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1.
Sediment yield of Kamchatka Krai rivers into the Pacific Ocean and the seas of Bering and Okhotsk, is evaluated, including that from the drainage basins that are not covered by regular observations. Regression dependences of specific suspended sediment yield (SSSY) on factors determining it were constructed for erosion regions identified in Kamchatka Krai. The total average many-year yield of suspended sediments of Kamchatka Krai rivers into the Pacific is 11.4 × 106 t/year, 73.9% of which is transported by rivers of the eastern coast and 26.1%, by those of the western coast. Among other factors, such distribution is attributed to the location of the majority of volcanoes on Kamchatka eastern coast. About one third of all sediments transported from Kamchatka Krai territory is discharged by the two largest rivers in the region, i.e., the Penzhina and Kamchatka.  相似文献   

2.
We consider the key features in the responses of magnetic tippers and MTS curves to the sharp contrast in electric conductivity at the interface between the land and the sea waters of the Sea of Okhotsk and the Pacific bounding Kamchatka. The zones with different intensity of the coast effect are revealed. Stronger manifestations of the effect are found to occur in the East Kamchatka, which is related to the induction effects of the electric currents concentrated in the Kuril-Kamchatka trench. Indentation of the coastline resulted in the appearance of three-dimensional (3D) effects in the magnetotelluric field of the eastern Kamchatka. These effects in the variations of the geomagnetic field are vanishing with an increasing period, giving room to low-frequency effects in the MT field, which are associated with the flow of electric currents around Kamchatka (the around-flow effect). It is shown that the transverse MTS curves over the entire region of Kamchatka suffer from the S effect at low frequencies and do not characterize the deep geoelectric structure. Only in the middle segments of the West and Central Kamchatka, the longitudinal MTS curves are weakly subjected to the induction effects and thus reflect the distribution of the deep electric conductivity. On the eastern coast of Kamchatka both the longitudinal and transverse MTS curves are strongly distorted by the 3D effects caused by the abundant capes and bays. The interpretation of MTS data in this region should necessarily invoke the 3D modeling of an MT field.  相似文献   

3.
Ocean Dynamics - We used historical CTD observations and Argo data to obtain the characteristics of the Kamchatka Current halocline and its eddies. Kamchatka Current eddies have a cold low salinity...  相似文献   

4.
This is a review of the geodetic monitoring of the horizontal component of recent crustal movements (RCMs) in Kamchatka and the Commander Islands for the period 1979–2007. Examples are provided of the RCMs recorded in Kamchatka and the Commander Islands for the period 1997–2007 by the Kamchatka regional GPS network (KAMNET) set up by workers at the Kamchatka Branch of the RAS Geophysical Service (KB GS RAS) in collaboration with the Institute of Volcanology and Seismology of the Far East Division of the Russian Academy of Sciences to study the geodynamic processes that are occurring in the Kamchatka subduction zone. An interpretation of examples of recorded RCMs is given.  相似文献   

5.
Kamchatka and the Kuril Islands are home to 36 active volcanoes with yearly explosive eruptions that eject ash to heights of 8 to 15 km above sea level, posing hazards to jet planes. In order to reduce the risk of planes colliding with ash clouds in the north Pacific, the KVERT team affiliated with the Institute of Volcanology and Seismology of the Far East Branch of the Russian Academy of Sciences (IV&S FEB RAS) has conducted daily satellite-based monitoring of Kamchatka volcanoes since 2002. Specialists at the IV&S FEB RAS, Space Research Institute of the Russian Academy of Sciences (SRI RAS), the Computing Center of the Far East Branch of the Russian Academy of Sciences (CC FEB RAS), and the Far East Planeta Center of Space Hydrometeorology Research (FEPC SHR) have developed, introduced into practice, and were continuing to refine the VolSatView information system for Monitoring of Volcanic Activity in Kamchatka and on the Kuril Islands during the 2011–2015 period. This system enables integrated processing of various satellite data, as well as of weather and land-based information for continuous monitoring and investigation of volcanic activity in the Kuril–Kamchatka region. No other information system worldwide offers the abilities that the Vol-SatView has for studies of volcanoes. This paper shows the main abilities of the application of VolSatView for routine monitoring and retrospective analysis of volcanic activity in Kamchatka and on the Kuril Islands.  相似文献   

