Geodynamic Systems Research Articles

Form of salt rises as an indicator of interaction of geodynamic systems

The forms of salt uplifts are formed under the influence of stresses developing in the earth’s crust and, therefore, can be considered as sensitive indicators of the interaction of geodynamic systems. In the North German basin, in the Cis-Ural trough on the border with the Caspian depression and in the Pripyat trough, under the influ- ence of various sources of stress and deformation, forms of salt uplifts arose, reflecting the superposition of these systems. The mechanisms of such a superposition were both the formation of forms associated with the resulting addition of deformation vectors and the interference of forms associated with each geodynamic system separately.

Structural–Geodynamic Systems of the Eastern Arctic Region

Structural–Geodynamic Systems of the Eastern Arctic Region

Forms of Salt Rises as Indicators of Interaction of Geodynamic Systems

Forms of Salt Rises as Indicators of Interaction of Geodynamic Systems

Modern geodynamic systems of the Urals in relation to seismicity

Modern geodynamic systems of the Urals are studied in connection with the uneven distribution of seismic activity. The neotectonic zoning and geodynamic conditions of its formation in the Southern and Middle Urals and adjacent platform territories were studied in connection with the Katav-Ivanovo mediummagnitude earthquake occurred in 2018. The epicenter was located outside the known zones of possible seismic sources, which required additional research to determine the causes of the earthquake. As a result of near-surface and deep research the Uraltau-Magnitogorsk and Osinsko-Bolsheusinskaya geodynamic systems have been established, which are the cause of the transverse segmentation of the Urals and, possibly, one of the factors of seismic activity. The geodynamic systems are inconsistently articulated with each other with the development of the Birsko-Karatau geodynamically active zone and the Katav-Satka interference zone. The earthquake is associated with the Katav-Satka interference zone. The interference zone has been investigated with respect to fracturing and slickenlines. Orientations of modern stresses induced from the active regions are estimated. Modern stresses are the reason for the activation of the Zilmerdak from the beginning of the Late Paleozoic overstep and, as a consequence, the Katav-Ivanov earthquake. Earthquakes caused the development of secondary dangerous seismogenic phenomena and deformation of buildings.

Fracture Zones of the Doldrams Megatrasform System (Equatorial Atlantic)

This article presents results of the structural and morphological analysis of the fracture zones which are part of Doldrums Megatransform System (MTS), located in the northern part of the Equatorial Atlantic (6.5°–9° N) that include Vernadskiy and Bogdanov transform faults and the Doldrums and Pushcharovskiy megatransforms. Bathymetric map, based on the multibeam echo sounding data, collected during 45 cruise of the R/V Akademik Nikolaj Strakhov was used for this analysis. It was established that large-scale variations in the width of fracture zone valleys are determined by the distribution of stresses perpendicular to the fracture zone. In the areas with compressive stresses, the fracture zone valleys are narrower, and the in extension areas are wider. The difference in geodynamic settings within the MTS is due to the difference in spreading directions, which change from \(\perp \)89° to \(\perp \)93° when moving from south to north. The depth of fracture zone valleys consistently increases from the periphery of the MTS (Bogdanov and Doldrums faults) to the center (Pushcharovskiy fracture zone) in accordance with a decrease in the upper mantle temperature. In each fracture zone, the valley depth decreases from the rift- fracture zone intersections towards the center of the active part to a certain background depth. It is assumed that this phenomenon is the result of the uplift of the valley bottom, which occurred due to the decompaction of the lithosphere, caused by the serpentinization of ultramafic rocks. The violation of the revealed variations in the width and depth of fracture zone valley patterns occurs as a result of various ridges and uplifts formation in the fracture zone. In the axial zones of the active parts of the fracture zone valleys median ridges are widespread, extending parallel to the fracture zone and representing serpentinite diapirs squeezed out above the bottom surface. Transversal ridges which were formed 10‒11 million years ago as a result of the lithospheric plate edge flexural bending under extensional conditions are now located in the western passive parts on the southern sides of the of Doldrums and Pushcharovskiy fracture zone valleys. The transverse ridge on the northern side of the Vernadskiy fracture zone, which includes Mount Peyve, was formed between 3.65‒2.4 Ma. Due to the frequent jumps of the spreading axis in this region, it was divided into three segments. There are interfracture zone ridges in megatransforms, which in the active part consist of two fracture zone valleys. Time of their formation: in Pushcharovskiy megatransform ‒ 30‒32 million years ago and in Doldrums megatransform ‒ about 4 million years ago. Due to the curvilinearity of the outlines and under the pressure of moving lithospheric plates, the interfracture zone ridges experience longitudinal (along the fault) compressive and tensile stresses, which are compensated by vertical uplifts of their separate blocks and the formation of depressions, pull apart depressions, and spreading centers (the latter are only in Pushcharovskiy megatransform). Structure-forming processes that determine pattern and morphology of the fracture zones as a part of the MTS are related by their origin to the spreading and transform geodynamic systems.

