked on the Front Tai-Hong Mountain fault and this fault is more likely to be a potential earthquake source. 相似文献
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Yanxing Li Guohua Yang Zhi Li Liangqian Guo Cheng Huang Wenyao Zhu Yang Fu Qi Wang Zaisen Jiang Min Wang 《中国科学D辑(英文版)》2003,46(2):82-117
The definition of active block is given from the angles of crustal deformation and strain. The movement and strain parameters of active blocks are estimated according to the unified velocity field composed of the velocities at 1598 GPS stations obtained from GPS measurements carried out in the past years in the Chinese mainland and the surrounding areas. The movement and strain conditions of the blocks are analyzed. The active blocks in the Chinese mainland have a consistent E-trending movement component, but its N and S components are not consistent. The blocks in the western part have a consistent N-trending movement and the blocks in the eastern part have a consistent S-trending movement. In the area to the east of 90°E, that is the area from Himalayas block towards NE, the movement direction of the blocks rotates clockwisely and the movement rates of the blocks are different. Generally, the movement rate is large in the west and south and small in the east and north with a difference of 3 to 4 times between the rates in the west and east. The distributions of principal compressive strain directions of the blocks are also different. The principal strain of the blocks located to the west of 90°E is basically in the SN direction, the principal compressive strain of the blocks in the northeastern part of Qingzang plateau is roughly in the NE direction and the direction of principal compressive strain of the blocks in the southeastern part of Qingzang plateau rounds clockwisely the east end of Himalayas structure. In addition, the principal strain and shear strain rates of the blocks are also different. The Himalayas and Tianshan blocks have the largest principal compressive strain and the maximum shear strain rate. Then, Lhasa, Qiangtang, Southwest Yunnan (SW Yunnan), Qilian and Sichuan-Yunan (Chuan-Dian) blocks followed. The strain rate of the blocks in the eastern part is smaller. The estimation based on the stain condition indicates that Himalayas block is still the area with the most intensive tectonic activity and it shortens in the NS direction at the rate of 15.2 ± 1.5 mm/a. Tianshan block ranks the second and it shortens in the NS direction at the rate of 10.1 ± 0.9 mm/a. At present, the two blocks are still uprising. It can be seen from superficial strain that the Chinese mainland is predominated by superficial expansion. Almost the total area in the eastern part of the Chinese mainland is expanded, while in the western part, the superficial compression and expansion are alternatively distributed from the south to the north. In the Chinese mainland, most EW-trending or proximate EW-trending faults have the left-lateral or left-lateral strike-slip relative movements along both sides, and most NS-trending faults have the right-lateral or right-lateral strike-slip relative movements along both sides. According to the data from GPS measurements the left-lateral strike-slip rate is 4.8 ± 1.3 mm/a in the central part of Altun fault and 9.8 ± 2.2 mm/a on Xianshuihe fault. The movement of the fault along the block boundary has provided the condition for block movement, so the movements of the block and its boundary are consistent, but the movement levels of the blocks are different. The statistic results indicate that the relative movement between most blocks is quite significant, which proves that active blocks exist. Himalayas, Tianshan, Qiangtang and SW Yunnan blocks have the most intensive movement; China-Mongolia, China-Korea (China-Korea), Alxa and South China blocks are rather stable. The mutual action of India, Pacific and Philippine Sea plates versus Eurasia plate is the principal driving force to the block movement in the Chinese mainland. Under the NNE-trending intensive press from India plate, the crustal matter of Qingzang plateau moves to the NNE and NE directions, then is hindered by the blocks located in the northern, northeastern and eastern parts. The crustal matter moves towards the Indian Ocean by the southeastern part of the plateau. 相似文献
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利用川滇地区1998～2002年间200多GPS点位的多期复测结果, 将川滇地区分为9个次级活动块体, 计算了各个活动块体的欧拉旋转矢量和主要活动断裂的运动速度, 并分析了该地区的应变场特征. 结果表明, 川滇地区的地壳运动速度具有北强南弱、西强东弱、以菱形块体为主顺时针旋转的特征; 菱形块体外各个块体运动速度大幅衰减; 与地质结果的差异表明, 川滇菱形块体的现今地壳运动由北往南逐渐增强; 青藏高原物质的侧东向挤出在滇中块体南部明显下降, 而丽江—小金河断裂带的吸收作用并不明显; 川滇地区以压应变为主,四川石棉和云南新平一带出现的应变集中地区也许具有发生中强地震的可能性. 相似文献
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本文利用板块几何学的方法研究中国及邻区地块间的相对运动,用数值方法计算了地块运动的角速度及边界断层的滑动速率。计算结果与活断层数据相当吻合,本文还利用地块运动速度讨论了我国现代构造活动 相似文献
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珠江三角洲地区新构造运动 总被引：15，自引：1，他引：15
概述了珠江三角洲地区新构造运动的基本特征：晚第三纪以来的构造运动经历了由强逐渐减弱，晚更新世（约50－30Ka B.P)又重新增强的演变。重点估算了晚第四纪珠江三角洲断块垂直构造运动速率，定量分析了分割断块的断裂构造的活动性。认为斗门断块区和广州－番禺断块区这两个次级断块构造以及围限它们的广州－从化断裂，三水－罗浮断裂，西江断裂，白坭－沙湾断裂的活动性相对较强。从区域地震构造而言 ，珠江三角洲新构造运动远弱于日本－琉球－台湾岛弧，也弱于奥东潮汕和桂东南灵山等强震危险区。但由于其震源浅及松软土层较厚，加上本区经济发达，人口稠密，因此地震造成的破坏和损失仍不可低估，必须加强抗震减灾工作。 相似文献