6.
This study is concerned with seismicity variations in Kamchatka and the Kuril Islands for the period 1962–2009; the effects of large earthquakes on the seismicity of adjacent areas are taken into account. The 1997 Kronotskii earthquake was followed by seismicity decreases in most areas over Kamchatka, which is presumably related to decreased tectonic stresses. After the 2007 Simushir earthquake synchronization and periodicities in seismicity were identified, indicating increased instabilities and the likelihood of a large event in Kamchatka in the near future. The instability of seismic regions is discussed within the framework of the theory of nonequilibrium dynamical systems. We suggest successive phases in the occurrence of seismological precursors.  相似文献   

7.
Early warning systems are becoming increasingly important in the modern world. These systems combine several components: predictive systems (For example, tsunami warning systems), earthquake early warning systems, emergency message services, and systems of seismic damage monitoring. Information about shaking intensity becomes especially important in the case of a strong earthquake occurrence. These data are necessary for planning emergency rescue operations, but they are difficult to collect in a natural disasters situation because of possible communication problems. Application of data on instrumental seismic intensity may make it possible to solve this problem. Early warning systems predicting seismic intensity distributions just after the occurrence of an earthquake have already been developed in many seismically active regions of the world. Such a system also needs to be implemented in Kamchatka, where the strongest earthquakes can produce extremely high values of strong motion acceleration. As a result of the development of a system for seismological observation in Kamchatka, a unified specialized system for collection, transmission, archiving, and processing of seismic information was created. Seismological observations in Kamchatka were significantly improved with the update of the tsunami warning service in 2006–2011. As a result, a network of strong motion stations is currently operating in Kamchatka and can serve as a basis for creating a quasi-real-time seismic early warning system under the auspices the Kamchatka Branch of the Geophysical Survey, Russian Academy of Sciences (KB GS RAS). It uses data from strong motion stations to estimate the instrumental seismic intensity in quasi-real-time mode and visualizes the results. During the operational period while the service is being intensively used in the framework of the Seismic Early Warning Reports Tsunami Warning Service in the Kamchatka and Sakhalin branches of the GS RAS for real-time warning of interested parties about the shaking intensities at observation points, the technology implemented in this service has proved highly informative. In total, 75 messages on instrumental intensity in various places of Kamchatka krai and the northern Kuril Islands (Paramushir Islands) have been sent since the service was commissioned at the end of 2014. The currently operating version of the service has proved its informativeness and applicability for special departments of the Emergency Situations Ministry. In addition, real-time warning has improved coordination between the departments of KB GS RAS, and the results of this system are being used in a number of basic research projects. Further development of the service is related to the creation of denser instrumental networks to record strong ground motions and the transition to automatic decision-making and message sending.  相似文献   

8.
The KamIn information system (IS) created at the Kamchatka Branch of GS RAS to collect, store, and preprocess data on the wave perturbations in the atmosphere is described. The KamIn IS observation system and infrastructure are described in detail; they make it possible to select infrasonic signals that occur during volcanic eruptions on Kamchatka and in the northern Kurile Islands both in the operational and regular mode. The results of the IS performance in 2010–2016 are summarized.  相似文献   

9.
In this paper compressional and shear wave velocities at quasihydrostatic pressures up to 20–30 kb are reported for rocks of the Kamchatka peninsula. Discussions of the results are made in terms of possible interpretation of the seismic wave velocity distribution in the upper mantle under Kamchatka, which was established by seismological methods. A number of assumptions are made about the composition and the physical conditions of the upper mantle under Kamchatka.  相似文献   