Integrated Landsat multispectral imagery and airborne geophysical data for enhanced litho-structural mapping: A case study of Adamawa Massif, north-eastern Nigeria

Landsat-7 ETM + satellite imagery integrated with corrected airborne geophysical data (radiometric, gravity, and aeromagnetic) anomalies maps, and field investigations were used to discriminate lithologies and related structures in Mayo-Belwa and Jada-Ganye-Toungo areas (Adamawa Massif), northeastern Nigeria. Field investigations portray the granite-gneisses as the oldest rock units, and have sequentially been invaded by the syn-, late-to post-collisional Older granites. Subsurface linear structures in the area display dominant NE-SW, NW-SE, NNE-SSW, and ENE-WSW trends, reflective of variations in pre-existing structural orientations, and near-surface expressions of reactivated zones of weakness in the basement crust. The geodynamic systems revealed that most elongated lineaments are expressed as axial part of valleys trending NE-SW, ENE and NNW, forming diagonal grid to the NW-SE stresses. Abnormally high total radioactivity gravitates to areas of deflection (alluvium), and late- and post-tectonic granites. The gravity intensity provides a spectrum of anomalous responses including abnormally high positive gravity (volcanic rocks), moderately high positive gravity (granite-gneisses and late-to post-tectonic and syn-tectonic granites), background gravity and low negative gravity (granite-gneisses, alluvium and proluvium). Aeromagnetic anomalies discriminate the Older granites (intense positive anomalies), granite-gneisses, sediments (moderate positive, near background, and moderate-intensive negative anomalies), syn-tectonic granites (moderate positive anomalies), banded-gneiss and amphibolite (intensive negative anomalies), volcanic rocks (intense negative anomaly), and alluvium/proluvium (low positive anomalies). This present study led to the development of up-to-date and accurate litho-structural and geophysical maps of the geologically-rugged and hardly accessible Adamawa Massif, north-eastern Nigeria and further constrain the geochemical (High-K calc-alkaline, peraluminous) and tectonic (syn-to post-collisional) characteristics of typical Pan-African granitoids.

Influence of structural-geodynamic systems on formation and distribution of hydrocarbon potential of the Black Sea-Caspian region

The article considers the results of the reconstruction and analysis of the geodynamic conditions for the formation of the main elements of their structure in the Black Sea-Caspian region, expressed in the features of the distribution of its structural-geodynamic systems of different ages. As structural-geodynamic systems, sets of elements of the block and zonal structure of the upper part of the earth's crust (basement and sedimentary cover) are considered, united by the same type (general) reaction from an external or internal source of tectonic energy in relation to the system during a certain phase of tectogenesis. The results of the research indicate that the predominantly offshore deep-water Black Sea and South Caspian provinces are controlled by tectonic megadepressions formed in the Alpine and recent epochs of tectogenesis. At the same time, both provinces include in their internal structure both elements that arose at different stages of Alpine and recent structure formation, and fragments of older plate and folded structures, reworked in these epochs and buried under Cenozoic or Cretaceous-Cenozoic deposits, to varying degrees. The latter, in turn, partially or completely control the position and configuration of the oil and gas regions within these provinces. Keywords: structural and geodynamic systems; sedimentary basins of different ages; oil and gas source strata; prospects for oil and gas potential; phase composition; hydrocarbon potential.

