Seismogenic potential and earthquake hazard assessment in the Tell Atlas of Algeria   总被引：1，自引：0，他引：1  

A. Aoudia  F. Vaccari  P. Suhadolc  M. Meghraoui 《Journal of Seismology》2000,4(1):79-98

Seismotectonic zonation studies in the Tell Atlas of Algeria, a branch of the Africa-Eurasia plate boundary, provide a valuable input for deterministic seismic hazard calculations. We delineate a number of seismogenic zones from causal relationships established between geological structures and earthquakes and compile a working seismic catalogue mainly from readily available sources. To this catalogue, for a most rational and best-justified hazard analysis, we add estimates of earthquake size translated from active faulting characteristics. We assess the regional seismic hazard using a deterministic procedure based on the computation of complete synthetic seismograms (up to 1 Hz) by the modal summation technique. As a result, we generate seismic hazard maps of maximum velocity, maximum displacement, and design ground acceleration that blend information from geology, historical seismicity and observational seismology, leading to better estimates of the earthquake hazard throughout northern Algeria. Our analysis and the resulting maps illustrate how different the estimate of seismic hazard is based primarily on combined geologic and seismological data with respect to the one for which only information from earthquake catalogues has been used.  相似文献   

STAGES OF THE NEOTECTONIC MOVEMENT IN THE MENYUAN BASIN, QINGHAI PROVINCE     

Ma Baoqi 《地学前缘》2000,(Z1)

STAGES OF THE NEOTECTONIC MOVEMENT IN THE MENYUAN BASIN, QINGHAI PROVINCE  相似文献   

Character of active faulting in the North Aegean Sea     

Ruhi Saat&#x;lar  Semih Ergintav  Emin Demirba  Sedat nan 《Marine Geology》1999,160(3-4):339-353

A re-evaluation of the reprocessed seismic reflection data was made for the investigation of the presumed western continuation of the North Anatolian Fault (NAF) in the Aegean and mapping geometries of active faults in the Aegean Sea. Seismic data collected and processed by various national and international companies were selected from the data archives and they were reprocessed after stacking to bring them to the same processing and signal-to-noise ratio standards. The total length of the selected lines is 8000 km. We investigated the character of active faulting in the North Aegean Sea using seismic reflection data. Moreover, the relations of active faults with earthquakes were examined using earthquake fault plane solutions (FPS). We show that the active faults are dominantly normal in character in the NNE Aegean where FPS for earthquakes with M>5 indicate strike-slip movements along these faults. We propose a simple mechanism that potentially explains this inconsistency. Active normal faults are oriented in a NE–SW direction in alignment with the SW escape motion of the Anatolian block in this region and this orientation facilitates instantaneously strike-slip movements along these otherwise normal faults.  相似文献   

Low-magnitude earthquakes in Rome: structural interpretation and implications for the local stress field     

Fabrizio Marra 《Geophysical Journal International》1999,138(1):231-243

  相似文献   

鹿井铀矿田空间定位条件分析   总被引：2，自引：0，他引：2  

张振华  李顺初  翦勋平 《铀矿地质》1999,15(6):338-343

笔者在研究鹿井铀矿田区域地质背景、产铀花岗岩及矿田构造环境的基础上,认为鹿井铀矿田空间定位于特定的区域地质背景及特殊产铀花岗岩体中的独特构造环境中。强调了离散走滑断裂作用（即纵向及横向拉伸作用）控制了鹿井铀矿田的空间分布范围,它是控制鹿井铀矿田的主导因素。  相似文献   

犁式(箕状)断陷盆地的一种模拟方法及其在海拉尔盆地的应用   总被引：1，自引：1，他引：0  

张晓东  李贵顺  李桂荣 《铀矿地质》1999,15(6):361-366

弹性条件下的拉伸速率和由于压实作用而不断变化的沉积物密度满足一定的散度方程。通过有限差分方法解该方程可计算盆地的拉伸量。应用该方法对海拉尔盆地各沉积时期进行了计算,取得了较好的效果,这对盆地的形成和演化以及寻找油气靶区等研究具有一定的指导意义。  相似文献   

���ÿ���-λ��ģ�ͷ��ݻ������������˶��Ͷ��ѻ   总被引：1，自引：0，他引：1  

朱泽  孟国杰  苏小宁  金红林  胡新康  Ge Linlin 《大地测量与地球动力学》2014,34(4):39-42

?????????1999??????GPS?????????д??????????GPS?????????????????????媲λ?????????????????????????????????????????????????????о???????????????壬?о????????????????????С????????????????????????????????????????????????????????????????????????1 mm/a?????κ???α????????????????????????40 km??30 km???????????????????????????????????????1 mm/a??????????????30 km????????????????????????????????1 mm/a?????????????????40 km??  相似文献   

Quaternary normal faulting in southeastern Sicily (Italy):a seismic source for the 1693 large earthquake   总被引：5，自引：0，他引：5  

Marcello Bianca  Carmelo Monaco  Luigi Tortorici  Licio Cernobori 《Geophysical Journal International》1999,139(2):370-394

We present geological and morphological data, combined with an analysis of seismic reflection lines across the Ionian offshore zone and information on historical earthquakes, in order to yield new constraints on active faulting in southeastern Sicily. This region, one of the most seismically active of the Mediterranean, is affected by WNW–ESE regional extension producing normal faulting of the southern edge of the Siculo–Calabrian rift zone. Our data describe two systems of Quaternary normal faults, characterized by different ages and related to distinct tectonic processes. The older NW–SE-trending normal fault segments developed up to ≈400  kyr ago and, striking perpendicular to the main front of the Maghrebian thrust belt, bound the small basins occurring along the eastern coast of the Hyblean Plateau. The younger fault system is represented by prominent NNW–SSE-trending normal fault segments and extends along the Ionian offshore zone following the NE–SW-trending Avola and Rosolini–Ispica normal faults. These faults are characterized by vertical slip rates of 0.7–3.3  mm  yr ⁻¹ and might be associated with the large seismic events of January 1693. We suggest that the main shock of the January 1693 earthquakes ( M ~ 7) could be related to a 45  km long normal fault with a right-lateral component of motion. A long-term net slip rate of about 3.7  mm  yr ⁻¹ is calculated, and a recurrence interval of about 550 ± 50  yr is proposed for large events similar to that of January 1693.  相似文献   

与城市地下生命线工程有关的双层地质结构中的几个问题     

彭一民  孙进忠 《现代地质》1993,7(1):93-101

近代城市地下生命线工程要求对埋藏基岩中的活动断裂作出工程评价,以判断其是否有出现地表破裂的可能。 本文提出了对研究活动断裂的3项内容,即:“活动断裂的活动时间下限、地震复发周期及活动断裂的活动速率;对不同的断裂活动机制,即蠕动和粘滑,从覆盖层厚薄两种情况分析了对地基所产生的影响。 作者通过超声地震模型实验对覆盖层横向非均一性影响地下生命线工程的特点进行了研究,结果表明,横向非均一的覆盖层在地震过程中对地下生命线工程影响显著,不可忽视。  相似文献