10.
This paper presents new data on the upper mantle characteristics, and on seismicity and volcanism in Kamchatka. It is shown that the seismic activity in the Pacific focal layer decreases sharply below that narrow line on which the foci of the active volcanoes are situated. A map of longitudinal wave velocitiesV p in the mantle upper layers under Kamchatka is given. The lowest values ofV p (7.3–7.6 km/sec) are found near the volcanic belt. The graphs Θ=lg (Es/Ep) (h) for the Kamchatka earthquakes indicate that Θmin at the depths of 120–250 km may be caused by a concentration of magmatic melts. A map of bodies (magma chambers?) screening S- and P-waves at the depths of 30–100 km under Kamchatka has been compiled. These bodies are mainly located under the belt of active volcanoes.  相似文献   

11.
The experimental MT data and theoretical data calculated by the thin sheet technique for a low-frequency telluric field are analysed and compared for the Kamchatka Peninsula. The comparison shows a good agreement between the experimental and theoretical data and results in a conclusion that the DC-type distortions of the telluric field play the most important role in the structure of the MT field. The component of the telluric field which is parallel to the general direction of the Kamchatka Peninsula is less distorted and should be used for the estimation of deep geoelectric structures.  相似文献   

12.
The MTS data acquired in Kamchatka during the last 30 years have been analyzed and summarized. Our interpretation is based on curves oriented along and across Kamchatka. Longitudinal and transverse curves can be affected by local geoelectric inhomogeneities. These were suppressed by conformal averaging. A bimodal interpretation of average longitudinal and transverse curves yielded a deep geoelectric model, which can be adopted as a starting point to be subsequently refined by 3D numerical modeling. The model involves a crustal conductive layer extending along central Kamchatka. In the east of the peninsula this layer is connected with crustal transverse conductive zones as wide as 50 km. Those zones have extensions toward the Pacific Ocean. Major centers of present-day volcanism occur in the transverse zones. The upper mantle contains an asthenospheric conductive layer forming an uplift beneath the present-day volcanic belt of Kamchatka.  相似文献   

13.
Using Lagrangian methods, we analyze a 20-year-long estimate of water flux through the Kamchatka Strait in the northern North Pacific based on AVISO velocity field. It sheds new light on the flux pattern and its variability on annual and monthly time scales. Strong seasonality in surface outflow through the strait could be explained by temporal changes in the wind stress over the northern and western Bering Sea slopes. Interannual changes in a surface outflow through the Kamchatka Strait correlate significantly with the Near Strait inflow and Bering Strait outflow. Enhanced westward surface flow of the Alaskan Stream across the 174°E section in the northern North Pacific is accompanied by an increased inflow into the Bering Sea through the Near Strait. In summer, the surface flow pattern in the Kamchatka Strait is determined by the passage of anticyclonic and cyclonic mesoscale eddies. The wind stress over the Bering basin in winter–spring is responsible for eddy generation in the region.  相似文献   

14.
堪察加地区现今地壳运动与变形特征研究   总被引：2，自引：1，他引：1       下载免费PDF全文
利用俄罗斯堪察加地区1995～2005年的GPS观测数据,研究了该区现今地壳水平运动速度场特征.在球坐标系中解算了各应变率分量,分析了应变率场的空间分布特征,并与地震学和地质学研究结果进行了综合对比分析.结果表明,堪察加半岛北部的微板块边界并不明显,堪察加南部测站运动速度大于中部和北部地区,愈靠近东部板块汇聚区,测站速度越大.从东海岸到西海岸,测站水平速度存在明显的梯度衰减特征,水平运动方向与太平洋板块向西北的俯冲方向基本一致.各应变率分量具有东部海岸大于中部和西海岸、从东至西呈梯度衰减的特点.堪察加大部分地区处于EW和NS向压缩状态,局部存在拉张.面应变率结果显示绝大部分为压缩区;刚性转动结果表明大部分地区表现为顺时针转动,北部地区和南端顺时针旋转性明显.东部有效应变率明显大于西部地区,东西向梯度衰减关系明显.主压应变率明显大于主张应变率,特别是在东海岸地区.主压应变率方向与中等以上地震的主压应力轴在水平方向的投影方向基本一致.地壳变形场在空间分布上的不一致性主要与太平洋板块在堪察加半岛东南侧的俯冲深度、俯冲方位角、俯冲倾角和俯冲带的耦合强度有关.  相似文献   

