Abstract Aftershock sequences have been identified for 60 earthquakes (K ≥ 11) from the catalog of the Institute of Seismology, National Academy of Sciences, Kyrgyz Republic (to be referred to as KIS in what follows). The catalog includes 56 259 events that have occurred in Tien Shan and North Pamir during the period from 1980 to 2001. We have obtained some statistical characteristics of the catalog

Abstract Rapid and reliable tsunami forecasting for regions close to the epicenter of an undersea earthquake remains an unsolved problem. The only method of rapid tsunami hazard estimation used in Russia is the magnitude criterion. It leads to an unacceptably high percentage of false alarms. One promising new method is the modeling of the earthquake source based on the coseismic displacements recorded

Abstract Alaid Volcano on Atlasov Island is the northernmost and highest volcano of the Kuril island arc. The first time lavas were discharged by the terminal eruption of 2015–2016 was in October 2018. The samples were studied by petromagnetic, petrogeochemical, and microprobe techniques. The chemical composition of the 2015–2016 ejecta is very similar to that of the 1933–1934, 1972, and 1981 eruptions

Abstract This paper presents the results of analysis of the spatial distribution of repeated shocks. Data from the world earthquake catalog of USGS/NEIC from 1973 to 2014 were used. Short time intervals, no more than 10 hours after the main shock, and distances from the epicenter of the main shock, no more than 5°, were considered. The dependence of the number of repeated shocks on the distance from

Abstract For the first time, the thermal behavior of a new mineral belomarinaite KNaSO4 from volcanic exhalations (trigonal crystal system, Sp. gr. P3m1, a = 5.6072(3), c = 7.1781(4) Å, V = 195.45(2) Å3) was studied on a natural sublimate sample from the 2012–2013 Tolbachik Fissure Eruption and its synthetic analogue, a low temperature (LT) polymorph of (Sp. gr. P3m1) in the range 30–800°C (high-temperature

Abstract Multidisciplinary geophysical surveys have been carried out in the Pauzhetka hydrothermal system area and around in order to identify 10–15-km deep geological structures that exercise thermal control of the system. The results of vertical electrical and electromagnetic sounding, magnetometric and gravity surveys have been integrated, and geological–geophysical data have been generalized, to

Abstract This paper is a review of a long-continued research by many Russian and foreign scientists in the theory of self-organized criticality (SOC) in application to seismological data. We mean the Unified Scaling Law for Earthquakes (USLE). This law uses the spatial similarity of earthquake epicenters to derive a generalization of the classical Gutenberg–Richter relation. We discuss why this generalization

Abstract The method for constructing the generalized vicinity of a large earthquake as put forward and implemented in (Rodkin, 2008, 2012, 2020; Rodkin and Tikhonov, 2016) was previously used for analysis of world earthquake catalogs only. The use of this method for the analysis of regional catalogs presupposes a lower magnitude threshold for classification of large events and incorporation of regional

Abstract One of the main natural disasters is explosive volcanic eruptions, often lasting 2–4 months. It is obvious that such eruptions of volcanoes cause simultaneous mass release of gas bubbles from the melts of their shallow peripheral chambers, which must lead to a sharp increase in the volume of material contained in them, i.e., to explosions. It is shown that the main prerequisite for an explosive

Abstract Bezymianny Volcano is one of the most active volcanoes in Kamchatka and in the world. This paper describes the preparation, behavior, products, dynamics, and the geological effect of the March 15, 2019 explosive eruption of the volcano, which was predicted 6.5 h before it began. The sequence of eruptive events was analyzed using data provided by video and satellite-based monitoring of the

Abstract This paper is a review of current concepts concerning the seismotectonics and seismicity in the Laptev Sea region. The chief feature of the region is a rift system extending in the shelf from the continental slope with the adjacent Gakkel Ridge to the mainland coast. There are several models to describe the present-day evolution of the region, but no one of these is preferable because of the

Abstract This paper provides information on the structural setting and ore composition of the Nevenrekan deposit. We provide an account of the regional and local factors of mineralization control. The ore bodies are confined to the junction between regional faults and annular ruptures of a circular subsidence. The geochemical zoning of the ore field is disturbed. We show how geochemical associations

