Lithospheric Plates Research Articles

A New View on the Global Redox-Cycle of Biosphere Carbon

The global carbon cycle model is presented as a natural self-regulating machine that provides renewable biomass synthesis during evolution. The machine consists of two parts, geological and biosphere. Between the parts, there is an interaction. The geological part is controlled by the movement of lithosphere plates, which is under the guidance of gravitational forces from celestial bodies acting on the Earth. The movement of the lithosphere plates is divided into a phase of a relatively quick movement, occurring in the tectonically active state of the Earth’s crust, named the orogenic period, and a phase of a relatively slow movement, occurring in the phase of the tectonically quiet state of the crust, named geosynclinal period. In the orogenic period, the energy of moving plates’ collisions is sufficient to initiate sulfate reduction, proceeding in the subduction zone. This is the reaction where sedimentary organic matter is oxidized. Resultant CO2 is injected into “atmosphere—hydrosphere” system of the Earth. Its concentration achieves maximal values, whereas oxygen concentration drops to a minimum since it reacts with the reduced sulfur forms that evolve in the thermochemical sulfate reduction and due to binding with reduced forms of metals, coming to the Earth’s surface with volcanic exhalations. Carbon dioxide initiates photosynthesis and the associated biosphere events. In the geosynclinal period, the sulfate reduction ceases, and CO2 does not enter the system anymore, though photosynthesis in the biosphere proceeds in the regime of CO2 pool depletion. Under such conditions, the surface temperature on the Earth decreases, ending with glaciations. The successive depletion of the CO2 pool results in a regular sequence of climatic changes on the Earth. The ratio of CO2/O2 is the key environmental parameter in the orogenic cycle providing climatic changes. They consistently vary from hot and anaerobic in the orogenic period to glacial and aerobic by the end of the geosynclinal period. The climatic changes provide biotic turnover. Especially abrupt changes accompany the transition to a new orogenic cycle, resulting in mass extinction of organisms and the entry of huge masses of biogenic material into the sediment. This provided the conditions for the formation of rocks rich in organic matter (“black shales”). It is shown that the suggested model is supported by numerous geological and paleontological data evidencing the orogenic cycles’ existence and their relationship with the evolution of photosynthesis.

Results of geophysical research on the Zmiyinyy island

The article presents the results of geophysical observations by the Dnepropetrovsk geophysical expedition «Dneprogeofizika» on Zmiyinyy Island, which performed a full cycle of work from prospecting and surveying studies to providing the island with drinking water.
 In structural and tectonic conditions, the island is considered as the Zmiyinyy insular block of the Danubian horst megablock. The geodynamics of the region is determined by the position and inclination of the collision sutures within the zone of interaction between the Eurasian and African lithospheric plates. Comprehensive geological and geophysical studies included magnetic prospecting, gravity prospecting and electric sounding (Dipole-axial sounding induced polarization DAS-IP) with geological routes along all rock outcrops on the Zmiyinyy island. Detailed integrated geophysical studies were: gravimetric observations over a network of 20×10 m, magnetometric — 10×5 m and electrometric (DAS-IP) — 40×5 m. For the first time on the island, gravimetric stations were set up, which will later become a support for gravimetric surveys. According to the results of magnetic field survey and DAZ-OP electrical exploration observations, an anomalous area was identified, which is perspective for archaeological research. Based on a comprehensive interpretation of geological and geophysical materials, a well was drilled to a depth of 120 m, which confirmed the constructed predictive stratigraphic section of about. Zmiyinyy. Based on the results of the search for sources of drinking water, three wells were drilled, with a fresh water flow rate of up to 10 m3 per day (each). Subsequently, fresh water with minor purification is used as drinking water.

