12 research outputs found

    ПОЛЕВАЯ ТЕКТОНОФИЗИКА В РЕШЕНИИ ПРОБЛЕМ ГЕОДИНАМИЧЕСКОГО РАЗВИТИЯ ТЕРРИТОРИИ УКРАИНЫ

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    The integrated approach combining kinematic and structural-paragenetic field tectonophysics techniques allows us to construct a continuous time scan of the stress-strain state (SSS) and deformation modes (DM) from sediment lithification to the final orogenic process for the studied areas. Definitions of the continuous sequence of SSS and DM provide for control of the known geodynamic reconstructions and adjustment of geodynamic models. An example is the tectonophysical study of the Alpine structural stage of the Western Mountainous Crimea (WMC) and the Pre-Cambrian complexes of the Ukrainian Shield (USh).Data from WMC allow us to make adjustments to the geodynamic model of the Mountainous Crimea. In particular, trajectories of the principal normal stresses (Fig. 4 and 5), both for shifts and shear faults with reverse components/ normal faults, suggest the reverse nature of movements of the Eastern and Western Black Sea microplates with their overall pushing onto the Crimean peninsula in the south-east, south and south-west (Fig. 7). In the Precambrian USh complexes (Fig. 8), 13 stages of regional deformation are revealed between ≥2.7 and 1.6 billion years ago. Until the turn of 2.05–2.10 billion years, the region was subject to transtension and transpression, as the Western (gneiss-granulite) and Eastern (granite-greenstone) Archean microplates of USh moved to separate from each other in the Neo-Archean and then diverged and converged in the Paleoproterozoic (movements at a sharp angle). It is assumed that in the Archean the Western and Eastern microplates were separated by the oceanic or sub-oceanic lithosphere (Fig. 12, 13). During the period of 2.3–2.4 billion years, the plates fully converged creating a zone of collision. It may be suggested that a possible mechanism for the oceanic window close-up was underthrusting of the upper suboceanic lithosphere layers beneath the crust-mantle plates on gently sloping break-up surfaces (non-subduction option), and one of them is Moho.Spreading of the Western and Eastern microplates of USh began at the turn of 2.05–2.10 billion years, as evidenced by the available tectonophysical data on fields of latitudinal extension of the crust. During spreading 2.1–2.05 billion years ago, emanations and solutions were able to ascend into the upper crust and thus stimulate palingenesis (Novoukrainsky and Kirovogradsky granites), and during repeated spreading 1.75 billion years ago, magma of the basic and acid composition (Pluto gabbro-anorthosite and rapakivi) intruded into the upper crust. The spreading zone coincided with the former collisional suture and became the site wherein the inter-regional Kherson-Smolensk suture was formed; it stretches submeridionally across the East European platform. Комплексный подход, объединяющий кинематический и структурно-парагенетический методы полевой тектонофизики, позволяет строить непрерывную временную развертку напряженно-деформированных состояний (НДС) и деформационных режимов (ДР) изучаемых районов от литификации осадков до завершающего орогенического процесса. Определение непрерывной последовательности НДС и ДР позволяет контролировать уже известные геодинамические построения и корректировать геодинамические модели. Примером может служить тектонофизическое изучение альпийского структурного этажа Западного Горного Крыма (ЗГК) и докембрийских комплексов Украинского щита (УЩ).Данные, полученные в ЗГК, позволяют внести коррективы в модель геодинамического развития Горного Крыма. В частности, траектории главных нормальных напряжений (рис. 4 и 5) как в сдвиговом, так и во взбросовом или сбросовом режимах, указывают на реверсный характер движений Восточно- и Западно-Черноморской микроплит при общем нажиме их на Крымский полуостров с юго-востока, юга и юго-запада (рис. 7). В докембрийских комплексах центральной части УЩ (рис. 8) установлены 13 этапов деформации региона между ≥2.7 и 1.6 млрд лет назад. До рубежа 2.05–2.10 млрд лет назад регион развивался в режиме транстенсии и транспрессии, при котором Западная (гнейсово-гранулитовая) и Восточная (гранит-зеленокаменная) архейские микроплиты УЩ в неоархее расходились, а в палеопротерозое сближались и расходились под острым углом. Предполагается, что Западную и Восточную микроплиты в архее разделяла океаническая или субокеаническая литосфера (рис. 12, 13). В период 2.3–2.4 млрд лет назад плиты сблизились полностью, образовав зону коллизии. Один из возможных механизмов закрытия океанического окна – поддвиг верхних горизонтов субокеанической литосферы под корово-мантийные пластины по пологим поверхностям срыва (несубдукционный вариант), одной из которых является раздел Мохо.На рубеже 2.05–2.10 млрд лет назад начался раздвиг Западной и Восточной микроплит УЩ, который устанавливается тектонофизическими данными по полям субширотного растяжения земной коры. Во время раздвига 2.05–2.10 млрд лет назад эманации и растворы получили возможность подъема в верхнюю кору, стимулируя процессы палингенеза (новоукраинские и кировоградские граниты), а при повторном раздвиге 1.75 млрд лет назад в верхнюю кору интрудировала магма основного и кислого состава (плутон габбро-анортозитов и рапакиви). Зона раздвига совпала с бывшим коллизионным швом и стала местом формирования межрегиональной шовной зоны Херсон – Смоленск, протягивающейся субмеридионально через всю Восточно-Европейскую платформу