Abstract The study of the evolution of large igneous provinces showed that the Archean and Early Paleoproterozoic mantle plumes were formed by high-Mg ultramafic rocks and looked like thermal plumes. However, this situation experienced a cardinal change in the mid-Paleoproterozoic ~2.3 Ga, when an irreversible change occurred in the composition of these plumes, providing evidence of an essentially

Abstract The article is devoted to the results of mineralogical and geochemical studies of argillizites at Compleksnoe Au–Ag ore occurrence, localized on the southern flank of the Kajenmyvaam volcanic uplift in the inner zone of the Late Cretaceous marginal–continental Okhotsk-Chukchi volcanic belt (OChVB). At the ore occurrence, a series of isometric (oval) in plan view argillizite “hats” with diameters

Abstract In recent years three new problems emerged in aftershock physics. We shall refer to these problems in a preliminary way as the dynamic, the inverse, and the morphological problem. They have been distinctly stated, partially solved, and have a fundamental character. The dynamic problem consists in searching for the effect of a circumnavigating seismic echo that occurs after the main shock of

Abstract All known mantle plumes are characterized by a divergence between the location of the extreme heat flow and the recent volcanism center. To explain this phenomenon, it is proposed to consider the Coriolis effect influence, which deflects the magma flow within a mantle plume from the trajectory that is orthogonal to the planet surface. A formula was used that relates the deviation, the latitude

Abstract Seismicity began to be recorded in October 2017 around the dormant Bolshaya Udina Volcano (B. Udina in what follows) situated 10 km southeast of Plosky Tolbachik Volcano. Seismic tomography showed the existence of a long-lived magma chamber south of B. Udina in the area of the Tolud River. The chamber has its top at a depth of about 15 km, and may probably be connected to the Plosky Tolbachik

AbstractMultidisciplinary petrologic, mineralogical, and geochemical studies have been carried out for the first time concerning near-crater tephra from the world-largest intraplate stratovolcano (Erebus). The volcano is characterized by a unique basanite–phonolite effusive lineage. We studied the grain-size and chemical compositions of the tephra and the concentration of trace elements in it, the

AbstractA swarm of volcanic earthquakes that occurred during an eruption of Kizimen Volcano provided an opportunity to study the attenuation of seismic wave energy in volcanogenic rocks at short hypocentral distances from the volcano. The study is based on P and S waves, as well as coda waves, using frequency dependent and frequency independent methods: pulse broadening, code normalization, and the

AbstractWe estimated the level of seismic noise for stations of the KyrgyzNetwork (KNET) for 19 years of its operation (1999–2017) in real time. For each channel of a seismic station (east–west, north–south, vertical) we selected fifteen-minute segments of 100-Hz seismic noise distributed over all seasons of the year (March, June, September, and December) and several times of the day (0, 6, 12, and

AbstractWe have conducted paleo- and archaeoseismological surveys in the Durankulak Eneolithic archaeological settlement in northeastern Bulgaria, identifying many earthquake-related deformations of different ages. The ubiquitous presence of counterfort walls added to damaged original (nearly north–south) walls on the eastern side provides evidence of the first significant earthquake in Durankulak

AbstractThis article considers the conditions for the Au–Ag epithermal mineralization of the Arykevaam volcanic field (AVF) located in the middle of the Chukotka segment of the inner zone of the Okhotsk–Chukotka volcanic belt (OChVB). The results of thermo- and cryometric studies of fluid inclusions in quartz showed that epithermal mineralization was deposited by homogeneous hydrothermal fluids with

AbstractSatellite imagery was used to identify active neotectonic faults. The areas of greater fault density coincide with concentration zones of earthquake epicenters, including the largest of them (K ≥ 10). The earthquakes are confined to intersections of deep NE and NW striking faults. The Kulu–Tenka region can be considered as the area of interaction between the zones of dynamic influence of faults

AbstractRecords of an IRIS broadband seismic station (AAK) deployed in the Tien Shan area were studied. An STS-1 seismometer made it possible to investigate ground motion velocity in the range of a few minutes. The result was to identify asymmetric anomalies in seismic noise that differ from Earth tidal variations. These indicate the effects of local tectonic processes during some time intervals. Several

