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1.
Based on the high-accuracy data obtained from the GPS measurements carried out in 1992, 1995 and 1996, the isochronous active
units with different kinematic property inside the North China area have been distinguished, 4 active units and 1 transition
zone with distinct differential movement have been determined. They are Ordos-Yinshan unit, Yanshan unit, Shanxi-Hebei-Shandong
(Jin-Ji-Lu) unit, Jiaodong-Liaoning-Shandong (Jiao-Liao-Lu) unit and Yanshan-Hebei (Yan-Ji) transition zone. The relative
movements among the neighboring units in this period have been given. 1 The compressive movement between Ordos-Yinshan unit
and Yanshan unit is not obvious with an amount of 0.4±1.3 mm/a. 2 Jin-Ji-Lu unit moves E40°S off the Ordos-Yinshan unit and
the magnitude is 4.4±1.0 mm/a. 3 Relative to the Yan-Ji transition zone of differential movement, Yanshan unit shifts W38°N
with a value of 2.4±1.3 mm/a and Jin-Ji-Lu unit moves eastward 35° by south with an amount of 2.3±0.9 mm/a. 4 Jin-Ji-Lu unit
has a tensional left-lateral movement of 4.7±1.4 mm/a in the direction of E37°S relative to Yanshan unit. 5 Some area near
Tanlu belt which is located in the southern part of Jin-Ji-Lu block has a southward movement 14° by west with a magnitude
of 1.5±1.1 mm/a off the Jin-Ji-Lu unit. 6 Relative to Jin-Ji-Lu unit, Jiao-Liao-Lu unit has a trend of clockwise movement
with a tensional right-lateral motion at the north end which neighbors Yanshan unit and a compressive motion at the south
end. It should be noted that the errors given in the paper are obtained based on the divergence among the displacements of
the sites in the unit, rather than the value calculated from the displacement error of the sites. The analyzed results indicate
that: 1 Shanxi tectonic zone and Yan-Ji transition zone are the major tectonic active zones to show the frame and magnitude
of interior relative movement in North China area, and others are the secondary tectonic active zones; 2 The complete horizontal
deformation in the North China area is not homogeneous nor successive; 3 The kinetic model of North China area might be "mantle
dragging plus boundary coupling".
Foundation item: The National Key Basic Research Project Mechanism and Prediction of Continental Earthquakes (G1998040700). 相似文献
2.
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
3.
华北地震活动中短期异常图像研究 总被引：2，自引：0，他引：2
系统研究了多种地震活动性方法后认为, 1970年以来华北地区发生的MS≥5.8中强震前, 约83%具有3级或4级地震异常条带、 孕震空区及信号震出现。 震前有信号震的比例占92%, 83%的信号震距主震150 km以内, 距主震发生时间小于1年的占67%。 条带时间形成进程在2年内的约占90%, 震前条带形成后到主震发生83%在5个月内。 空区形成进程在1年半内的占83%, 空区形成后到主震发生91%在50天内, 为有意义的地震活动图像短期异常特征。 文中还探讨了异常条带图像的定量判别指标及其与未来强震的关联。 相似文献
4.
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
5.
ＰｒｅｌｉｍｉｎａｒｙｒｅｓｕｌｔｓｏｎｋｉｎｅｍａｔｉｃｍｏｄｅｌｏｆｔｅｃｔｏｎｉｃｂｌｏｃｋｓｄｅｒｉｖｅｄｆｒｏｍｈｉｇｈｐｒｅｃｉｓｉｏｎＧＰＳｏｂｓｅｒｖａｔｉｏｎｓｉｎＳｏｕｔｈｗｅｓｔＣｈｉｎａＬＩＲＥＮＨＵＡＮＧ１）（黄立人）... 相似文献
6.
Based on the horizontal movement velocities and their error estimations of 144GPS stations in North China de-duced from the results obtained from multiple GPS measurements carried out in the period of 1992-2001,the horizontal deformation in the area is stuklied.The movements,entire deformations,local deformations,activeity patterns and intensities along the boundary zones are derived.And then the risk of strong earthquake in the area is estimated.In the research,the horizontal displacement observations can be considered as the sum of three parts.The first part is the entire motion following Eurasian plate,which can be derived from NUVAL-IA model;the second part is the relative motions and deformations between the sub-tectonic blocks in the studied area,which can be derived from a set of displacement observations determined by the expanded QUAD method in the paper;the third part is the local deformations and errors in the sub-tectonic blocks,which can be described as the inhomoge-neous strains of the block.The method and results are introduced in detail in the paper. 相似文献
7.