    Сейсмічний експеримент TTZ-South

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    The wide-angle reflection and refraction (WARR) TTZ-South transect carried out in 2018 crosses the SW region of Ukraine and the SE region of Poland. The TTZ-South profile targeted the structure of the Earth’s crust and upper mantle of the Trans-European Suture Zone, as well as the southwestern segment of the East European Craton (slope of the Ukrainian Shield). The ~550 km long profile (~230 km in Poland and ~320 km in western Ukraine) is an extension of previously realized projects in Poland, TTZ (1993) and CEL03 (2000). The deep seismic sounding study along the TTZ-South profile using TEXAN and DATA-CUBE seismic stations (320 units) made it possible to obtain high-quality seismic records from eleven shot points (six in Ukraine and five in Poland). This paper presents a smooth P-wave velocity model based on first-arrival travel-time inversion using the FAST (First Arrival Seismic Tomography) code.The obtained image represents a preliminary velocity model which, according to the P-wave velocities, consists of a sedimentary layer and the crystalline crust that could comprise  upper, middle and lower crustal layers. The Moho interface, approximated by the 7.5 km/s isoline, is located at 45—47 km depth in the central part of the profile, shallowing to 40 and 37 km depth in the northern (Radom-Łysogóry Unit, Poland) and southern (Volyno-Podolian Monocline, Ukraine) segments of the profile, respectively. A peculiar feature of the velocity cross-section is a number of high-velocity bodies distinguished in the depth range of 10—35 km. Such high-velocity bodies were detected previously in the crust of the Radom-Łysogóry Unit. These bodies, inferred at depths of 10—35 km, could be allochthonous fragments of what was originally a single mafic body or separate mafic bodies intruded into the crust during the break-up of Rodinia in the Neoproterozoic, which was accompanied by considerable rifting. The manifestations of such magmatism are known in the NE part of the Volyno-Podolian Monocline, where the Vendian trap formation occurs at the surface.Сейсмический профиль TTZ-South с использованием преломленных и отраженных в закритической области преломленных волн, отработанный в 2018 г., пересекает юго-западный район Украины и юго-восточный регион Польши. Профиль TTZ-South был направлен на изучение структуры земной коры и верхней мантии Трансъевропейской шовной зоны (ТЕШЗ) и юго-западного сегмента Восточно-Европейского кратона (склона Украинского щита). Профиль длиной ~550 км (~230 км в Польше и ~320 км на западе Украины) является продолжением ранее реализованных проектов в Польше — профиля TTZ (1993 г.) и CEL03 (2000 г.). Глубинное сейсмическое зондирование по профилю TTZ-South, выполненное с использованием 320 сейсмических станций TEXAN и DATA-CUBE, позволило получить сейсмические записи высокого качества из одиннадцати пунктов взрыва (шесть в Украине и пять в Польше). В данной статье представлена упрощенная Р-скоростная модель, основанная на инверсии времен пробега первых вступлений Р-волн, построенная с использованием программы