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1.
V. A. Saltykov Yu. A. Kugaenko N. M. Kravchenko A. A. Konovalova 《Journal of Volcanology and Seismology》2013,7(1):58-75
This paper presents a set of seismicity parameters that are estimated at the Kamchatka Branch of the Geophysical Service, Russian Academy of Sciences based on the regional catalog data with the purpose of routine monitoring of the current seismic situation in the region. The focus is on the identification of changes in the seismic regime (seismic quiescences and seismicity increases) in earth volumes adjacent to the maturing rupture zone of a large earthquake. The techniques we use include estimation of the seismicity level for the region using the SOUS’09 scale; calculation of the variations in the slope of the recurrence relation, identification of statistically significant anomalies in the slope using the Z test, and calculation of the seismic activity A 10; monitoring the RTL parameter and variations in the area of seismogenic ruptures; using the Z test to detect areas of statistically significant decreases in the rate of seismicity; and identification of earthquake clusters. We furnish examples of such anomalies in these seismicity parameters prior to large earthquakes in Kamchatka. 相似文献
2.
１９９３年第四季度，全球地震活动为中等水平，三个月内共发生三次７．１级浅源地震。新几内亚东部发生６－７级地震多次。美州地震带地震活动表现不强。堪察加以东近海发生７．１级地震。亚欧带于１０月２日发生中国新疆南部（若羌）地震。全球浅源地震相对活跃。 相似文献
3.
N. E. Pribylova 《Journal of Volcanology and Seismology》2012,6(4):254-258
The catalogs of the Kamchatka region contain a damaging earthquake of M = 7.0 that occurred about 100 km east of Petropavlovsk-Kamchatskii City on September 6, 1866. The basis for this location was a single source, namely, the catalog of the French researcher Alexis Perrey. All later investigators of historical seismicity in Kamchatka cite this source. At present, the earthquake referred to is one of the controlling events for the estimation of earthquake hazard for Petropavlovsk-Kamchatskii City and its environs. The goal of the present study is to combine and examine all known and additional sources that contain some information on this event. The materials thus collected provide grounds for considerable revision of this earthquake??s parameters. 相似文献
4.
A comprehensive analysis of Kamchatka seismicity for the period 2005–2007 using the regional catalog
We characterize the Kamchatka seismicity for the period 2005–2007. Regional catalogs of Kamchatka earthquakes were used to
develop 2D distributions of parameters of background seismicity. The characteristics we consider include the activity A
10, the slope of the recurrence curve γ, the parameters involved in the methods RTL, ΔS, and the “Z-function”, as well as the control of earthquake clustering. We have detected the space-time agreement between the anomalies
exhibited by several parameters. 相似文献
5.
—The 1952 Kamchatka earthquake is among the largest earthquakes of this century, with an estimated magnitude of M w = 9.0. We inverted tide gauge records from Japan, North America, the Aleutians, and Hawaii for the asperity distribution. The results show two areas of high slip. The average slip is over 3 m, giving a seismic moment estimate of 155×1020Nm, or M w = 8.8. The 20th century seismicity of the 1952 rupture zone shows a strong correlation to the asperity distribution, which suggests that the large earthquakes (M > 7) are controlled by the locations of the asperities and that future large earthquakes will also recur in the asperity regions. 相似文献
6.
印尼8.7、 8.5级巨震对云南地区地震活动的远震触发分析 总被引：5，自引：0，他引：5
在收集整理印尼8.7、 8.5级巨震活动特点基础上, 分析了这两次巨震对云南地区地震活动的远震触发特征。 依据腾冲、 昆明两个台站的数字波形资料, 对这两次巨震的触发特点进行了分析。 认为云南地区2004年12月26日后地震活动的显著增强, 是由印尼8.7级巨震的长周期面波触发引起的。 8.5级地震后, 云南地区地震活动没有引起触发, 主要原因是8.7级地震已引起相关地震活动, 短期内断层不足以积累使其破裂的能量所致。 远震触发的地区与高热流地区一致。 相似文献
7.
