Geological structure

Jan 24, 12 Geological structure

The territory of Kyrgyzstan is geologically unique place on the Eurasian continent, as only here, as a result of counter-movements, the collision folded belts of the world's largest. Tenir Tooskaya part of the country is composed of Paleozoic complexes of the Urals – the Mongolian fold belt and structural features are due to the HN-cerned the movement of the lithosphere, mainly from north to south, and Pamir – complexes of the Alpine-Himalayan fold belt, the structure of to-cerned formed lithosphere moves Ry mainly from south to north. Meeting of the structures of these zones is in the valley of the Chon-Alai. Immediately after leaving the west and east, the structure of these zones and strongly diverge sharply away from each other. In the geological components of the country is positive nodal mapping the structure of Eurasia, it is like a bridge connecting east and west, and is essential in solving many problems of regional geo ogy.

On the territory of the country divided into the following major tectonic pulse stretched zones: Northern, Middle and South Tenir Too and Northern Pamirs. In the eastern limits. tion of the South Tenir Too Kakshaalskogo ridges to the east one is a small part of the Tarim massif. The boundaries of these structures are the major regional faults tional crust. North and Middle Tenir Too restricted a fault, the so-called Major structural line Tenir Too, Middle and South Tenir Too reserves to de – South Fergana-Babashatinskim on perceived current – Atbashi-Enilchekskim faults, South HYDRATED Tenir Too limited to the south of Hissar-As-shaalskim fault to -ing on the west separates it from the North Pamirs in the east – from the Tarim massif. The Middle and Southern Tenir Too divided into app. and east. tional sector of the diagonal of the Talas-Fergana shift. The western sector offset on it in the north-west by 180 – 250 km east relative. sectors.

The geological structure of the territory of the republic of the public are four mega and the corresponding four megaetapa TII in the development of the lithosphere to-rye drastically different composition, structure and terms of their formal valuations. From the ground up is Archean-nizhnepro terozoysky, Proterozoic, Paleozoic verhneprotero zoysko-and Mesozoic-Cenozoic mega. The first and third of these geological formations of addition HN, formed in the bathrooms of continental and oceanic dynamic geometry environments, and the second and fourth th – formations only to continental environments. Learn more about angling direct.

Archean-Lower Proterozoic mega presented extensively metamorfizirovanny mi entities to-rye make up the individual blocks, the core of the Paleozoic tectonic uplift and base rigid arrays within the Northern and Middle Tenir Too, and Tarim blocks of the array. Its structure has two groups of entities: a) the ophiolite complexes tovye – some combination of al trabazitov, amphibolized litsitov mafic and b, which are canonical ocean crust rocks and b) the gneisses, schists and marbles – primarily sedimentary thick soup, the deposition of a-ryh happened in the continental crust experimentally. Breed of a thrust upon the rock group b, they are subject to strong folding, deformation flow, resulting in many cases very mixed. Breed also experienced metamorphism and ICSG tizatsiyu. Radiometric studies established the date of 2600 ± 50 Ma and 2000 – 1800 Ma.

The nature of the rocks indicates that in those times there were already continental and oceanic structures, and later, conflicts result in the re framing the continental masses, there was a closure of the ocean and the formation valsya a single continent. Apparently, these structures were a part of the ancient super-continent called Motherland.

Proterozoic mega level of cover, limited dates 1800-600 million years and is composed mainly metamorphosed quartz sandstone, sandstone and carbonate sediments. There you are, and volcanic intrusions of granitoids. Widespread, they were within the Northern and Middle Tenir Too, where the term tectonic blocks and kernel Kie rises. In general, they are to transform the conditions in the inland in a quiet tectonic regime. However, the nature of volcanic activity and rainfall indicates that the levels of 1300, 1100, 720 million years on the background of internal riplitnoy conditions the processes of continental rifting, the crust used Experiencing the tangential stretching, and at 830 million years, there were conditions vnutrikonti nentalnogo tangential compression, which expressed in the formation of intense folding, the introduction of granitic magmatism and regional metamorphism manifestation Institute.

Upper Proterozoic-Paleozoic mega level covers over 600 million years and the entire Paleozoic. It is composed of a variety of geological formations and distributed in all zones of tectonic Tenir Too and Northern Pamirs. The ages of strata in many cases are defined organic remains, and the masses of the FIR magmatiches – radiogeohronologicheskim datirova Niemi. A distinctive feature of the mega: the presence in its structure formations of several ocean basins and continental masses. In the initial stage of fragmentation occurred unity tion of the continent, the disclosure of oceanic Bass Basin, and in the end – the closure of the ocean, and again the formation of a unified continent as a result of accretion of previously separated blocks. At closing time, no ocean basins isolated Xia bottom tectonic complexes: nizhnepaleozoy sky (Caledonian) and Upper Paleozoic (Ger Qing).