Geodynamics of the Caucasus – Anatolian-Arabian region and Turkey-Syria Earthquakes 2023

The activation of natural disasters in the world requires the development of new approaches to the study of geological processes, in particular, at the boundaries of lithospheric plates, characterized by earthquakes, increased seismicity, volcanism, landslide processes, tsunamis and other dangerous natural processes and hazards. Earthquake of M 7.8 struck south -eastern Turkey and north - western Syria on 6 February 2023. The M 7.8 earthquake is the largest in Turkey since the 1939 Erzincan earthquake, and the second-strongest recorded in the country, after the 1668 North Anatolia earthquake. More than 52,800 deaths were confirmed: more than 46,100 in Turkey, and more than 6,700 in Syria. It is the deadliest natural disaster in Turkey's modern history. The earthquakes caused over US$100 billion in damages. The geodynamic models construction for the deep structure of natural hazards regions is an important contribution to the study of active continental margins, which is necessary for the earthquake forecast, prediction and prognosis, assessing geoecological risks and preparing population actions in the event of natural disasters and catastrophes. The Caucasus - Arabian region is a complex highly-stressed geodynamic structure, characterized by increased heat flow, high seismicity, magmatism and volcanism. The geodynamics of the Caucasus - Arabian region is determined by the collision of the Eurasian and Arabian lithosphere plates, as well as the complex history of the development of the Alpine-Himalayan belt and surrounding territories. The problem solution of geological structures formation and evolution in various complex geodynamic settings and natural hazards forecast and prognosis requires an analysis of all available geological - geophysical data, as well as the formulation and solution of problems of mechanical and mathematical modeling. Slow lithospheric deformations are simulated by models of viscous flow in multi-layered, incompressible, high-viscosity Newtonian fluid, using Navier-Stocks equation and discontinuity equation. The solution of the inverse problem of geodynamics by the direct method is developed. The first inverse problem of geodynamics was solved - the restoration of the velocity fields, pressures and stresses at the depth of the lithosphere according to the available data on the velocities on the surface. The second inverse problem of geodynamics has been posed and solved - the determination of the movement of boundaries at the depth of the lithosphere based on the given movements of the surface. The solutions obtained can be used to analyze deep geodynamic problems, and together with geothermal modeling, geological and geophysical methods and seismic tomography can serve as a reliable apparatus for studying deep geodynamics due to the formation and evolution of geological structures and the lithosphere stress-strain state researches. The solution of the problem is analyzed on the example of the Caucasus - Arabian region geodynamics. The Geodynamic concept of geoenvironment has been developed. Geodynamic models of the regions of hazardous natural processes in order to predict and prevent natural disasters and catastrophes are constructed. An algorithm for creating monitoring systems is suggested.

Thermomechanical modelling of lithospheric slab tearing and its topographic response

Lithospheric slab tearing, the process by which a subducted lithospheric plate is torn apart and sinks into the Earth’s mantle, has been proposed as a cause for surface vertical motions in excess of 100 s of meters. However, little is known about the mechanisms that help initiate and control the propagation of slab tearing and the associated uplift. This study aims to explore these processes by means of 3D thermo-mechanical geodynamic modelling of a slab retreat oblique to a continental margin, using the Gibraltar Arc region (Betic Cordillera) as a scenario for inspiration. Our results suggest that the obliquity of the continental passive margin relative to the subduction trench leads to an asymmetric distribution of subduction forces and strength, facilitating the initiation of slab tearing. The model results predict a lateral migration of the tearing point at a velocity ranging between 38 and 68 cm/yr for a sublithospheric-mantle viscosity of up to 1e+22 Pa s. This fast slab tearing propagation yields uplift rates of 0.23–2.16 mm/yr above the areas where the subducted slab is torn apart, depending on mantle viscosity. Although a more detailed parametric exploration is needed, this range of uplift rates is compatible with the uplift rates required to overcome seaway erosion along the Atlantic-Mediterranean marine corridors during the Late Miocene, as proposed for the onset of the Messinian Salinity Crisis.