Yu. A. Kugaenko V. M. Pavlov E. I. Ivanova I. R. Abubakirov V. A. Saltykov 《Journal of Volcanology and Seismology》2017,11(6):419-433
This paper reports a study of the Tolud earthquake sequence; the sequence was a burst of shallow seismicity between November 28 and December 7, 2012; it accompanied the initial phase in the Tolbachik Fissure Eruption of 2012?2013. The largest earthquake (the Tolud earthquake of November 30, 2012, to be referred to as the Tolud Earthquake in what follows, with KS = 11.3, ML = 4.9, MC = 5.4, and MW = 4.8) is one of the five larger seismic events that have been recorded at depths shallower than 10 km beneath the entire Klyuchevskoi Volcanic Cluster in 1961?2015. It was found that the Tolud earthquake sequence was the foreshock–aftershock process of the Tolud Earthquake. This is one of the larger seismicity episodes ever to have occurred in the volcanic areas of Kamchatka. Data of the Kamchatka seismic stations were used to compute some parameters for the Tolud Earthquake and its largest (ML = 4.3) aftershock; the parameters include the source parameters and mechanisms, and the moment magnitudes, since no information on these is available at the world seismological data centers. The focal mechanisms for the Tolud Earthquake and for its aftershock are consistent with seismic ruptures at a tension fault in the rift zone. Instrumental data were used to estimate the intensity of shaking due to the Tolud Earthquake. We discuss the sequence of events that was a signature of the time-dependent seismic and volcanic activity that took place in the Tolbachik zone in late November 2012 and terminated in the Tolud burst of seismicity. Based on the current ideas of the tectonics and magma sources for the Tolbachik volcanic zone, we discuss possible causes of these earthquakes. 相似文献
8.
V. I. Levina A. V. Lander S. V. Mityushkina A. Yu. Chebrova 《Journal of Volcanology and Seismology》2013,7(1):37-57
This paper reviews the Kamchatka seismicity for a 50-year period of observation. These data were used to carry out a regionalization of Kamchatka’s seismic volume and adjacent areas. In all, ten zones were identified with differing activities and origins of seismicity. A comparative analysis was carried out for the seismicity in the more active zones. We found significant differences between the structures of the southern and the northern segment in the Kamchatka part of the Kuril-Kamchatka subduction zone. Seismological data corroborated a relationship between the subduction zone and the underthrusting of the Pacific plate under the Eurasian plate. These data from the 50-year period of observation helped identify a new Koryak seismic belt that encompasses the northwestern coast of the Bering Sea. We provide a brief review of macroseismic effects due to the most significant earthquakes for the 1962–2010 period. 相似文献
9.
Machine learning-based automatic construction of earthquake catalog for reservoir areas in multiple river basins of Guizhou province,China 
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下载免费PDF全文 Large reservoirs have the risk of reservoir induced seismicity. Accurately detecting and locating microseismic events are crucial when studying reservoir earthquakes. Automatic earthquake monitoring in reservoir areas is one of the effective measures for earthquake disaster prevention and mitigation. In this study, we first applied the automatic location workflow (named LOC-FLOW) to process 14-day continuous waveform data from several reservoir areas in different river basins of Guizhou province. Compared with the manual seismic catalog, the recall rate of seismic event detection using the workflow was 83.9%. Of the detected earthquakes, 88.9% had an onset time difference below 1 s, 81.8% has a deviation in epicenter location within 5 km, and 77.8% had a focal depth difference of less than 5 km, indicating that the workflow has good generalization capacity in reservoir areas. We further applied the workflow to retrospectively process continuous waveform data recorded from 2020 to the first half of 2021 in reservoir areas in multiple river basins of western Guizhou province and identified five times the number of seismic events obtained through manual processing. Compared with manual processing of seismic catalog, the completeness magnitude had decreased from 1.3 to 0.8, and a b-value of 1.25 was calculated for seismicity in western Guizhou province, consistent with the b-values obtained for the reservoir area in previous studies. Our results show that seismicity levels were relatively low around large reservoirs that were impounded over 15 years ago, and there is no significant correlation between the seismicity in these areas and reservoir impoundment. Seismicity patterns were notably different around two large reservoirs that were only impounded about 12 years ago, which may be explained by differences in reservoir storage capacity, the geologic and tectonic settings, hydrogeological characteristics, and active fault the reservoir areas. Prominent seismicity persisted around two large reservoirs that have been impounded for less than 10 years. These events were clustered and had relatively shallow focal depths. The impoundment of the Jiayan Reservoir had not officially begun during this study period, but earthquake location results suggested a high seismicity level in this reservoir area. Therefore, any seismicity in this reservoir area after the official impoundment deserves special attention. 相似文献
10.