Modern structural and tectonic model of the Caspian Region

The article analyzes the development and evolution of the structural and geodynamic systems of the sedimentary complex in the Caspian region, and the results of structural and tectonic modeling of individual tectonic zones in the region. Based on the modeling results, an important feature of the morphology and structure of the basement surface and sedimentary complex in the Caspian Sea is the tracked sea extension of many elements detected on land. The main features of the morphology and structure of the basement surface and sedimentary complex in the Caspian region are the presence of superdeep depressions of the earth’s crust, with the basement depth up to 16 km or more in the North Caspian and up to 20–24 km in the South Caspian, as well as the distinct longitudinal (sublatitudinal) tectonic zonality of the region. Constructed as a result of the implemented reconstructions, the generalized geological and tectonic model of the uneven-aged basement surface comprises the sea and continental parts of the region under study. The study was carried out within the framework of the state contract with Ministry of Science and Higher Education of the Russian Federation, No. 075-00069-20-02, dated September 10, 2020, topic No. AAAA-A20-120092590017-4.

Neotectonic structures and modern geodynamics of the middle flow region of the Don river (the territory of the Novovoronezh nuclear power plant)

Background. Structural and geodynamic studies are conducted in the region of the middle flow of the Don river.Aim. An identification and evaluation of neotectonic structures, determination of geodynamic conditions for their formation and an analysis of intensive exogenous geological processes in connection with the need to ensure the safety of the Novovoronezh nuclear power plant (NPP) located in this area, the largest in the central part of the Eastern European platform.Materials and methods. According to the concept of deep geodynamic systems, the lithological, structural-geomorphological and neotectonic conditions of the territory were studied. Field observations and publications based on geological survey data were the factual material for the studies.Results. Various types of uplifts and troughs, geodynamically active zones and lineaments were identified. The formation of structures is associated with deep (intracortical) stresses of compression and tension, under the influence of which the tectonic-gravity and suffosion-karst processes negative for the territory of the nuclear power plant are activated. Among the ancient Precambrian faults of the crystalline basement, the latitudinal Sudzhen-Ikorets and submeridional Semiluki-Lipetsky faults are active. The latter is considered as a geodynamically active zone. At the NPP site and in its vicinity, the zones of increased fracturing and permeability were identified, which is consistent with the buried forms of the relief — paleo-reliefs of the Don river and its tributaries. These zones are found to be deeply embedded in the Cretaceous and Devonian carbonate rocks, which is the reason for the increased leaching of these rocks and the removal of fine particles from the fluvioglacial strata. A quantitative assessment of summary and step-by-step amplitudes and speeds of neotectonic movements was carried out.Conclusion. The territory of the Novovoronezh NPP is geodynamically calm, the movement speeds (both calculated and according to instrumental measurements) are relatively low; however, these movements activate exogenous processes, which in turn negatively affect the stability of the Novovoronezh NPP site.