Tectonic Complex early-Paleozoic accretion covers the formation of the Vendian System of terozoya and the entire Lower Paleozoic. In general, it is developed within the Northern, Middle, some of its fragments are found within the Southern Tenir Too and Tarim massif. In the North-Too Tenir these entities play a major role. At the bottom, they are back-arc ophiolites of the seas, partly oceanic environments, sandstone and igneous formations of island arcs. Here we encounter are clastic and carbonate sediments, characteristic of the continental shelf, slope and the foot. In the upper part of the complex is dominated by terrigenous deposits of coarse fragmental and large granite massifs. Within the Middle Tenir Too coarse clastic marked at the bottom of terrigenous and volcanic strata characteristic of rift environments, above – clayey and siliceous shales and car bonatnye continental passive margin deposits nent. Up, they are replaced by terrigenous deposits of intermontane basins. In South Tenir Too complex occurs as GOVERNMENTAL separate units composed of carbonate, sandstone and volcanic rocks of the rift genetic conditions. Starting from the lower Ordovician vetch, are developed ophiolite complex with ty pichnymi signs midocean ridges. Within the Tarim massif geology cal body level considered similarly formations of the Middle Tenir Too, however, the upper part, rather than developed it psephytic thickness, is presented here carbo nate sediments.

Reconstruction paleogeodynamic this complex situation of education showed the following. In the late Proterozoic continent of ancient homeland tions experienced crushing, resulting rift formed structure. During the late Vendian – Early op dovika between the North and Mid Tenir Too emerged oceanic basin, named Saki. Its width, according to some estimates, reached more than 1.5-2.0 thousand kilometers. Simultaneously but with him there were relatively small continental blocks. Early in the second half – in the early Middle Ordovician to the ocean begins to decline, in the Northern Tenir Too island formed with the formation of back-arc basins. Such an envi Substitution retained until the second half of the Late Ordovician, when the ocean is closed and is absorbed by the subduction of polnos Tew. In its place remained suture – a seam, to-ing after the imposed motions into a tectonic structure, called a major structural line Tenir Too. An accretion of continental blocks GOVERNMENTAL and island arcs, in the late Ordovician on the site of the Northern and Middle Tenir Too emerged mountainous area, where the basins were deposited coarse fragmental sediments, and raised ment penetrated the large masses of granitoids. Within the South Tenir Too complex set plexes two ocean basins, the time-rye is being developed in the early Ordovician (possibly even an early hour above), and land masses.

Tectonic complex Late Palaeozoic accretion is the most widespread of Education in Kyrgyzstan. North and Sredin HYDRATED Tenir-Too in the middle and late Paleozoic microcontinent merged into one, to-ing the title of Kirghiz-Kazakh. In North Tenir Too Silurian is represented by intrusions of granitoids, sedimentary rocks of the Devonian begin with. The entire Devonian – Lower Permian is represented by Terry Ray, volcanic and intrusive on the formation of variegated composition. In the Mid-Too Tenir most of the Silurian are also absent, and only go Chatkal Ridge terrigenous and volcanic strata of the island arcs. There are Lower-Middle Ground nye volcanics. Those at the top of the Middle Devonian – Lower Carboniferous within the Mid-Too Tenir presented below ground sandstone, and above – marine carbonate and kremnis tymi deposits. Middle Carboniferous – Permian lower tions is represented by terrigenous, volcanic and intrusive formations gene motley composition.

Within the South Tenir Too at Lura B-Lower Carboniferous widespread ofio litas, which are complex and Turk stanskogo Yagnob oceanic basins and island terrigenous and volcanic rocks. Play an important role clastic and carbonate sediments of continental blocks, as well as the slopes and foothills of the continental margins.