сейсмической томографии первых вступлений FAST. Полученное изображение представляет собой предварительную скоростную модель, которая состоит из осадочного слоя и кристаллической коры, включающей верхний, средний и нижний ее слои. Поверхность Мохо, аппроксимируемая изолинией 7,5 км/с, расположена на глубине 45—47 км в центральной части профиля, воздымаясь до 40 и 37 км в северной (Радом-Лысогорский блок в Польше) и южной (Волыно-Подольская моноклиналь в Украине) частях профиля соответственно. Особенностью скоростного разреза является ряд высокоскоростных тел, выявленных в диапазоне глубин 10—35 км. Аналогичные высокоскоростные тела ранее были обнаружены в коре Радом-Лысогорского блока. Тела, обнаруженные на глубине 10—35 км, могут быть аллохтонными фрагментами изначально единого массива основных пород или отдельными телами основного состава, внедрившимися в кору в неопротерозое во время раскола суперконтинета Родиния, который сопровождался мощным рифтогенезом. Проявления рифтогенного магматизма известны в северо-восточной части Волыно-Подольской моноклинали, где на поверхность выходят вендские трапы.Сейсмічний профіль TTZ-South з використанням заломлених і відбитих у за критичній зоні заломлених хвиль, відпрацьований у 2018 р., перетинає південно-західний район України і південно-східний регіон Польщі. Профіль TTZ-South був спрямований на вивчення структури земної кори і верхньої мантії Транс'єв ропейської шовної зони (ТЄШЗ) і південно-західного сегмента Східно-Європейського кратона (схила Українського щита). Профіль довжиною ~550 км (~230 км в Польщі і ~320 км на заході України) є продовженням раніше реалізованих проєктів у Польщі — профілю TTZ (1993 р.) і CEL03 (2000 р). Глибинне сейсмічне зондування за профілем TTZ-South, виконане з використанням 320 сейсмічних станцій TEXAN і DATA-CUBE, дало змогу отримати сейсмічні записи високої якості з одинадцяти пунктів вибуху (шість в Україні і п'ять у Польщі). У даній статті представлена спрощена Р-швидкісна модель, що базується на інверсії часів пробігу перших вступів Р-хвиль, побудована з використанням програми сейсмічної томографії перших вступів FAST. Отримане зображення являє собою попередню швидкісну модель, яка складається з осадового шару і кристалічної кори, що включає верхній, середній і нижній її шари. Поверхня Мохо, що апроксимується ізолінією 7,5 км/с, розташована на глибині 45—47 км у центральній частині профілю, здіймається до 40 і 37 км у північній (Радом-Лисогорський блок у Польщі) і південній (Волино-Подільська монокліналь в Україні) частинах профілю відповідно. Особливістю швидкісного розрізу є ряд високошвидкісних тіл, виявлених у діапазоні глибин 10—35 км. Подібні високошвидкісні тіла раніше були виявлені в корі Радом-Лисогірського блоку. Тіла, виявлені на глибині 10—35 км, можуть бути алохтонними фрагментами спочатку єдиного масиву основних порід або окремими тілами основного складу, що впровадилися в кору в неопротерозої під час розколу суперконтінета Родінія, який супроводжувався потужним рифтогенезом. Прояви рифтогенного магматизму відомі в північно-східній частині Волино-Подільської моноклінали, де на поверхню виходять вендські трапи