Models of plate tectonics with the Lattice Boltzmann Method

Modern geodynamics is based on the study of a large set of models, with the variation of many parameters, whose analysis in the future will require Machine Learning to be analyzed. We introduce here for the first time how a formulation of the Lattice Boltzmann Method capable of modeling plate tectonics, with the introduction of plastic non-linear rheology, is able to reproduce the breaking of the upper boundary layer of the convecting mantle in plates. Numerical simulation of the earth’s mantle and lithospheric plates is a challenging task for traditional methods of numerical solution to partial differential equations (PDE’s) due to the need to model sharp and large viscosity contrasts, temperature dependent viscosity and highly nonlinear rheologies. Nonlinear rheologies such as plastic or dislocation creep are important in giving mantle convection a past history. We present a thermal Lattice Boltzmann Method (LBM) as an alternative to PDE-based solutions for simulating time-dependent mantle dynamics, and demonstrate that the LBM is capable of modeling an extremely nonlinear plastic rheology. This nonlinear rheology leads to the emergence plate tectonic like behavior and history from a two layer viscosity model. These results demonstrate that the LBM offers a means to study the effect of highly nonlinear rheologies on earth and exoplanet dynamics and evolution.

To the study of the vibration in an acoustic medium with coating excited by a concentrated harmonic source

When monitoring dangerous geodynamic processes, it is topical to study wave fields on the surface of geological structures and, since on the scale of the Earth’s structure, lithospheric plates can be considered as coatings of small thickness, a plate is accepted as the simplest model of an extended lithospheric one. The paper considers the problem of the plate oscillations on the surface of an acoustic layer, excited by the effect of a concentrated harmonic source located in an acoustic medium. The solution is built using an integral approach well developed for similar problems arising in geophysics, seismoacoustics and ecology. Integral representations of the amplitude values for the stress on the lower boundary of the coating and the surface displacements of the structure under consideration are obtained.

AGE AND TECTONIC SETTING OF THE KOPRI-TYPE GRANITOIDS OF THE JUNCTION ZONE OF THE DZHUGDZHUR-STANOVOY AND WEST-STANOVOY SUPERTERRANES OF THE CENTRAL ASIAN FOLD BELT

Geochemical, geochronological (U-Pb on ID TIMS zircons), and isotope-geochemical (Sm-Nd) studies of the Kopri-type granitoids of the Tukuringra Complex have been done. The granitoids localized exclusively in the zone of the Dzheltulak suture, which separates the Dzhugdzhur-Stanovoy and West Stanovoy superterranes of the Central Asian fold belt. It has been established that they can be classified as postcollision granitoids of elevated alkalinity and basicity of the adakite type, formed in the age range of 127 ± 1–126 ± 1 Ma, which are part of the Late Mesozoic postcollision Stanovoy volcano-plutonic belt extending in the sublatitudinal direction from the Sea of Okhotsk inland continent subparallel to the Mongolo-Okhotsk suture zone for more than 1000 km and stitching the Dzhugdzhur-Stanovoy and West- Stanovoy superterranes. The structural position of massifs of the Kopri-type granitoids fixes the upper age boundary of the formation of the Dzheltulak suture. The formation of the initial magmas of these granitoids is connected with an essentially lithospheric source formed as a result of mixing of the Early Precambrian and younger, apparently, Phanerozoic component. The similarity in the Nd isotopic composition of the granitoids of the Kopri-type with similar in composition and age granitoids of the West Stanovoy superterrane most likely indicates the similarity of their sources, as well as the fact that the Dzheltulak suture zone “plunges” in the northeast direction under the structures of the Dzhugdzhur–Stanovoy superterrane. This is in full accordance with modern ideas about the features of the deep structure of the junction of the Eurasian and Amur lithospheric plates.

Ductile Deformation of the Lithospheric Mantle

The strength of lithospheric plates is a central component of plate tectonics, governed by brittle processes in the shallow portion of the plate and ductile behavior in the deeper portion. We review experimental constraints on ductile deformation of olivine, the main mineral in the upper mantle and thus the lithosphere. Olivine deforms by four major mechanisms: low-temperature plasticity, dislocation creep, dislocation-accommodated grain-boundary sliding (GBS), and diffusion-accommodated grain-boundary sliding (diffusion creep). Deformation in most of the lithosphere is dominated by GBS, except in shear zones—in which diffusion creep dominates—and in the brittle-ductile transition—in which low-temperature plasticity may dominate. We find that observations from naturally deformed rocks are consistent with extrapolation of the experimentally constrained olivine flow laws to geological conditions but that geophysical observations predict a weaker lithosphere. The causes of this discrepancy are unresolved but likely reside in the uncertainty surrounding processes in the brittle-ductile transition, at which the lithosphere is strongest. ▪ Ductile deformation of the lithospheric mantle is constrained by experimental data for olivine. ▪ Olivine deforms by four major mechanisms: low-temperature plasticity, dislocation creep, dislocation-accommodated grain-boundary sliding, and diffusion creep. ▪ Observations of naturally deformed rocks are consistent with extrapolation of olivine flow laws from experimental conditions. ▪ Experiments predict stronger lithosphere than geophysical observations, likely due to gaps in constraints on deformation in the brittle-ductile transition.