AbstractThis new seismic tomography study for the crust of southern Crimea and the northeastern Black Sea based on low-magnitude (M ≤ 3) earthquakes indicates significant heterogeneity of the crust at depths of 15–35 km. In the present paper we discuss the velocity distribution for P- and S-waves and give geological and tectonic interpretations in the context of collisional interaction between the

AbstractThis study is concerned with the mineralogical composition of volcanic ejecta in the Central Kamchatka Depression: the plateau basalts of the Ozernaya Kamchatka, Kunch, and Nikolka Stratovolcano. These data were compared with rock compositions for some volcanoes in the Klyuchevskoi Group, the plateau basalts of Bakening Volcano, and data on xenoliths of two types, viz., the “island-arc” type

AbstractThis paper presents the results of areal seismic studies in the deep structure of the Dzhau Tepe mud volcano, which is the largest of its kind on the Kerch Peninsula. It is the first time that data has been obtained concerning nearly vertical fluid-conducting structures beneath the volcano that supply material onto the ground during more active periods. A new approach is proposed for interpretation

AbstractThis paper presents the results of mineralogical and crystallographic studies in the first Russian finding of a mineral belonging to the fluoride class, viz., knasibfite, which was found in fumarolic deposits discharged during the Great Tolbachik Fissure Eruption. We investigated its crystal structure to corroborate the fact that knasibfite is orthorhombic, sp. gr. Imm2; a = 17.181 (2), b =

AbstractThis paper is devoted to the age, stratigraphic position, and structure of the ignimbrite that occurs in NW Armenia, which is locally named “Leninakan tuff.” The massive structure of the tuff with no internal discontinuities, similar chemical composition and K–Ar ages of all the samples let the authors to deduce that the ignimbrite was formed due to a huge single explosive eruption of the Aragats

AbstractThe main subject of this article is research on the genetic relationships in the K–Na subalkaline series that occurs in the Belogolovsky volcanic center located in the back part of Sredinny Range. The differentiated rock series includes trachybasalts, trachyandesites, trachytes, comendite, trachytes, and comendites. Mass balance calculation and trace element modeling show that crystal fractionation

AbstractThe Klyuchevskoi stratovolcano is one of the largest and most active volcanoes in the world; changes of varying sizes have affected the morphology of its surface during historical time. These rock failures mostly occur in long-lived geologic features, namely, volcano-tectonic chutes. Several researchers have made forecasts of failures based on the relief and morphology of the volcano, the system

AbstractThis paper describes a method for calculating the earthquake energy class for the Kamchatka region from coda records in the 0.8–1.8 Hz frequency band. The method is based on an empirical correlative relationship between the coda level and the Fedotov earthquake class. The coda level is found as the mean power of the ground velocity in an interval of 30 s. Five seismic dipping zones have been

AbstractThe geysers and paleo-geysers that exist in Kamchatka are situated in volcanogenic artesian basins composed of products of recent acid volcanism. This is in accord with the worldwide patterns for the occurrence of geyser fields. The results of a TOUGHREACT simulation of flow-through ascending circulation of thermal waters, which have chemical compositions in agreement with that of the water

AbstractAn M 7.4 earthquake occurred near the town of Izmit on August 17, 1999 causing enormous casualties and economic losses: over 15 000 victims and several thousand irreparably damaged buildings and structures. The earthquake produced a set of fractures and fissures in the ground extending for more than 70 km from the Gulf of Izmit, with a new tectonic fault being formed that is more than 150-km

AbstractWe show that volcanic activity was occurring in the NW Pacific seafloor areas adjacent to Japan, the Kuril Islands, Kamchatka, and the Commander Islands during Pliocene to Pleistocene time. The activity was highest in two areas. At least three major volcanoes originated and were active in the southern area behind the Japan trench off Honshu and Hokkaido. Lava-dominated Pleistocene stratovolcanoes

AbstractThe early 21st century saw increased eruption activity of major volcanoes in the Northern Group of Kamchatka, namely, Sheveluch, Klyuchevskoy, Bezymianny, and the Tolbachik Fissure Zone. The growth of an extrusive dome on Sheveluch andesitic volcano has occurred, with the dome reaching a height of 600 m after 38 years of nearly uninterrupted eruption activity. An 8-year period of relative quiet