    ТЕКТОНОФИЗИЧЕСКАЯ ИНТЕРПРЕТАЦИЯ МЕХАНИЗМОВ ОЧАГОВ ЗЕМЛЕТРЯСЕНИЙ СИСТЕМЫ ЗАГРОС

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     Structural-paragenetic and kinematic methods of tectonophysics are applied to study earthquake focal mechanisms of the Zagros system. Nodal planes of focal mechanisms are identified as L-, L′- and R-, R′-shears by the first method, whereby coordinates of principal stress axes P, T and N (i.e. in tectonophysics, σ1, σ3 and σ2, if σ1 ≥ σ2 ≥ σ3) are defined. ‘Working’ nodal planes corresponding to activated ruptures are revealed. Axes of the main normal stresses are combined into local groups on the basis of the kinematic identity of planes of seismogenic ruptures (Figure 2). The second method is applied to construct stereograms of the main axes P, T and N, to construct and interpret stereograms of vectors of seismogenic shifts (Figure 3), and to more clearly define coordinates of principal axes σ1, σ3 и σ2. As evidenced by their comparison, coordinates of the principal axes obtained by the two tectonophysical methods are well coincident (see Figure 2). Five groups of seismogenesis are distinguished; they differ in combination of deformation regimes and kinematic conditions. Locations are determined of the areas wherein earthquake foci of similar parameters are located. This means that seismogenic zones are distinguished; structural and kinematic characteristics of such zones are determined by parameters of stereographic models of corresponding types of seismogenesis (Figures 4 and 5). It is established that the region is dominated by shear and upthrust deformation regimes due to regional submeridional compression and SW-NE compression (see Figures 4 and 5). Submeridional subhorizontal compression is explained by the northward movement of the Arabian plate, and SW-NE compression is explained by divergent processes within the limits of the Red Sea rift. The time pattern of the seismogenic processes from 1979 to 2001 shows that submeridional compression and SW-NE compression are associated with different deep mechanisms. Processes of SE-NW compression, which are observed in the northern part of the Arabian plate, are caused by its interaction with the Eastern Black Sea microplate.   При интерпретации механизмов очагов землетрясений системы Загрос применены структурно-параге­нетический и кинематический методы тектонофизики. Первым методом нодальные плоскости механизмов очагов идентифицированы как L-, L′- и R-, R′-сколы, на основании чего уточнены координаты главных осей напряжений P, T и N (в тектонофизике σ1, σ3 и σ2, при σ1 ≥ σ2 ≥ σ3). Определены «рабочие» нодальные плоскости, соответствующие реальным разрывам. Оси главных нормальных напряжений объединены в локальные группы по признаку кинематической идентичности плоскостей сейсмогенных разрывов (рис. 2). Вторым методом построены стереограммы распределения главных осей P, T и N, построены и проинтерпретированы стереограммы векторов сейсмогенных подвижек (рис. 3) и уточнены координаты главных осей напряжений. Сопоставление координат главных осей, полученных двумя тектонофизическими методами, показало их хорошую сходимость (рис. 2). Обосновано пять типов сейсмогенеза, характеризуемых разными комбинаторными сочетаниями деформационных режимов и кинематических обстановок; локализованы участки размещения очагов со сходными параметрами, то есть выделены сейсмогенные зоны, структурно-кинематическая характеристика которых определяется параметрами стереографических моделей соответствующих типов сейсмогенеза (рис. 4, 5). Установлено, что доминирующими в регионе являются сдвиговый и взбросовый деформационные режимы, обусловленные обстановками субмеридионального и ЮЗ-СВ регионального сжатия (рис. 4, 5). Субмеридиональное субгоризонтальное сжатие объясняется движением Аравийской плиты на север, а ЮЗ-СВ сжатие – дивергентными процессами в пределах Красноморского рифта. Временная развертка сейсмогенных процессов за 1979–2001 гг. показывает, что субмеридиональное и ЮЗ-СВ сжатие связано с разными глубинными механизмами. Процессы ЮВ-СЗ сжатия, фиксируемые в северной части Аравийской плиты, обусловлены ее взаимодействием с Восточно-Черноморской микроплитой. 