15.
The Kuril-Kamchatka subduction zone is the most mobile and seismically active region in Northeast Eurasia. The Kuril island arc is one of the few tectonically active regions, where until recently there had been no space geodetic network. The first GPS stations were installed on the Kamchatka Peninsula in 1997, and on the islands of the Kuril arc from Kamchatka to Hokkaido, in 2006. The collected geodetic data allowed us to reveal the geometry of the interplate coupling along the whole Kuril-Kamchatka arc, and also to estimate the source parameters and their features for a number of major earthquakes in this area.  相似文献   

16.
In 2005, six major eruptions of four Kamchatka volcanoes (Bezymyannyi, Klyuchevskoy, Shiveluch, and Karymskii) occurred and the Avachinskii, Mutnovskii, and Gorelyi Kamchatka volcanoes and the Ebeko and Chikurachki volcanoes in northern Kurils were in a state of increased activity. Owing to a close collaboration between the KVERT project, Elizovo airport meteorological center, and volcanic ash advisory centers in Tokyo, Anchorage, and Washington (Tokyo, Anchorage, and Washington VAACs), all necessary measures for safe airplane flights near Kamchatka were taken and fatal accidents related to volcanic activity did not occur.  相似文献   

17.
Eight strong eruptions of four Kamchatka volcanoes (Bezymyannyi, Klyuchevskoi, Shiveluch, and Karymskii) and Chikurachki Volcano on Paramushir Island, North Kurils took place in 2007. In addition, an explosive event occurred on Mutnovskii Volcano and increased fumarole activity was recorded on Avacha and Gorelyi volcanoes in Kamchatka and Ebeko Volcano on Paramushir Island, North Kurils. Thanks to close cooperation with colleagues involved in the Kamchatkan Volcanic Eruption Response Team (KVERT) project from the Elizovo Airport Meteorological Center and volcanic ash advisory centers in Tokyo, Anchorage, and Washington (Tokyo VAAC, Anchorage VAAC, and Washington VAAC), all necessary precautions were taken for flight safety near Kamchatka.  相似文献   

18.
Three complete data sets of strong earthquakes (M5.5), which occurred in the seismic regions of Chile, Mexico and Kamchatka during the time period 1899–1985, have been used to test the existence of a time-lag in the seismic energy release between these regions. These data sets were cross-correlated in order to determine whether any pair of the sets are correlated. For this purpose statistical tests, such as theT-test, the Fisher's transformation and probability distribution have been applied to determine the significance of the obtained correlation coefficients. The results show that the time-lag between Chile and Kamchatka is –2, which means that Kamchatka precedes Chile by 2 years, with a correlation coefficient significant at 99.80% level, a weak correlation between Kamchatka-Mexico and noncorrelation for Mexico-Chile.  相似文献   

19.
A seismological study of the upper mantle under the Kamchatka volcanoes using body waves from nearby earthquakes has shown local heterogencities consisting of materials with reduced elastic properties at depths from 30 to 90 km. The estimated value of the upper limit of viscosity,η, is about 6 × 1020 pois for the material of the mantle aseismic zone under the Kamchatka volcanoes at depths of ～ 70–150 km. It is suggested that the magmatic chambers are rooted in the mantle heterogeneities filled with substance of reduced elasticity and viscosity.  相似文献   

20.
The dynamics of climate and runoff characteristics are studied in the territories of Kamchatka Peninsula and Taiwan Island, which are situated in the influence zone of monsoon circulation. Long-term variations in the temperature, precipitation, and runoff are examined in Kamchatka and Taiwan for the weather and gauging stations with the longest observation series to analyze new climate conditions of water resources generation.  相似文献   

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