利用地震活动图像演化动态跟踪、地震活动参数时间扫描及震群判定等目前较为成熟的地震预测方法,研究了2001年昆仑山口西8.1级地震前地震活动性异常.结果显示8.1级地震前地震活动性异常有序性明显,地震空区、地震条带、震群活动异常突出,且呈现配套特征.研究认为地震空区图像演化对揭示特大地震的孕育场有所帮助;大范围前兆震群活动是特大地震前多点应力积累、释放的前兆反应;结合地震活动参数扫描异常综合分析,特大地震前可能做出一定的中期-短期预测. 相似文献
11.
丽江7.0级地震前地震分形异常 总被引：2，自引：2，他引：2
本提供了丽江７．０级地震前滇西北地震活动空间容量维、关联维、信息熵十分显的异常图像；这些异常是在大震孕震区形成、应变释放加速阶段之后出现的，恰好揭示了源区、近源区大释放前的非线性变化过程。这与１９６５年以来云南及邻区８组大震前地震分形研究的结论完全一致；进一步说明地震活动分形异常对地震孕育的短临阶段具有重要的指示意义。 相似文献
12.
本文对1988年8月15日澜沧中强震序列,以及1988年11月6日澜沧——耿马强震序列的地震活动性特征和地震波特征进行了探讨。研究表明在某些方面,8月15日中强震序列反映出其前震特征,而11月6日强震序列则明显反映出双震型地震的特征。在余震区的北区和南区,余震活动在地震波初动、震源深度、大小地震比例关系和能量释放等方面均表现出不同的特征。本文同时对强余震前的地震活动性特征作了一些初步的探讨。 相似文献
13.
We investigated the seismicity in the aftershock area of a great earthquake occurring on April 20, 2006 (21:04 LT) in the
area of the Koryak Autonomous Okrug. This analysis of the aftershock process was based on a complete catalog of the earthquakes
that were recorded during April–May 2006 by the regional network of seismic stations operated by the Kamchatka Branch of the
Geophysical Service of the Russian Academy of Sciences. We also made use of a catalog of low magnitude events for May 2–17
as recorded by a mobile seismic network deployed in the rupture zone. We provide a review of seismicity for the Koryak Upland
for the period of instrumental observations in the 20th and early 21st centuries. 相似文献
14.
It is shown that episodes of comparative seismic quiescence that lasted about 20–25 years in the areas of study alternated with intervals of sharply increased seismicity as series of large (M ≥ 6.9) earthquakes occurred during two to three decades. Since no M ≥ 6.6 earthquake has occurred in the area for as long as 21 years after the 1992 Susamyr event, middle-term prediction would require identification of zones of imminent large earthquakes. More reliable identification of such zones rests on data relating to inhomogeneities in the field of S-wave attenuation in the lithosphere, as well as on the characteristics of ring structures of seismicity. Such structures are formed as zones of seismic quiescence that are bounded by M ? Mth earthquake epicenters, where Mth is the threshold magnitude value. Correlative relationships were previously derived, lgL(Mw) and Mth(Mw), for events with different focal mechanisms (L is the length of the longer axis of a seismicity ring and Mw is the magnitude of the associated large earthquake). These relationships were used to estimate the Mw of large events that can occur in these ring structures. The greatest earthquake with Mw ? 7.5 is probably about to occur in southern Tien Shan, east of the 1949 Khait earthquake rupture. A smaller event (Mw ～ 7.0) can occur in the Kyrgyz Range area. Still smaller earthquakes probably have their precursory areas north and east of Lake Issyk-Kul, as well as in Dzungaria. 相似文献
15.