    FIELD TECTONOPHYSICS IN SOLUTIONS OF GEODYNAMIC EVOLUTION PROBLEMS OF THE UKRAINE TERRITORY

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    The integrated approach combining kinematic and structural-paragenetic field tectonophysics techniques allows us to construct a continuous time scan of the stress-strain state (SSS) and deformation modes (DM) from sediment lithification to the final orogenic process for the studied areas. Definitions of the continuous sequence of SSS and DM provide for control of the known geodynamic reconstructions and adjustment of geodynamic models. An example is the tectonophysical study of the Alpine structural stage of the Western Mountainous Crimea (WMC) and the Pre-Cambrian complexes of the Ukrainian Shield (USh).Data from WMC allow us to make adjustments to the geodynamic model of the Mountainous Crimea. In particular, trajectories of the principal normal stresses (Fig. 4 and 5), both for shifts and shear faults with reverse components/ normal faults, suggest the reverse nature of movements of the Eastern and Western Black Sea microplates with their overall pushing onto the Crimean peninsula in the south-east, south and south-west (Fig. 7). In the Precambrian USh complexes (Fig. 8), 13 stages of regional deformation are revealed between ≥2.7 and 1.6 billion years ago. Until the turn of 2.05–2.10 billion years, the region was subject to transtension and transpression, as the Western (gneiss-granulite) and Eastern (granite-greenstone) Archean microplates of USh moved to separate from each other in the Neo-Archean and then diverged and converged in the Paleoproterozoic (movements at a sharp angle). It is assumed that in the Archean the Western and Eastern microplates were separated by the oceanic or sub-oceanic lithosphere (Fig. 12, 13). During the period of 2.3–2.4 billion years, the plates fully converged creating a zone of collision. It may be suggested that a possible mechanism for the oceanic window close-up was underthrusting of the upper suboceanic lithosphere layers beneath the crust-mantle plates on gently sloping break-up surfaces (non-subduction option), and one of them is Moho.Spreading of the Western and Eastern microplates of USh began at the turn of 2.05–2.10 billion years, as evidenced by the available tectonophysical data on fields of latitudinal extension of the crust. During spreading 2.1–2.05 billion years ago, emanations and solutions were able to ascend into the upper crust and thus stimulate palingenesis (Novoukrainsky and Kirovogradsky granites), and during repeated spreading 1.75 billion years ago, magma of the basic and acid composition (Pluto gabbro-anorthosite and rapakivi) intruded into the upper crust. The spreading zone coincided with the former collisional suture and became the site wherein the inter-regional Kherson-Smolensk suture was formed; it stretches submeridionally across the East European platform

    Collision processes at the northern margin of the Black Sea,

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    International audienceExtended along the Crimea–Caucasus coast of the Black Sea, the Crimean Seismic Zone (CSZ) is an evidence of active tectonic processes at the junction of the Scythian Plate and Black Sea Microplate. A relocation procedure applied to weak earthquakes (mb ≤ 3) recorded by ten local stations during 1970–2013 helped to determine more accurately the parameters of hypocenters in the CSZ. The Kerch–Taman, Sudak, Yuzhnoberezhnaya (South Coast), and Sevastopol subzones have also been recognized. Generalization of the focal mechanisms of 31 strong earthquakes during 1927–2013 has demonstrated the predominance of reverse and reverse–normal-faulting deformation regimes. This ongoing tectonic process occurs under the settings of compression and transpression. The earthquake foci with strike-slip component mechanisms concentrate in the west of the CSZ. Comparison of deformation modes in the western and eastern Crimean Mountains according to tectonophysical data has demonstrated that the western part is dominated by strike-slip and normal- faulting, while in the eastern part, reverse-fault and strike-slip deformation regimes prevail. Comparison of the seismicity and gravity field and modes of deformation suggests underthusting of the East Black Sea Microplate with thin suboceanic crust under the Scythian Plate. In the Yuzhnoberezhnaya Subzone, this process is complicated by the East Black Sea Microplate frontal part wedging into the marginal part of the Scythian Plate crust. The indentation mechanism explains the strong gravity anomaly in the Crimean Mountains and their uplift