Structural–Geodynamic Systems of the Basement of the Black Sea–Caspian Sea Region: Evolution in the Late Paleozoic‒Cenozoic

Structural–Geodynamic Systems of the Basement of the Black Sea–Caspian Sea Region: Evolution in the Late Paleozoic‒Cenozoic

Fuzzy inference systems for mineral prospectivity modeling-optimized using Monte Carlo simulations

This paper uses Monte Carlo simulations to estimate the parameters of rule-based fuzzy inference systems (FISs) designed for mineral prospectivity modeling. The targeted process for the case study is gold mineralization in the Rajapalot project area in northern Finland. Mamdani-type FISs are developed and implemented for the predictive modeling of favorable structural settings and favorable chemical traps causing gold enrichment in host rocks from ore-bearing hydrothermal fluids. The parameters of the fuzzification functions control the output fuzzy membership values. Traditionally these parameters are chosen subjectively based on the expert's domain knowledge. This study uses drill core data statistics to define the distribution of the parameters. Subsequently, Monte Carlo simulations are used to simulate the corresponding fuzzy membership values and optimize the FISs.•Capturing the complexities of the multi-processes geodynamic systems and the possible interplay mineralization-related geological aspects using ‘If-Then’ rule-based fuzzy inference systems.•Implementation of Monte Carlo simulations for quantification of uncertainties related to a Mamdani-type FIS-based prospectivity modeling.•Reporting prospectivity modeling results at different confidence levels for informed decision making on selection of exploration targets.

НЕЛІНІЙНА КОНТАКТНА ДИНАМІКА ТА АНТИСИМЕТРІЯ КОРПУСКУЛЯРНО-ВИХОР-ХВИЛЬОВИХ ФОРМ ЕЛЕКТРОМАГНІТНОГО ТА ГРАВІТАЦІЙНОГО ПОЛІВ У ФОНОВОМУ СЕРЕДОВИЩІ КОМПЛЕКСНОГО ЕВКЛІДОВОГО ПРОСТОРУ. СПЕКТРИ ХІТОННОГО ВИПРОМІНЮВАННЯ

Based on the hydrodynamic-wave calibration of potentials in Maxwell’s equations and their analogues for the gravitational field, nonlinear equations with respect to the vector potentials of these fields in the background medium of a complex Euclidean space are obtained. The nonlinear contact dynamics of corpuscular-vortex-wave forms of fields and violation of antisymmetry, which leads to the formation of matter and generation of electromagnetic, gravitational, hydrodynamic , acoustic waves separately in real and imaginary half-spaces of complex Euclidean space, are considered. Analytical expressions for the spectra of heaton radiation in a complex Euclidean space are obtained. It is shown that these expressions describe, in particular, the spectrum of solar radiation, collider resonance spectra, the spectrum of microwave background radiation generated by the Oort Cloud, and other spectra in technical, space and geodynamic systems. The fundamental technical failures in the field of controlled thermonuclear fusion and the known catastrophes in nuclear energy and hydropower related to the disregard of corpuscular-wave dualism in macrosystems and the limitations of a purely real part of the complex Euclidean space are analyzed.

ОЦЕНКА ГЕОДИНАМИЧЕСКОЙ СИТУАЦИИ ВОРОНЕЖСКОГО КРИСТАЛЛИЧЕСКОГО МАССИВА ПО ГЕОДЕЗИЧЕСКИМ ДАННЫМ

Repeated geodetic measurements allow you to evaluate such geodetic elements as coordinates, heights, and directions. And also represent discretely the field of displacement vectors of geodesic points. The obtained vectors allow us to determine the stress-strain state of the earth's surface according to the accepted model. There is a reasonable opinion about the significant presence of rotational (vortex) movements in geodynamic processes. Here, the corresponding algorithms are used for the territory of the Voronezh Crystal massif. Separately, it is possible to calculate the differential characteristics of the vector field, called divergence (div) and rotor (vortex, rot, curl). The article proposes to determine the rotor field from discrete geodetic observations of displacement vectors on the surface of the studied territory. The most important continuation of this research work is the method of mathe-matical modeling of geodynamic systems for predictive purposes. For the study of complex (nonlinear) geodynamic processes, an appropriate mathematical basis should be chosen. Here, attention is drawn to the involvement of the mathematical foundations of field theory. To evaluate the characteristics of vector fields when using repeated geodetic measurements, the method of finite elements can be used. Dividing the territory under study into triangles allows us to determine the deformation characteristics after calculating the elements of the strain tensor. In particular, the value of the angular velocity of the triangle rotation relative to its center of gravity is found. Next, it is easy to calculate the value of the rotor. The example given in the article of real geodetic observations on the Voronezh crystal massif confirms the possibility of predicting the location of an upcoming seismic event – an earth-quake.