Basin formation, magmatism, and exhumation document southward migrating flat-slab subduction in the central Andes

The Central Andean Plateau is the largest plateau formed in a non-collisional setting and is taller, wider, has thicker crust, and has greater retroarc shortening than any other region of the modern Andes. It also hosts some of the thickest Cenozoic strata in the Andes, which were deposited synchronously with punctuated widening and narrowing of the magmatic arc. Multiple hypotheses have been advanced to explain these unique characteristics, yet the detailed, plateau-scale Cenozoic basin history needed to test these hypotheses remains unavailable and therefore has not been integrated into the established records of deformation and magmatism. Here we synthesize new detrital zircon maximum depositional ages (MDAs) and sediment provenance analysis of non-marine strata from ∼15°–16.5°S with existing records of sediment accumulation, deformation, and magmatism from ∼14°–24.5°S to develop a model of the Eocene–early Miocene evolution of the Altiplano-Puna plateau region. Stratigraphic correlations based on the new MDAs show a Paleocene–Eocene unconformity/condensed section followed by resumption of rapid sediment accumulation. Rapid sediment accumulation resumed at 46–43 Ma at 15–16°S, at 36 Ma at 18°S, and as young 19 Ma at ∼23°S. Provenance data presented herein indicate that Eastern Cordilleran detritus appeared in Altiplano strata at progressively younger ages to the south. The southward progression of this basin reorganization proceeded in lockstep with initiation of exhumation in the Eastern Cordillera, and also a lull in the magmatic arc followed by widespread volcanic flare-up. We present a model in which the observed stratigraphic hiatus, along with the magmatic lull and flare-up, orogenic widening, and high-magnitude shortening, are upper plate responses to shallowing and resteepening of an late Paleocene–early Miocene flat slab beneath the Altiplano-Puna plateau. In the proposed model initial slab flattening was driven by late Paleocene–early Eocene subduction of buoyant oceanic crust: potentially a Manihiki Plateau Conjugate. Subsequently, southward shallowing and resteepening of a late Eocene–early Miocene flat slab beneath the Altiplano-Puna Plateau was driven by subduction of an asperity on the Nazca Plate which we tentatively identify with the Juan Fernandez Ridge. The geographic coincidence of all of these features suggests that the flat slab hydrated and weakened the upper plate lithosphere, thereby facilitating later development of the suite of unique features which characterize the Central Andean Plateau.

Исследование величины аномалий теплового потока в тылу зон субдукции в зависимости от угла и скорости субдуцирующей плиты

The relevance of the material presented in this article is related to the identification of the dependence of the anomalous heat flux magnitude on the angle and velocity of lithospheric subduction, and assuming the constancy of the effective viscosity of the upper mantle material and the conductive mechanism of dissipative heat transfer. We analytically solved the equation of dissipative heat transport in a mantle wedge over a flatly subducting lithospheric plate on the basis of the method estimating the anomalous heat flux carried to the day surface from the mantle wedge in the rear of subduction zones. As a result, exemplified by Amur and Adriatic plates, for which the velocity of subduction is determined by modern geodetic methods (approximately 10 mm per year) and the angle of subduction — from seismological data (25–30 degrees), the obtained dependence of the anomalous heat flux on the angle and velocity of lithospheric subduction is proved valid. The previously unmeasured velocity of the Black Sea microplate subduction under the Crimea was estimated of 3 mm per year. With the obtained velocity of matter in the mantle wedge at the roof of the mantle, the upward conductive flow can provide the observed removal of heat and hydrocarbons from the mantle to the day surface and the formation of hydrocarbon deposits.

