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魏娜  施闯  耿长江  刘经南 《大地测量与地球动力学》2010,30(4):109-112

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Fault plane parameters of Tancheng M8? earthquake on the basis of present-day seismological data          下载免费PDF全文

Cuiying Zhou  Guiling Diao  Jie Geng  Yonghong Li  Ping Xu  Xinliang Hu  Xiangdong Feng 《地震科学（英文版）》2010,23(6):567-576

The great Tancheng earthquake of M8? occurred in 1668 was the largest seismic event ever recorded in history in eastern China. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We relocated those earthquakes with the double-difference method and found focal mechanism solutions using gird test method. The inversion results are as follows: the strike is 21.6°, the dip angle is 89.5°, the slip angle is 170°, the fault length is about 160 km, the lower-boundary depth is about 32 km and the buried depth of upper boundary is about 4 km. This shows that the seismic fault is a NNE-trending upright right-lateral strike-slip fault and has cut through the crust. Moreover, the surface seismic fault, intensity distribution of the earthquake, earthquake-depth distribution and seismic-wave velocity profile in the focal area all verified our study result.

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祁连山构造带的新构造变形机制   总被引：1，自引：0，他引：1  

侯康明  张忻  刘小龙 《华南地震》1999,(2)

论述了祁连山构造带新生代以来的变形过程及形成机制。研究表明： 祁连山构造带的变形过程是在欧亚大陆与印度大陆碰撞汇聚作用下发生和发展的, 其变形过程与整个青藏高原的隆升过程同步进行。其中阿尔金断裂在其东段的走滑贯通对祁连山－ 河西走廊地区的构造运动影响很大。上新世末或第四纪初阿尔金断裂东段的走滑导致了祁连山地区应力场的旋转, 进而增大了沿 Ｎ Ｗ Ｗ 向主断裂的水平走滑分量。它是引起主断裂发生走滑的重要原因之一。  相似文献   

由地下水位变化反演大同—阳高6.1级地震前后应力场的动态图像     

张昭栋  王吉易  耿杰  魏焕 《内陆地震》1999,(2)

分析研究了承压含水层应力应变与井水位变化之间的定量关系,得出了井水位变化与含水层应力应变之间的定量关系公式,给出了利用承压井水位变化反演含水层应力变化的两种新方法。利用大同地震前后井水位变化资料,反演了该地震前后大区域应力场的动态调整变化,并形成了时间与空间的演化图像。利用这些图像分析了大同地震前后大区域应力场的动态调整变化特征与可能的机制。  相似文献   

Precise Multibeam Acoustic Bathymetry   总被引：7，自引：0，他引：7  

Xueyi Geng  Adam Zielinski 《Marine Geodesy》1999,22(3):157-167

The maximum error in ocean depth measurement as specified by the International Hydrographic Organization is 1% for depth greater than 30m. Current acoustic multibeam bathymetric systems used for depth measurement are subject to errors from various sources which may significantly exceed this limit. The lack of sound speed profiles may be one significant source of error. Because of the limited ability of sound speed profile measurement, depth values are usually estimated using an assumed profile. If actual sound speed profiles are known, depth estimate errors can be corrected using ray-tracing methods. For depth measurements, the calculation of the location at which a sound pulse impinges on the sea bottom varies with the variation of the sound speed profile. We demonstrate that this location is almost unchanged for a family of sound speed profiles with the same surface value and the same area under them. Based on this observation, we can construct a simple constant-gradient equivalent sound speed profile to correct errors. Compared with ray-tracing methods, the equivalent sound speed profile method is more efficient. If a vertical depth is known (or independently measured), then depth correction for a multibeam system can be accomplished without knowledge of the actual sound speed profile. This leads to a new type of precise acoustic multibeam bathymetric system.  相似文献   

利用MICAPS操作平台建立相似预报系统制作三峡库区面雨量预报     

周国兵  李梗  王中 《高原山地气象研究》1999,9(3)

本系统是在借助MICAPS操作平台的基础上,利用相似预报原理和统计预报方法建立起来的三峡库区范围内面雨量预报系统,并利用欧洲中心数值预报制作逐日滚动预报.  相似文献   

利用MICAPS操作平台建立相似预报系统制作三峡库区面雨量预报   总被引：2，自引：0，他引：2  

周国兵  李梗 《四川气象》1999,9(3):27-28

本系统是在借助ＭＩＣＡＰＳ操作平台的基础上,利用相似预报原理和统计预报方法建立起来的三峡库区范围内面雨量预报系统,并利用欧洲中心数值预报制作逐日滚动预报  相似文献   

vlisp地块自动分割算法在土地确权中的应用研究     

葛俊涛  高彦涛  贾复生  耿艳辉 《地理空间信息》2022,20(4):74-76,99

农村土地承包经营权确权颁证登记工作外业结束后,绘制地块及其属性工作是内业数据处理的繁琐任务之一,承包地块及其属性信息绘制具有大批量、同步骤等特性,针对这种情况,利用vlisp开发CAD插件,用于农经权批量绘制地块及权属信息赋值,结果表明自动分割插件在农经权工作中提高了效率,节省了大量的人力、物力,在地块勾绘、承包方姓名...  相似文献   

塔克拉玛干沙漠地表潜热时空特征分析   总被引：6，自引：4，他引：2  

王敏仲  魏文寿  杨莲梅  何清  耿燕 《中国沙漠》2008,28(5):940-947

利用1979年3月至2004年2月月平均的NCEP/DOE再分析地表潜热资料,在分析塔克拉玛干沙漠四季潜热基本气候特征的基础上,通过EOF方法,对沙漠地表潜热异常变化的空间结构和时间演变趋势作了诊断研究。结果表明：①沙漠地区夏季潜热最大,春季和秋季次之,冬季最小;靠近山区的沙漠西部、西北部地区四季明显大于中、东部地区。②根据四季地表潜热距平场的EOF分析,该区潜热异常主要有全区一致型、南北差异型以及西北—东南差异型三种常见的分布模态。③25 a期间,塔克拉玛干沙漠地表潜热在第一空间尺度上四季都有不同程度增强的趋势;在第二空间尺度上,春季沙漠北部、西北部有减弱的趋势,南部、东南部有增强的趋势,而冬、夏、秋季变化趋势不是很大。  相似文献   

Characteristics and Mechanisms of Co-seismic Groundwater Responses in Tayuan Well     

Sun Xiaolong  Liu Yaowei 《中国地震研究》2009,23(2):180-191

Co-seismic responses of the groundwater level and temperature in the Tayuan well of 68 earthquakes (M_S≥7.0) from January 2004 to September 2007 were analyzed. Results show that the Tayuan well has a strong ability to record large earthquakes worldwide, and the co-seismic response shows a pattern of water level oscillation → temperature decrease→ oscillation stop → temperature resumption. Further analyses indicate that the amplitude of the water level and temperature change is not only concerned with the epicenter distance and magnitude, but is also related to the temporal state of aquifer while the seismic wave arrives. Mechanisms of water level oscillation, temperature decrease, water level oscillation stop and temperature resumption are discussed, with the results from previous research on the co-seismic response mechanisms analyzed. These include gas escape, heat diffusion and cold water seepage. Results show that a single mechanism could not explain the co-seismic response of the Tayuan well water level to multiple earthquakes; the results were garnered from a variety of jointly acting mechanisms.  相似文献