ПРИМЕРЫ ВЗАИМОДЕЙСТВИЯ ГЕОДИНАМИЧЕСКИХ СИСТЕМ В МОРФОСТРУКТУРЕ СЕВЕРА ВОСТОЧНО-ЕВРОПЕЙСКОЙ ПЛАТФОРМЫ

To determine the nature of the contribution of current tectonic processes to the formation of morphostructural ensembles is an important task. This can be done by comparing the morphostructure with the expected consequences of the impact of geodynamic systems. In the border area of the Baltic Shield and the Russian Plate, within the Circumbaltic zone of dislocations, there is a chain of recent graben depressions. The location of the depressions is determined by the tectonophysical patterns of dislocation sampling and favorable local structural conditions. Depression arose as areas of tension with the superpositional interaction of two subordinate horizontally oriented newest geodynamic systems – pressing the Baltic shield onto the Russian Plate and pushing the geological substrate at the point of their junction in the perpendicular direction. In the northern part of the White Sea Depression, the “visor” of the Karelian massif is approaching to the region of oncoming progressive stretching around the Kandalaksha graben. The superposition of these processes is clearly expressed in relief. Thus, the formation of morphostructures in the area is strongly influenced by the interaction of geodynamic systems.

Short-Term Earthquake Prediction: Reality, Research Promise, or a Phantom Project?

The state-of-the-art, obtained results, and possible perspectives of short-term prediction of strong earthquakes are analyzed. Based on examples of specific research it is shown that such prediction with the required detail, accuracy, and reliability has not been carried out as of the present and is not expected to occur in the future. This is a fundamental consequence of the nonlinearity of seismic geodynamic systems that function in deterministic-chaotic manner in the fractal geomedium. The effectiveness of prediction in the form of the ratio between the numbers of successfully predicted and recorded earthquakes within some area is no more than a few percent. Frequent communications about allegedly attained short-term prediction effectiveness of almost 100% are disproven both by the absence of adequate and reliable methods and the steady extension of the list of seismic catastrophes that were not predicted.

The short-term forecast of earthquakes: reality, scientific perspective or the project-phantom?

The modern conditions, the received results and possible prospects of short-term forecasting of strong earthquakes are analysed. On examples of concrete researches it is shown, that such forecast with a required detail, accuracy and reliability is not carried, and is not expected in the future. It is fundamental consequence of nonlinearity of the seismic geodynamic systems functioning deterministically-chaotically in the fractal geologic medium. Effectiveness of forecasting in the form of attitude of number of successfully predicted earthquakes to number of registered ones on some certain area is not above several percent. Frequent messages about ostensibly reached almost 100%-s’ of effective short-term forecasting are denied by absence of adequate reliable methods, and by steady extension of the list of the not predicted seismic catastrophes.

About this title - HP–UHP Metamorphism and Tectonic Evolution of Orogenic Belts

High pressure (HP) and ultrahigh pressure (UHP) metamorphic rocks play a key role in understanding the tectonic evolution of orogenic belts. They have typically experienced complex changes during subduction and exhumation processes arising from recrystallization, deformation, fluid–rock interactions and even partial melting, and may therefore carry valuable records of evolving geodynamic systems in an orogenic belt. This special publication addresses the current work on HP–UHP metamorphism and its relation to the tectonic evolution of orogenic belts. This special publication contains fifteen papers covering the important orogenic belts of the Himalaya, Dabie–Sulu, Tian Shan, North Qaidam and others that have been grouped into three parts: (I) new developments in the determination of metamorphic pressure–temperature (PT) conditions and their timing, (II) overview papers of well-known HP–UHP metamorphic belts and (III) research papers for some newly discovered HP–UHP belts.