ГЕОДИНАМИКА И ИСТОРИЯ ФОРМИРОВАНИЯ ОКРАИННЫХ МОРЕЙ ЗАПАДНОЙ ЧАСТИ ТИХОГО ОКЕАНА КАК ВИХРЕВЫХ СТРУКТУР

In the tectonic structure of the Earth, formed by rotational processes, a stable regmatic network (tectonic framework) and structures of the central type (ring, vortex, etc.) are of the main importance. Lithosphere plates are global vortex systems arisen as a result of the tectonic flow of masses in the state of a viscous fluid. Eddy structures are tectonic complexes in which the results of vertical and horizontal tectonic movements combination are captured and can be recorded by direct geological observations. In the Western Pacific Ocean, it is noteworthy a series of structures in the form of a system of marginal seas representing the Western Pacific continent-ocean transition zone. The tectonic evolution of the West Pacific region is the formation of lithosphere eddies series in the continent-ocean junction zone. It is associated with the Earth mantle and upper shells (tectonospheres) energy interaction, due to the unstable regime of the planet’s rotational dynamics. Of particular interest are the global shear zones and eddies of the lithosphere formed as a result of horizontal and vertical tectonic movements combination. It is shown that: 1) all tectonic dislocations contain both horizontal and vertical components of the movement velocity, the former dominating in the structure formation of the region; 2) their interaction outcome is vortex and other nonlinear deformations of the lithosphere, which constitute the main type of structural elements of the region; 3) they are often accompanied by the tectonosphere magmatic activation in the form of convective movements and / or plumes “floating”; 4) the Western Pacific marginal-sea depressions are the funnels of convective cells, which formed lithosphere eddies under the conditions of a shift in the interacting lithosphere plates velocities.

ПОСТРОЕНИЕ СКОРОСТНОЙ МОДЕЛИ ВЕРХНЕЙ ЧАСТИ ЗЕМНОЙ КОРЫ ЗОНЫ СОЧЛЕНЕНИЯ ЕВРАЗИЙСКОЙ И ОХОТОМОРСКОЙ ПЛИТ ВДОЛЬ СЕВЕРО-ВОСТОЧНОГО УЧАСТКА ПРОФИЛЯ 3-ДВ ПО РЕЗУЛЬТАТАМ ЦИФРОВОЙ ОБРАБОТКИ ДАННЫХ ПРОДОЛЬНЫХ И ПОПЕРЕЧНЫХ ПРЕЛОМЛЕННЫХ ВОЛН

An automated algorithm for monitoring the areas of refraction event tracking along the profile based on the dynamic conversion method is developed. Time sections of compressional - and shear-wave refractions recorded by the CDP shooting geometry on the North-Eastern segment of the 3DV survey base line are constructed. A high-speed model of the upper part of the Earth’s crust is constructed to depths of ≈2 km in the conjunction zone of the Okhotsk and Eurasian lithospheric plates. According to increased values of the velocity ratio of P- and S- waves, it is found that refracting boundaries in the Ayan-Yuryakh block are sections of rocks with various lithological composition in sedimentary cover. The zone of reduced values of P-wave velocity and the VP /Vs ratio associated with a high fragmentation of rocks is identified on the high-velocity profile of the Chay-Yurya fault zone, both above and below the refracting boundary. The velocity values of P- and S-waves (6.0–6.1 km/s and 3.6–3.7 km/s, respectively,) and reduced values of the Vp /Vs ratio (≈1.65) concerned with intrusions of acid rocks were recorded in the southern part of the Inyali-Debin block within t he depth range of 1–1.5 km.