Introduction The Great North China, located at longitude 106E to 124E and latitude 31N to 42N, in-cludes three secondary active tectonic blocks, Ordos, Yanshan and North China plain (Figure 1). The geological tectonics of these three secondary blocks is much different from each other. As a stable block with high rigidity, the Ordos block is mostly surrounded by down-faulted basins with an inactive interior since Cenozoic, although the fault zones along its boundary are strongly active wi… 相似文献
8.
华北GPS地形变监测网的建立 总被引：4，自引：4，他引：4
全球定位系统GPS是利用监测地壳运动进行地震预测的新手段。华北是一个重要的地震监视区。应用GPS技术在华北布设了一个四维地形变监测网。由于采取了一系列先进的方法和措施,首次观测获得了高精度的成果,为今后大震预测和地球动力学的研究奠定了基础。 相似文献
9.
目前很多文献基于弹性力学假设,以小形变、均匀应变场为前提,利用GPS资料建立了中国大陆块体的整体旋转与均匀应变模型,并对模型进行了相关检验.但上述对模型的检验侧重从模型的拟合效果上进行分析和比较,忽略了对模型的适用性和假设条件合理性的检验.实际上,不同块体由于自身构造和外部条件的不同,其运动状况与应变状态并不完全一致,模型的适用性需进一步的验证.本文提出了两步检验方法对所建立的模型在中国大陆6个主要块体上进行了检验：第一步对应变参数进行显著性检验,第二步对应变均匀性进行检验,结果表明：根据所用数据精度,华南块体的刚性程度在95% 的置信水平上可以认为显著的,建立模型时不必考虑内部形变;其他块体内部形变显著,整体旋转与均匀应变模型并不能反映真实的地壳运动状态,必须考虑其形变的不均匀性. 相似文献
10.
Li Yanxing Shen Jianhua and Wang MinFirst Crustal Deformation Monitoring Center SSB Tianjin ChinaDepartment of Scientific Programming Earthquake Monitoring SSB. Beijing China 《中国地震研究》1995,(3)
The Global Positioning System (GPS) is a new method to monitor the crustal deformation for earthquake prediction.Now a four-dimensional crustal deformation monitoring network applying GPS techniques has been established in North China,which is an important seismic monitoring area.Results with high precision have been achieved in the first measurement since a series of advanced methods and measures were adopted,and thus a good foundation has been laid for future researches on earthquake prediction and geodynamics. 相似文献
11.
虽然InSAR技术具有高精度、大范围和高空间分辨率等优点,但只能监测雷达视线方向上的一维地表形变;而GPS技术虽可以监测地表的三维形变,但其空间分辨率很低.本文针对融合InSAR和GPS技术监测地表高空间分辨率三维形变展开研究.首先证明了简单的局部最优化迭代算法就能求得综合InSAR和GPS监测地表形变速率的能量函数模型的全局最优估值.随后提出了利用BFGS局部最优算法反演最优的地表三维形变速率.该方法既能避免全局最优化算法计算复杂且难以收敛的问题,又能克服传统的解析法中数值计算不稳定的缺点.最后,通过模拟实验和美国南加州真实数据实验表明,该方法能够得到高精度的地表三维形变速率场.而且当观测或插值误差导致解析法误差较大时,BFGS方法仍能得到高精度、稳定的全局最优解. 相似文献
12.
On the Consistency of Large Earthquake Moment and Strain Rate Inferred from GPS Data in North China 总被引：2，自引：0，他引：2
Wan Yongge 《中国地震研究》2005,19(3):249-258
INTRODUCTIONStudyingthe relation between the accumulation of crustal strain and the release rate of seismicmoment is animportant subject of earth science research.It is also one of the important methods ofestimatingthe future seismic risk(Ward,1994;1998a;… 相似文献
13.
华北地区大地震矩释放率和GPS应变率的一致性研究 总被引：2，自引：0，他引：2
GPS测量技术可以在较大地区范围内获得高精度地壳形变速率。稳定的应变速率提供了精确确定地震活动率的机会。本文运用Kostrov(1974)的公式将经平滑的华北地区应变速率转化为矩释放率，并与运用1303年洪洞地震以来的地震目录计算的矩释放率进行比较，发现两者之比南北向为60．6％，东西向为68．9％，北东剪切分量为104．1％。近似为1的比率表明了GPS测量结果的可靠性。这个结果对结合历史地震及大地形变测量估计矩释放进行地震危险性评估具有一定参考意义。 相似文献
14.
