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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. [ABSTRACT FROM AUTHOR]

This paper presents the main results from the development of the detailed seismological observation system in Kamchatka and the information on the system as of 2011. We describe the networks of seismological stations, the systems for the acquisition, storage, and processing of seismological observations and their technical, methodological, and software support. We discuss the basic characteristics of the recording channels and the system as a whole. We present the information resources of the Kamchatka seismological data bank that provide for basic research in earth sciences. In 2011, the system of seismological observation in Kamchatka was a specialized network for acquisition (recording), storage, transmission, and processing of seismic and geophysical data that provides support for the effective monitoring of seismic and volcanic activities, as well as tsunami warning. [ABSTRACT FROM AUTHOR]

Seismological Observations in Kamchatka were significantly improved due to the installation of new telemetered seismic stations near active volcanoes and the implementation of modern digital technologies for data transmission, acquisition, and processing in 1996-1998. This qualitative leap forward made it possible, not only to create an effective system for monitoring Kamchatka volcanoes and for timely and reliable assessment of the state of these volcanoes, but also to draw conclusions about volcanic hazard. The experience that was gained allowed us to make successful short-term forecasts for eight moderate explosive eruptions on Bezymyannyi Volcano of the ten that have occurred in 2004-2010, successful intermediate-term forecasts of evolving activity on Klyuchevskoi Volcano in three cases, as well as providing a successful forecast of an explosive eruption on Kizimen Volcano. [ABSTRACT FROM AUTHOR]

Three strong earthquakes that occurred since the end of 8th century have been identified by archeoseismic data in the southwestern part of the Tere Khol' Depression. The dates for these events are the 9th, 12th, and first two-thirds of 19th century, and the average recurrence interval is 500 years. The relative seismic passivity of the Tere Khol' Depression at present may be related to the relatively recent discharge of stress in seismogenerating sources. [ABSTRACT FROM AUTHOR]

Abstract: Combined reflection (CDP) and refraction/wide-angle reflection (DSS) studies were carried out along the 2-AR profile from the center of the Barents Sea across the Novaya Zemlya Island and the Kara Sea. A dense system of observations with intervals between the bottom stations of 10 km enables to determine detailed velocity models of the crust and uppermost mantle and to value of roles of CDP and DSS surveys in the studies. They are used also for a comparison between possibilities and limitations of different methods of the DSS data interpretation (1D solution, tomographic modeling, the Moho imaging and ray-tracing). The studies show the continental crust with average thickness of 35–37 km in the sea areas and of 40–45 km beneath the Novaya Zemlya. In the deep basins filled with 7–14 km thick sediments, the crystalline crust is reduced with the Moho rising. The crustal structure is complicated by fault zones which divide the crust in blocks with different tectonic regimes. The largest fault of listric form crosses the whole crust between the Novaya Zemlya and the South-Kara basin. Several rift grabens and faults are revealed in the basin basement. This confirms the idea that the basin formation started from narrow rift grabens. Beneath the Moho several inclined boundaries are traced down a depth of 60 km. [Copyright &y& Elsevier]