ВПЛИВ ГЛОБАЛЬНОЇ СЕЙСМІЧНОЇ АКТИВНОСТІ НА ПАРАМЕТРИ ІОНОСФЕРИ ТА ПРИЗЕМНОЇ АТМОСФЕРИ

Subject and Purpose. The catastrophic magnitude of life and monetary losses associated with earthquakes spurs extensive searches for reliable earthquake precursors. It is common knowledge that lithospheric processes have a direct bearing on the state of atmosphere and ionosphere during earthquakes. However, the usual practice is to enquire things in the immediate vicinity of the hypocenter, notwithstanding the global nature of seismic processes. The present work is different as considers the changes of pressure and temperature in the near-Earth atmosphere and the total electron content (TEC) in the ionosphere for world regions at arbitrary distances from hypocenters of strong earthquakes. Methods and Methodology. Employed are the data from the maps of the ionospheric TEC and the maps of the pressure and temperature in the atmospheric surface layer in world regions of 40°N latitude. The quantitative estimates are provided by the superposed epoch analysis for winter seasons between 2012 to 2018. Days of strong earthquakes of the Richter magnitudes within 6.3 to 7.9 are taken for the "zeros" whatever the geographical coordinates of the event. Results. The near-Earth atmosphere pressure P0 shows a decrease for about 5 days before the earthquake and gets elevated for about 5 days after the event. The air temperature T behaves in the opposite way. The TEC shows a sharp increase 2 to 5 days before the earthquake. The typical deviations DP0 and DT are of up to 2 hPa and 0.3 K, respectively. The TEC deviations, DTEC, are within 3 to 4%. Where the longitudes fall on the lithosphere plate boundaries, these deviations are nearly doubled. Also, the magnitude of the effect is higher in the regions where the atmospheric pressure is lower. The established patterns indicate that the gas release from underground plays an important role in the lithosphere-atmosphere and lithosphere-ionosphere interaction effects. In this case, the main part is played by radon fluxes that initiate the near-Earth atmosphere ionization and trigger a whole chain of secon- dary processes. Conclusions. The results of the work indicate that atmospheric and ionospheric effects caused by lithospheric processes take place at arbitrary distances from strong earthquake hypocenters. Gaseous emissions from underground play an important role as a primary factor of these global effects.

ТЕПЛОВОЙ ПОТОК И РЕОЛОГИЧЕСКОЕ РАЗУПЛОТНЕНИЕ КОРЫ И ВЕРХНЕЙ МАНТИИ В РИФТОГЕННЫХ И ПЛЮМОВЫХ СТРУКТУРАХ НА ВОСТОЧНОЙ ОКРАИНЕ АЗИИ

Results of the correlation analysis of heat f low anomalies (Q) with distributions of density contrast ( -parameter) in rifting and plume structures on eastern margin of Asia are considered, which prove selective inverse correlation of these parameters in depth intervals corresponding to the position of the subcrustal viscous layer and asthenosphere. Rifting structures are characterized by ruptures in rigid layers displayed by maxima of the  -параметра, while plume-type central structures are characterized by concentrically zonal distribution of density contrast. The main contribution to the thermal anomalies in rifts is made by the subcrustal viscous layer. Thermal flow from the asthenosphere at the Ceinozoic boundaries of lithospheric plates is screened by subducting slabs. The identical correlation of Q and  -parameter in distant regions testifies to the same deep structure and universality of tectonic regimes on the eastern margin of Asia, where subduction, rifting and plume processes are coupled in space and time.