Vladimir Schenk Zdeňka Schenkova Zuzana Jechumtálová 《Studia Geophysica et Geodaetica》2009,53(3):329-341
In West Bohemia in the period of 2003–2005 five permanent GPS stations were established to detect local movement trends. Their
mutual position changes were determined from time series of GPS observations and were associated with seismic, gravity, and
geo-scientific data related to the geodynamics of the West Bohemian region. Knowledge of local physical processes based on
spatial and time earthquake occurrences, focal mechanisms of main events, stress and strain fields set up a tool for recent
seismotectonic analyses. The permanent GPS measurements bring independent effective phenomenon, direct monitoring of site
movements. The movements detected by our GPS stations evidenced WSW-ENE extension with subsiding trends in the western part
of the Cheb Basin and the Smrčiny Mts. Besides, there were monitored dextral movements along the Mariánské Lázně tectonic
fault zone (MLF). A comparison of results with previous data formed a presumption that an antithetic stress pattern has to
exist inside the inner part of the MLF tectonic zone. This antithetic stress can explain the coexistence of dextral and sinistral
movements on individual tectonic elements in the West Bohemian area. 相似文献
15.
基于GPS的华北地区地壳水平形变特征研究 总被引：1，自引：0，他引：1
利用中国大陆构造环境监测网络2009、2011年2期的GPS数据资料,计算得到华北地区相对于稳定的欧亚板块的区域水平速度场。根据水平速度场,基于连续变形假说,采用三角形方法计算了区域应变场特征值,并用GMT绘制了其分布图像。结合地震地质资料对该区的地壳水平形变特征进行分析研究,得出了有意义的结论:(1)水平相对运动与应变率场分布显示,板块交界处的断裂带及其附近区域地壳运动差异显著,应变率量值较为突出;(2)山西断陷带的活动方式与地质结果具有差异性;(3)区内最大剪应变、面膨胀的高值区主要位于环渤海的京津唐地区、山西断陷带中南部及郯庐断裂带中南段。 相似文献
16.
基于地磁坐标和地理位置的关系,利用Newton迭代法推导了地磁北极的计算公式;根据Klobuchar模型中电离层电子含量与地磁位置的关系,给出地磁位置的表达式;进而建立了GPS观测量估计地磁北极的模型.理论分析和数据验证了方法的可行性,得出1)Klobuchar模型属于全球性的电离层估计模型,对于区域性电离层信息描述的不十分准确,建立区域化Klobuchar模型将更有利于地磁北极的估计;2)利用泰勒公式将Klobuchar模型线性化的过程中,公式仅取其一阶项,将会影响模型的精度,有待于提高模型的展开阶数;3)实际中地磁北极的估计结果受初始值得约束;4)不同计算方法和模型对结果的可靠性有所影响,试图选择其它估计过程和方法,提高估计的可靠性. 相似文献
17.
Lu XiaoFei Tan Kai Li Qi Li Chengtao Wang Dongzhen Zhang Caihong 《Journal of Seismology》2021,25(6):1525-1535
Journal of Seismology - To study the seismicity of the Red River fault, observational GPS data from the Crustal Motion Observation Network in China from 1999 to 2018 were selected to calculate the... 相似文献
18.
Introduction To correctly understand the tectonic deformation of continental lithosphere, its dynamical mechanics and seismic activity, we should firstly acquire the velocity field and strain field of lithospheric tectonic motion with fine resolution and consistent accuracy (Molnar and Lyon-Caen, 1989; Molnar, 1990). And the quality, distribution and density of observed data are the basis for studying crustal tectonic deformation. In the past, crustal deformation is usually determined indi-r… 相似文献
19.
20.
太阳活动与华北强震关系的分析 总被引：10，自引：2，他引：8
统计了太阳黑子活动11年周期和22年周期与华北地区(E108°～124°,N34°～42°)1815年～2002年187年6级以上强震的关系。结果显示,它们之间存在着较好的对应关系,华北地区的强震自1815年第4高潮以来,有84.6%的强震集中在太阳黑子11年变化周期的峰年段(±1年)和谷年段(±1年)内发生;其中尤以双周峰年段、单周谷年段较为集中;而单周下降时段却从未有过强震发生。目前正处于太阳黑子活动第23周单周峰年之后的下降时段,该统计区内强震发生的概率极低。 相似文献