An Erratum to this paper has been published: https://doi.org/10.1134/S0742046321030076

Abstract The relationship among the orebody, volcanic rocks, and a rhyolite dike in the large epithermal Kupol deposit (Western Chukotka) is considered. Almost throughout its entire length (more than 3000 m), the orebody of the deposit is intersected by rhyolite dikes. In the studied profiles in the mine excavations at the horizons 425, 455, 470, 515 m, a rhyolite dike clearly intersects and bisects

Abstract This paper reports the first multidisciplinary petrologic, mineralogical, and geochemical studies of the near-crater tephra discharged by the 1669 catastrophic eruption of Etna stratovolcano, Sicily. We studied the grain-size distribution, chemical and mineral-phase composition of the tephra. We determined the composition of trace elements and the composition of encapsulated lithogenic gases

Abstract Lava domes form when a highly viscous magma erupts on the surface. Several types of lava dome morphology can be distinguished depending on the flow rate and the rheology of magma: obelisks, lava lobes, and endogenic structures. The viscosity of magma nonlinearly depends on the volume fraction of crystals and temperature. Here we present an approach to magma viscosity estimation based on a

Abstract The waveforms and spectral content of the earthquakes that were recorded during the period of higher activity on Avachinsky Volcano in 2019 were studied to identify three commonly accepted types of volcanic earthquake (VE), viz., volcano-tectonic, hybrid, and long-period events, as well as a fourth type, a “special” VE type having certain special features in its waveforms. We have identified

Abstract— This paper considers the occurrence, diversity, and special features of volcanic and degassing processes on Titan, as well as analyzing the maximum gas concentrations of volatiles in a vertical profile of its interior and atmosphere. We showed that the specific character of Titan volcanic and degassing processes is due to low temperatures, a peculiar material composition, and the ubiquitous

Abstract Earthquakes with magnitudes Mw = 6.4 and Mw = 7.1 occurred in July 2019, one after the other with an interval of 34 hours, several kilometers apart, near the town of Ridgecrest, Kern County, California, USA. There was a moderate shock with a magnitude of Mw = 5.8 in 1995 in the immediate vicinity of the epicenters of the future earthquakes. A strong earthquake with Mw = 7.4 occurred about

Abstract This paper is an analysis of the seismic process in the source zones of great (M ~ 8) earthquakes occurring at the Pacific seismic belt and in Southeast Asia. We sought to enhance data homogeneity for different seismic regions by proposing the concept of a generalized energy class of earthquakes. The concept is a promising alternative to the existing procedure for the energy classification

Abstract Records of 58 identical broadband seismograph stations were studied made during strong geomagnetic storms. Oscillations of periods of a few hours were studied. These were compared with synchronous variations of earth tides. Anomalous changes in deformation rate were observed after storms at stations installed near continent–ocean boundaries. They lasted a few days and had amplitudes of a few

Abstract This study addresses the possibility of application of the discrete mathematical analysis (DMA) methods to develop algorithms for registration of tsunami occurrences on the basis of routine data of sea level measurements. The algorithms are based on the relationship between the regression derivative and the trend of the record: areas of positive (negative) derivatives correspond to increasing

Abstract The article is devoted to earthquake-prone areas recognition with M ≥ 6.0 in the Caucasus and in the Altai–Sayan–Baikal region. A new approach to the classification of intersections of morphostructural lineaments using the definition of a fuzzy set is proposed. The latter enables an integral interpretation of a single result (composition) of high seismicity zones recognition performed by the

Abstract Studies in archeoseismology were conducted in the Ferghana Valley revealing traces of strong earthquakes that occurred in ancient times. We pointed out in our previous publications that the ancient city of Eilatan perished in the 1st century BC when devastated by a strong earthquake. It was during that time that the capital Farghana (Akhsiket) was damaged. We also detected there a seismic

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