STATISTICAL ANALYSIS OF GEOLOGICAL AND GEOPHYSICAL PARAMETERS OF THE MONGOLIAN-BAIKAL REGION

The origins and formation mechanisms of neotectonic structures in a part of the Mongolian-Siberian region were identified by geodynamic zoning based on multidimensional statistical analysis of numerical arrays describing geological-geophysical and geological-geomorphological processes. These processes in the regional lithosphere were described by a set of 11 geological and geophysical parameters, divided into three main groups using the hierarchical method of cluster analysis. The first group includes the seismic moment, the density of active faults, the rates of current horizontal deformations, and the magnitude of the deep heat flow. The second group involves the thicknesses of the earth’s crust and exogenous active layer, the velocities of current horizontal movements, and the amplitudes of vertical neotectonic movements. The third group includes gravity anomalies and the lithosphere thickness. The spatial grouping of parameters by cluster analysis (K-means method) yields seven clusters, whose spatial position and composition are determined by the geological history, geological structure, geodynamic evolution of the region, and the current deformation rates. Some clusters characterize large rigid lithospheric blocks, while other clusters describe large active fault systems in the given area. The search for latent factors that make the greatest contribution to the dispersion of the geological and geophysical parameter values was carried out using the principal component method, which makes it possible to minimize the number of factors. Four main factors were identified for areas that differ in the morphology and origin of neotectonic structures: (i) higher horizontal compressive and tensile strains, (ii) dynamic effect of mantle anomalies, manifested in uplifts and arching, (iii) activation of thinned lithosphere within the boundaries of lithospheric plates and large blocks, and (iv) active shear deformation of the earth’s crust. The results of clustering and factor analysis of numerical arrays describing the geological-geophysical and geological-geomorphological processes within the Mongolian-Siberian region can be interpreted in the framework of physical mesomechanics.

Корреляция геологических комплексов горного массива Хан-Тенгри в пограничных районах Кыргызского, Казахского и Китайского Тянь-Шаня

Researchers of the border regions in Kyrgyzstan, Kazachstan, and China discuss two two alternative models for the relationships between the main structural units of the Tianshan mountains. Most researchers believe that the Kyrgyz Middle Tianshan wedges out to the east along the Atbashi-Inylchek-Nalati marginal fault. According to another hypothesis, the Middle Tianshan structures continue within the range Nalati where they are described as Chinese Central Tianshan. Comparing the characteristics of the Paleozoic and Proterozoic sedimentary, volcanogenic, intrusive, and metamorphic formations of these regions leads us to the conclusion that the structural units of the Kyrgyz Middle and most of the Northern Tianshan, including the superimposed Middle-Late Paleozoic troughs, are not continued into China, but are successively cut along the echelon system of conjugated strike-slip faults, united by us into the Frontal Tianshan Dextral Strike-slip (FTDS). And only the northern segment of the Issyk-Kul terrane can be considered as an analogue of the Chinese Central Tianshan, displaced along the FTDS to the northwest for a distance over 80 km. Therefore, adjacent geological complexes are eroded along the FTDS similar to the oblique boundaries of convergent lithospheric plates affected by tectonic erosion.

“The Anger of a Deity Dwelling in a Mountain”: the Specific Aspects of the Perception of Volcanic Eruptions in the Heian Japan

Volcanic eruptions, hurricanes and earthquakes are the most powerful forces on Earth. Scientists are trying to understand these dangerous phenomena, however, despite the increasing dominance of man over nature, they still confuse, frighten and depress human minds. Every year, volcanic activity (about 60 eruptions a year), typhoons and earthquakes cause destruction in many parts of the world and bring death to living beings. Most volcanoes are located in the zone of the Pacific Ring of Fire: a region around the rim of the Pacific Ocean, where lithospheric plates collide and form breaks, from which molten magma flows upward. Thick magma filled with gases provokes explosive eruptions. In ancient times, in different parts of the world, and Japan is no exception, natural disasters caused superstitious fear, and also were the object of admiration and religious worship. Despite the fact that natural anomalies in ancient and medieval Japan caused anxiety, they were also often seen as a foretoken of future misfortunes that could bring discord into the normal way of life. In those distant times, the natural and social orders were perceived as interrelated phenomena, and not a single unusual phenomenon of nature could remain undiscovered. In case of any manifestations of natural disorder, it was necessary to prevent or weaken any likely adverse consequences with the help of various prohibitive regulations as well as magic and ritual actions. This article is devoted to the specific perception of volcanic eruptions in the Heian era (mainly in the 9th century). In the conditions of numerous eruptions in at the territory of the Japanese archipelago and the inability to focus on Chinese political texts due to not so high volcanic activity in China, the Japanese political elite had to create their own algorithm for interpreting the causes of volcanic eruptions, which was based on native Japanese beliefs, where mountains were revered as sacred objects and often perceived as the abode of deities. The study is based on historical sources of various types: chronicles (“Nihon koki”, “Shoku Nihon koki”, “Nihon sandai jitsuroku”, “Nihon kiryaku”) and collections of act material (“Ruiju sandaikyaku”), as well as research literature, mainly in Japanese.