AbstractPrevious publications by this author (Rodkin, 2008a, 2008b, 2012; Rodkin and Tikhonov, 2016; Rodkin and Rundkvist, 2017) proposed and actually used a method for constructing and analyzing the generalized vicinity of large earthquakes (GVLE). The GVLE method provides an enormous increase in the amount of data that is used and, hence, a much more detailed description of the typical features in

AbstractAn extended and improved model of the origin and evolution of marginal seas in the strike-slip megazone due to the lateral interaction of the Eurasian and Pacific lithospheric plates is proposed. In the megazone, fragmentation of continental and oceanic plates, mantle upwelling, and ascending and descending lithospheric seismic vortexes occur. As a proof of the validity of the proposed model

AbstractThe paper assessed the predictability of the seismic energy rate and large earthquakes in southern Europe and the Mediterranean according to the data from the United States Geological Survey catalog for 1900–2016. A nonlinear second-order differential equation is used as a mathematical model, and optimization and predictability estimation algorithms are this author’s. The estimates show a high

AbstractThe Omori law for repeated underground shocks after a large earthquake is written here in the form of a nonlinear differential equation. We define a coefficient of deactivation for the rupture zone after the main shock. Two advantages of the new formulation are pointed out. First, there is now an interesting possibility for a natural incorporation of exogenous and endogenous factors that affect

AbstractThe probable geothermal reserves of Kamchatka are sufficient to produce 3900 MW of electrical energy. Analogous reserves for heat production are estimated as 1350 MWT (thermal units). The TOUGH2 thermohydrodynamic simulation of extraction for the identified productive geothermal reservoirs with established permeability–capacity and energy properties allows us to predict the following: (1) a

AbstractThe explosive atmospheric electrogenic paragenesis we studied was found to contain over 100 mineral species, varieties, and non-crystalline phases (carbonaceous minerals, phases and compounds, native metals and alloys, carbides, silicides, nitrides, halides, chalcogenides, oxides, silicates and alumosilicates, and oxysalts. The paragenesis is characterized by an abnormally low level of mineralogical

AbstractThis paper discusses currently interesting aspects of metallogeny at the Pacific volcanic belts (PVBs); these consist of complex volcanogenic–plutonic features related to the evolution of the marginal-sea lithosphere, which exhibits a remarkable mineralization peculiarity. We show that as time has passed, the ideas of a metallogenetic homogeneity of the PVBs received a new substantiation from

AbstractThis paper is concerned with results from ongoing work using the method of long-term earthquake prediction (LTEP) for the Kuril–Kamchatka island arc based on the seismic gap and seismic cycle patterns. We highlight the most important lines of research in the LTEP method during the preceding decade. A long-term forecast is provided using the basic method for the next 5 years, June 2019 through

AbstractAn analysis of deep structure for the East Greenland margin (Blosseville Kyst – Liverpool Land) and the Jan Mayen microcontinent yielded a common crustal model for the time before their dispersal. The joint model presents a visual picture of the net result from the Paleozoic, Mesozoic, and Cenozoic rifting phases. Beginning from the Devonian, a graben-like depression approximately 180 km wide

AbstractThis paper discusses the conditions of generation for the Au–Ag epithermal mineralization in the Amguema–Kanchalan Volcanic Field (AKVF), which is situated at the western termination of the East Chukchi flank zone of the Okhotsk–Chukchi Volcanogenic Belt (OChVB). The AKVF contains the potentially large Valunistoe Au‒Ag deposit and several promising deposits and ore occurrences (Zhilnoe, Shakh

AbstractThis paper gives measured quantities, inclined distances, and elevations between geodetic monuments on the northeastern slope of Klyuchevskoi Volcano for the period from 1978 through 2014. Parasitic and summit eruptions were generally preceded by uplifts of the slope, while the termination of an eruption was accompanied by subsidence. The data from the longest series of observations of vertical

AbstractThis paper is concerned with spatial relationships between seismic zones in the eastern Priamurye region (М ≥ 5) on the one hand and, on the other, regional faults and zones of hidden faults as indicated by axes of gravity and magnetic anomalies. The seismoactive zones where М ≥ 5 earthquakes occurred are mostly confined to regional faults, while there are two cases where no such relationship