HP–UHP metamorphism and tectonic evolution of orogenic belts: introduction

Abstract High pressure (HP) and ultrahigh pressure (UHP) metamorphic rocks play a key role for understanding the tectonic evolution of orogenic belts (Johnson, M.R.W. & Harley, S.L. 2012. Orogenesis: The Making of Mountains . Cambridge University Press, Cambridge). They have typically experienced complex changes during subduction and exhumation processes, arising from recrystallization, deformation, element redistribution, fluid–rock interactions and even partial melting, and may therefore carry a valuable record of evolving geodynamic systems in an orogenic belt. Until now, more than 20 UHP metamorphic belts, i.e. belts which contain rocks that experienced pressure–temperature ( P–T ) conditions exceeding the lower limit of the coesite stability field, have been identified all over the world (Carswell, D.A. & Compagnoni, R. 2003. Ultrahigh Pressure Metamorphism . Eotvos University Press, European Mineralogical Union, Notes in Mineralogy, Budapest; Liou, J.G., Ernst, W.G., Zhang, R.Y., Tsujimori, T. & Jahn, B.M. 2009. Ultrahigh-pressure minerals and metamorphic terranes – the view from China. Journal of Asian Earth Sciences, 35 , 199–231; Zheng, Y.F., Zhang, L.F., McClelland, W.C. & Cuthbert, S. 2012. Processes in continental collision zones: preface. Lithos , 136 , 1–9). New and innovative studies from different geoscience disciplines have been invaluable in developing a better understanding of the geodynamic evolution of orogenic belts. This special issue contains 15 papers, most of which were presented as part of the session ‘HP–UHP metamorphism and tectonic evolution of orogenic belts’, held at the 35th International Geological Congress in Cape Town, South Africa during 27 August to 4 September, 2016.

Legacy sediment erosion hot spots: A cost-effective approach for targeting water quality improvements

A s federal and state governments seek to address nonpoint source (NPS) water pollution, billions of dollars will be spent to implement conservation practices known to reduce sediment and nutrient runoff. Nonpoint source pollution has proven to be a “wicked” challenge for policymakers, characterized by uncertainty and complex interactions among socioeconomic, hydrologic, and other geodynamic systems along multiple dimensions (Shortle and Horan 2017). A recent summary of research indicates, in fact, that the adoption of conventional NPS conservation practices is not directly linked to measurable pollution reduction in most streams in the Chesapeake Bay watershed (Keisman et al. 2018). A primary reason cited for this disconnect is the temporal dynamic by which water quality improvements are delayed or offset by the ongoing effects of legacy pollutants in soils and groundwater (Keisman et al. 2018). (Legacy pollutants are those that remain in the geosphere decades to centuries after the pollution occurred.)Innovative approaches to NPS pollution reduction may be needed to address these legacy pollutants, and thereby meet goals for improved water quality, such as the Chesapeake Bay total maximum daily load (TMDL). One such approach that has received increasing attention is legacy sediment (LS) mitigation. As shown in the research of Walter…

The method of the phase control of the electrical installation during geodynamic monitoring

The paper substantiates the application of the phase control of the multipolar equipotential electrical installation to improve the geodynamic sensitivity of the geoelectric control method in geodynamic and geotechnical monitoring systems. The principle of the control of the source of sounding signals and the detection of geodynamics of the geological environment is shown in article. In this work is proposed the device on base of the phase modulator to eliminate the shortcomings of existing devices of the controlling of the phase of sound geoelectrical signals. The developed device contains two amplitude limiters, the integrating unit, the adder, the master oscillator and the amplitude modulator. In practice the application of the proposed device allow to obtain the technical and the economic efficiency by simplifying of the circuit of the generation of the signal with the phase-modulation, by increasing the linearity of the modulation characteristic, and by generating of the signal with the phase-modulate on output of the device.