Penerapan Business Intelligence Untuk Menganalisa Data Gempa Bumi di Indonesia Menggunakan Tableau Public

One of the natural disasters that often occurs in Indonesia is an earthquake. This is because Indonesia's geological position is between 3 important lithospheric plates, namely the Pacific, Eurasian and Indo-Australian plates. The forces between the plates are constantly changing, dampening disturbances both on land and at sea. This study aims to focus on visualizing earthquake data in Indonesia and implementing Business Intelligence to display earthquake area data, depth and magnitude. The method of this study uses the Tableau Public platform to process earthquake datasets in Indonesia obtained through www.kaggle.com for the period 01 January 2018 to 30 September 2022. This research produces a report in the form of a dashboard that contains data visualization for the earthquake area, depth and magnitude from various regions in Indonesia that can be used to assist in decisions to be taken. Various designs for dashboards can be used in Tableau to make data easier to read and understand.

SEISMICITY of YAKUTIA in 2016–2017

According to the data of 23 seismic stations of the Yakutia branch of GS RAS, the seismicity monitoring of the territory of the Republic of Sakha (Yakutia) was carried out for 2016–2017. During this period, more than 800 earthquakes with an energy class of KR≥7.1 (magnitude M≥1.7) were registered. This is somewhat more than in 2015 (N=567) and is due to the extension of the time interval of work up to 2 years. The epicenters were located in the zones of interaction between large lithospheric plates: the Eurasian and North American in the Northeastern and Arctic regions, as well as the Eurasian and Amur in the southern regions of Yakutia. The clusters of these events comprised two extended (Arctic-Asian and Baikal-Stanovoy) seismic belts. On the map of epicenters, these zones are displayed as a continuous strip of earthquakes from the Olekma River to the Sea of Okhotsk in the south and in the form of separate groups and clusters of earthquakes between the Laptev and Okhotsk Seas – in the northeast and in the Arctic. The highest seismic activity was noted in the Olekma area, the Stanovoy Ridge and the Aldan Highlands (Southern Yakutia) and the Chersky Ridge and Laptev Sea (in the North-East). Information on the manifestations of local seismicity in the Lena River Delta, where from August 2016 to December 2017 is given. 25 temporary field automatic stations under the joint Russian-German project "Seismicity and neotectonics of the Laptev Sea region" (SIOLA) in 2016–2018 operated. The first results of the distribution of Arctic earthquakes in the lower reaches of the Lena River in space, time, by depth and their connection with active tectonics are considered.

Late Miocene to recent tectonic evolution of the Macquarie Triple Junction

Abstract The Pacific, Antarctic, and Macquarie lithospheric plates diverge from the Macquarie Triple Junction (MTJ) in the southwestern Pacific Ocean, south of Macquarie Island. Morphobathymetric, magnetic, and gravity data have been used to understand the evolution of the three accretionary/transform boundaries that meet at the MTJ. Plate velocities, estimated near the MTJ and averaged over the past 3 m.y., indicate an unstable ridge–fault–fault triple junction. The long life (>6 m.y.) of this configuration can be attributed to a rapid increase in spreading asymmetry along the Southeast Indian Ridge segment as it approaches the MTJ, and to transtension along the southernmost strand of the Macquarie–Pacific transform boundary. A major change in plate motion triggered the development of the Macquarie plate at ca. 6 Ma and makes clear the recent evolution of the MTJ, including (1) shortening of the Southeast Indian Ridge segment; (2) formation of the westernmost Pacific-Antarctic Ridge, which increased its length over time; and (3) lengthening of the two transform boundaries converging in the MTJ. The clockwise change of the Pacific-Antarctic motion (ca. 12–10 Ma) led to complex geodynamic evolution of the plate boundary to the east of the triple junction, with fragmentation of the long-offset Emerald transform fault and its replacement over a short time interval (1–2 m.y.) with closely spaced, highly variable transform offsets that were joined by short ridge segments with time-varying asymmetries in the spreading rates.