AbstractEjecta of recent volcanic eruptions were found to contain a carbonaceous mineral phase paragenesis of explosive atmospheric electrogenic origin. The paragenesis involves diamonds of octahedral habitus with non-aggregated nitrogen defects (without signs of mantle burning), disordered graphite, shungite-like bitumen (kerite–anthraxolite), carbonaceous globules (clustered allotropes of dicarbon

AbstractWe have studied paleoseismicity along the adyr (piedmont) Kokonadyr–Tegerek fault zone in the SW Issyk-Kul region. We have shown that although earthquake slip continues in the tectonic contact zone between the Paleozoic rocks of the Kokonadyr–Tegerek uplift and the Quaternary deposits of the Alabash–Konuroleng trough, still most earthquake-generating ruptures visible at the surface are moving

AbstractThe relationship between the chemical composition of plants and the active volcanism of Kamchatka is determined by the fact that the dominant chemical elements for the plants, volcanic ashes, and soils are invariably Ca, Mg, Mn, P, Cu, Zn, and Sr. We have found an increased geochemical background for Kamchatka plants relative to the bulk chemical composition of the soils in the peninsula. The

AbstractThis paper reports numerical modeling work for the polycondensation of orthosilicic acid (OSA) and the growth of the number of silica particles (SiO2) in hydrothermal solutions under a variety of physical and chemical conditions: temperature, pH, ionic strength, etc. We have derived relationships to calculate the concentration of orthosilicic acid and the mean radii of silica particles in relation

AbstractTo highlight the importance of small earthquakes in seismic hazard, we present a study of the 11 May 2016, Mw 4.9, Tesistan earthquake. According to historical data from instrumental seismicity, this earthquake represents the largest event recorded near Guadalajara. Due to the close proximity of the event to the city, accelerations were considerable higher than those caused by historical severe

AbstractThe edifices of many active volcanoes on the Kuril Islands contain hydrothermal systems whose surface manifestations include springs with diversity in their chemical compositions and in their physical and chemical parameters. Thermal waters of Kuril Islands were found to exhibit four main isotopic shifts relative to the local meteoric water line. The ultra-acid Cl–SO4 (SO4–Cl) waters show a

AbstractThis paper provides information on the structure, chemical composition, and concentrations of microelements in ferromanganese crusts and siliceous crusts sampled on the Pervenets Rise, Sea of Japan. The crusts were formed by cementation of small fragments of green clays (celadonite) by manganese hydroxides (todorokite and birnessite) or by silica. The primary process involved the generation

AbstractThis paper reviews high precision measurements of distances by geodimeters and elevations by first-order leveling between permanent geodetic monuments in local strain measurement patches on the coast of the Avacha Bay in order to detect strain precursors of a probable large (М > 7.0) near earthquake and to obtain quantitative characteristics of coseismic strain. We report the results of all

AbstractThis paper reports results from observations of broadband geophysical processes using laser interferometer strainmeters and special acoustic instruments. We demonstrate examples of synchronous recordings of earth strain variations and geoacoustic oscillations of the ground surface in Kamchatka and in the Moscow Region, as well as results from a parallel analysis of these data, showing that

AbstractThe Kamchatka volcanic soils have low concentrations of most chemical elements relative to their general abundances in continental soils and in European volcanic soils. The soils in different areas over the peninsula most typically involve higher bulk compositions of the elements that are typical of intermediate and basic volcanic rocks: Na, Ca, Mg, Cd, Mn, Co, and Cu, and persistently lower

AbstractThis paper presents new data on the age and isotope geochemistry for plateau effusive rocks sampled from the Central Kamchatka Depression and Nikolka Volcano. We have compared these materials with data on rocks sampled in the Klyuchevskaya Group of Volcanoes, as well as from Shiveluch, Kharchinsky, Zarechnyi, Nachikinsky, and Bakening volcanoes, and from an “NEB-adakite” Pliocene shield volcano

AbstractQuantitative estimates of present-day lateral ground surface displacement rates in southern Yakutia were obtained during recent years by setting up the first (and the only so far) stations of continuous GPS observation at the town of Neryungri (NRG) and at the town of Chul’man (CHL3). Both stations are in the southern margin of the Eurasian plate, near the system of active structures that separate