    Some features of the structure of the mantle of the Eastern Mediterranean and their geodynamic interpretation

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    We consider specific velocity anomalies and the corresponding mantle structures of the East Mediterranean-Black Sea-Caspian region. The anomalies are located on latitudinal and longitudinal seismic tomography sections obtained by constructing 3D P-velocity model of Eurasia applying the Taylor approximation method. The depth of the study is of 50—2900 km. The accuracy of determination of the velocity VP is about ± 0.015 km/s. Velocity sections are shown in residual values ΔVP. Physical and mineralogical mantle model of Pushcharovsky was used for the cross sections specification.In the 25—30° E cross sections between latitudes of the 34—48°N high-velocity slabs sinking from the northern edge of the African plate and the southern parts of the East-European plate towards each other are seen. Slabs are connected at a depth of about 600 km in the upper mantle transition zone  in the area of 42—43° N. Below the slabs junction  high-velocity mantle zone thickens and extends to a depth of 1000—1200 km that occurs as a result of slabs relatively high-velocity  material accumulation. From this area down-welling begins which can be traced on latitude sections of 35—45° N as an almost continuous inclined layer of ~1100 km width   and ~ 1900 km length. Down-welling submerges from a depth of 450—550 km at Moesian and Aegean micro-plates area to a depth of 1600—1900 km beneath the East Black Sea, Anatolian micro-plates and the northern part of the Arabian plate. The mechanism of the inclined layer formation is discussed with the involvement of global seismic tomography data, and the numerical simulation performed by L. I. Lobkovsky.In the 42—44° N and 34—36° E sections we trace column type vertical structure, which crosses almost the entire mantle at depths of 50—100 to > 2500 km. In the middle of the column on its axis there is a relatively high-velocity anomaly, which reduces in size and values downward. The shape and structure of the mantle column resembles a "tornado". We consider two possible alternative mechanisms of its formation: a) steep subduction of the West Black Sea micro plate beneath the Central Black Sea Ridge, "wedging" of the mantle and the extension  stresses occurrence  in  border zone I and  middle mantle;  b) rising of the plume from  zone D'',  formation of  extension area in  middle and upper mantle,  lithosphere pulling inward  and  the  subduction zone formation

    Evolution of the stress-strain state and the dynamics of the Skip cover of the Ukrainian Carpathians

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    New results of interpretation of tectonophysical investigations of the flysh deposits in the Skyba nappe of the Ukrainian Carpathians carried out in four areas in its northwestern and central parts are presented. Complex application of structural - paragenetic and kinematic analyses helped to synchronize three parameters - time of deformation, azimuths of the main axes of stresses orientation and deformation modes for prefolding, folding and postfolding stages of development of the outer part of the Ukrainian Carpathians. It has been proved that thrust shear strain was coeval with strike-slip that provided the rapid advancement of the thrust front. The role of normal faulting with о 3 axis stretching of northeastern and northwestern orientations has been shown. It is assumed that the mentioned deformations had relatively young age. Formation of the Skyba nappe structure is related to the development of the Western and Southern Carpathians. In the global scale the activity of the tangential forces of northwestern and sub-longitudinal directions is explained by the convergence of the Adriatic and European microplates and also the African-Arabian and Eurasian mega-plates