定义了地震活动模糊熵概念，计算了唐山地震前地震活动模糊熵随时间，空间的变化，发现唐山Ｍｓ７．８地震发生前，地震活动模糊熵值下降，唐山Ｍｓ７．８地震发生在地震活动模糊熵值较低的地方，这符合大地震前震源区地震活动从无序趋向有序的规律，地震活动模糊熵反模糊因子与震群活动熵统一起来，比震群活动熵更突出地反映地震活动异常。 相似文献
16.
ＰａｔｅｒｎｓａｎｄｒｅｇｕｌａｒｉｔｙｏｆｒｉｎｇｄｉｓｔｒｉｂｕｔｉｏｎｏｆｓｅｉｓｍｉｃａｃｔｉｖｉｔｙｂｅｆｏｒｅｇｒｅａｔｅａｒｔｈｑｕａｋｅｓｉｎＣｈｉｎａＳＨＩ－ＲＯＮＧＭＥＩ（梅世蓉），ＺＨＩ－ＰＩＮＧＳＯＮＧ（宋治平）ａｎｄＹＡＮ... 相似文献
17.
18.
１９９５年第二季度，全球地震活动恢复到１９９４年的高水平态势：浅源地震频数猛增，并出现两次Ｍｓ７．７以上巨大地震。大洋岛弧带成为本季度地震活动中心。所罗门群岛有两次中强震。菲律宾萨马岛附近发生大震群。千岛群岛大震的余震未息。秘鲁北部和缅印边界各有一次中深源地震。希腊发生中强地震两次。萨哈林岛地震显示全球地震信息。 相似文献
19.
2022年9月5日四川泸定发生M6.8地震,为研究泸定地震孕震区的应力变化,选取b值、小震调制比和丛集率这3个参数,对泸定地震前的区域地震活动状态进行计算研究。结果显示:泸定及周边区域几次强震发生前,区域地震活动均存在持续时间较长的低b值时段,且在低b值状态下震前短期内出现小震高丛集、高调制比的现象;鲜水河断裂带的地震活动状态分析显示,此次泸定地震前该断裂带存在持续时间近10个月的低b值状态,且短期内出现丛集率升高、调制比高值现象。通过对比分析,认为泸定地震是鲜水河断裂带构造运动的结果。综合分析认为,结合应力场背景和构造条件研究地震活动b值、固体潮调制比和丛集率的时空变化有助于理解大地震的孕育演化过程。 相似文献
20.
S. A. Fedotov 《Journal of Volcanology and Seismology》2008,2(2):135-141
Kamchatka and the Kuril Islands (the Kuril-Kamchatka arc) make up the region of highest seismicity in Russia. About 80% of Russian earthquakes occur there, but a mere handful of three seismographic stations had been in operation until the autumn of 1957. On September 2, 1957, the Seismological Team of the Pacific Multidisciplinary Geologic and Geophysical Expedition, Institute of Physics of the Earth, USSR Acad. Sci. set foot on Iturup I, South Kuril Is. to do research for the International Geophysical Year program during 1957–1959, and began detailed seismological investigations in the Kuril-Kamchatka arc. During the subsequent 50 years, six organizations of the USSR/Russian Academy of Sciences conducted and developed this research in the Kuril Is. and Kamchatka. We review previous seismic expeditionary studies, which were carried out in other regions of the USSR from 1949 to 1957. The beginning of the detailed seismological investigations for the Kuril-Kamchatka arc is described, providing brief information on how this research was organized, as well as on the researchers involved, their lines of research, and the development of the extensive and comprehensive studies carried out in 1957–2007, along with some of their leading results. These results include the study of seismicity, its patterns, geodynamics, deep structure, upper mantle properties, the relationships between seismicity and volcanism, and successful long-term earthquake forecasts, among other subjects. 相似文献