    TECTONOPHYSICAL INTERPRETATION OF EARTHQUAKE FOCAL MECHANISMS OF THE ZAGROS SYSTEM

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    Structural-paragenetic and kinematic methods of tectonophysics are applied to study earthquake focal mechanisms of the Zagros system. Nodal planes of focal mechanisms are identified as L-, L′- and R-, R′-shears by the first method, whereby coordinates of principal stress axes P, T and N (i.e. in tectonophysics, σ1, σ3 and σ2, if σ1 ≥ σ2 ≥ σ3) are defined. ‘Working’ nodal planes corresponding to activated ruptures are revealed. Axes of the main normal stresses are combined into local groups on the basis of the kinematic identity of planes of seismogenic ruptures (Figure 2). The second method is applied to construct stereograms of the main axes P, T and N, to construct and interpret stereograms of vectors of seismogenic shifts (Figure 3), and to more clearly define coordinates of principal axes σ1, σ3 и σ2. As evidenced by their comparison, coordinates of the principal axes obtained by the two tectonophysical methods are well coincident (see Figure 2). Five groups of seismogenesis are distinguished; they differ in combination of deformation regimes and kinematic conditions. Locations are determined of the areas wherein earthquake foci of similar parameters are located. This means that seismogenic zones are distinguished; structural and kinematic characteristics of such zones are determined by parameters of stereographic models of corresponding types of seismogenesis (Figures 4 and 5). It is established that the region is dominated by shear and upthrust deformation regimes due to regional submeridional compression and SW-NE compression (see Figures 4 and 5). Submeridional subhorizontal compression is explained by the northward movement of the Arabian plate, and SW-NE compression is explained by divergent processes within the limits of the Red Sea rift. The time pattern of the seismogenic processes from 1979 to 2001 shows that submeridional compression and SW-NE compression are associated with different deep mechanisms. Processes of SE-NW compression, which are observed in the northern part of the Arabian plate, are caused by its interaction with the Eastern Black Sea microplate

    Kinematic evolution of the Pieniny Klippen Belt in Cenozoic (Ukrainian Carpathians)

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    The data on surface, subsurface and deep structure of the Pieniny Klippen Belt (PKB) have been summarized and new results of its geological-structural and fault kinematic studies within the Ukrainian part of the Eastern Carpathians have been presented. In its contemporary appearance as a narrow strongly tectonized zone between the Outer Carpathians and Trans-Carpathian trough PKB was formed in Oligocene—Miocene in the place of ancient ocean. On the surface it is situated within the rootless Pieniny nappe and in the deep it is a steeply dipping deformation zone which developed under compression, simple dextral strike-slip, transtension and transpression. Mesostructures of horizontal shortening and vertical elongation, thrusts and thrust-related folds as well as structures of lateral extrusion — dextral strike-slip along sub-meridional slicken-sides correspond to SW—NE 220° trending compression and correlate with the stage of Alcapa microplate progression in NE direction in Oligocene—Early Miocene. In Early Miocene as a result of counter-clockwork rotation of Alcapa dextral strike-slip deformation is concentrated in boundary zone between Alcapa and accretionary prism of Ukrainian Flysch Carpathians. The stress fields of strike-slip type with orientation of compression axis SE 165—SW 215° and its “rotation” in a zone of simple shear correspond to this stage. Present deformation regime is characterized as transpressure with SW—NE orientation of compression axis

    Tectonophysical and palinspatic sections of the Ukrainian Carpathians along the geo-traverse DOBRE-3 (PANCAKE)

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    Results of tectonophysical studies and palinspatic reconstruction of the Alpine orogene of the Ukrainian part of the East Carpathians carried out along the international profile DSS PANCAKE which intersects southwestern part of East European craton, East Carpathians and the Pannonian basin are under consideration. It has been shown that compression forces of southwest and northwest direction which brought to formation of the Ukrainian Carpathians and detected by corresponding regional paleo-tensions began their activity not later than in late Cretaceous. They were accompanied by right and left shifts of the same direction produced by different velocities of northeastward movement of covers parts and skibs. Reconstruction of balanced section of the Ukrainian Carpathians revealed that the primary width of sediments accumulation basin was not less than 460 km i. e. shortening was 340 km, the volume of orogen denudation was 48,1 %. The Pennine clippe belt belongs to the Pennine cover produced from the sediments of the single Pennine-Marmarosh basin as a part of the Carpathian basin of sediments accumulation
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