Reconstruction paleogeodynamic conditions showed that at this level in the north (hereafter in modern coordinates, in ancient times they were tion by others) Kirghiz-Kazakh settled the continent to the south – Travel kestansky ocean, etc. – Tarim continent and ocean Yagnob. In the Silurian – rannedevonskoe time for sowing. and the south. the outskirts of Kirghiz-Ka zahskogo continent established an active continental-margin conditions (such as the conditions of modern America to the west of the Andes), due to striction due to subduction processes, both from the north of the oceanic lithosphere Balkhash oceanic analysis (outside of Kyrgyzstan), the pressed-rye continued without interruption until the early Permian, and from the south – the lithosphere of the Turkestan Ocean. The latter was located in the space between the South and Wed dinnym Tenir Too. The width of paleomagnetic data in the Devonian time is attained at least 2200 km. Inside of Turkestan oceanic basin stands Ulan-Alai continental block. In the Silurian – rannedevonskoe time subdutsirovala oceanic lithosphere as a na north (in modern coordinates to) the Kirghiz-Kazakh continuum component, and in the south – at Ulan-Alai micro rokontinent. Starting with a Givetian age environments of the Devonian, the subduction process and weaken, until the late Early Carboniferous including significantly, the continents bordering the crust Paet, the situation with the passive margin sediments of the same type of precipitation Niemi: bottom – terrigenous ennyh, above – carbonate. In Ulan-Alai microcontinent of carbonates, volcanics occur mainly secondary, less acidic and basic compounds with alkaline slant. Beginning with the Early Carboniferous Serpukhovian age subduction of oceanic lithosphere processes Turkestan renewed, but only to the north, under the Kirghiz-Kazakh continent concentration. Tarim continent on the territory of Kyrgyzstan represented a very narrow band of carbonate of Noah, named Kulgedzhelinskim ba rum. At the west. its continuation in the territory of Tajikistan, called out Rabutsky block, to-ing bears the Paleozoic sections, gathering nye with cuts Tarim massif. For facial features of these cuts, the unit was quite large. Kulgedzhelinskaya band was part of a vast con continent, uniting Tarim massif to the east and Eastern European (Russian) card form on the west. Geological bodies associated with Yagnob nye ocean, mainly in the outputs dyat Tazhikistana. Judging by the sharp voduzhnym complex, which in the axial part of the Turkestan-Alai, it tests the lithosphere subduction beneath the shaft Tarim continent.

Within the Northern Pamir known ofio Litas back-arc basins and volcanic arcs sharply vnyh Lower Carboniferous. They are the testimony of UT on the rule of the ocean environment to the south, to the lithosphere-cerned subdutsirovala to se ver (under the continent, situated south of Ocean Yagnob). Apparently, they are connected by the ocean and Paleotetis were brought here by subsequent movements.

Middle Carboniferous – Lower Permian terrigenous county representation, often coarsely fragmented sea, and at the top and land on the proposition. There are large intrusive igneous mass and volcanics. At this time occurred in all regions of the closure of ocean basins České. However, on the northern. and the south. Okra is not Kirghiz-Kazakh continent gentlemen update themselves the situation of the active edge of the continuum component, ie from the south resumed subduction processes. In the axial part of the Turkestan-Alai mountain ranges also come Lower Permian magmatiches Kia complexes active margins of the continent, showing the magnetosphere is immersed subduction to the north of the Yagnob Ocean. Accretion of the late Paleozoic continental united all the masses, and in any gyzstana Kyr mountain structures. As a consequence of intense tangential compression of the crust is not only closed the oceans to the width of Noah a few thousand kilometers and tests whether the strong reduction of the width, or even disappeared with all the major continental blocks. For example, once a vast Tarim continent concentration in Kyrgyzstan turned into a narrow strip of a width of 10-15 km. Sredin HYDRATED Tenir Too wide to-cerned at the Tashkent meridian reaches more than 350 miles, much su zhayas to the east, near the river valley. Sary-Jaz has a width of 7 km and beyond, in China, all wedges. Fergana unit experienced counter-clockwise rotation, resulting in the east of it were formed sigmoid (horizontal folds) and the Talas-Fergana diagonal shear displacement amplitude to-cerned reaches 180-250 km.

Upper Permian – Lower Triassic formed in Kyrgyzstan, the individual you are isolated passages thick clastic and volcanic sedimentation Cove and contrasting acidic, alkaline and carbonatite intrusive igneous E arrays. Despite its small size, these structures are important in geo ogy and economy of Kyrgyzstan. They evidence the proof of the general uplift of the region and the domination of the scattered riftingovoy situation. With this level are associated numerous and various large-scale mineral deposits.

Mesozoic-Cenozoic mega widely distributed in the territory of Kyrgyzstan. By the nature of the tectonic regime during the accumulation in the thick of its structure are two of the complex. The lower, Mesozoic-nizhnekayno zoysky complex formed in the platform environment, Noah, and the upper – verhnekaynozoys cue complex – in orogenic.

Mesozoic-Early Cenozoic platform complex in Kyrgyzstan unevenly distributed evenly. Middle-Upper Triassic in large parts of Kyrgyzstan is missing. These include the red-colored volcanic and clastic strata ac tively marginal-continental climate in the northern Pamir and small diatremes (types of igneous rocks formed by the explosion wa) on the Turkestan-Alai. Jurassic System in Kyrgyzstan is widespread and is represented by terrestrial clay and sand formation education, containing at the bottom of large deposits of nye black and brown coal, to lay the on-rye in the plains in the humid climate. However, in the upper part of terr Eagen rocks, gypsum deposits occur, which indicates the beginning of the arid climate. Mel – the average Paleogene platform deposits represented in the marine facies is found only in parts of the Ferghana Tenir Too and Northern Pamirs. They are composed of clay and carbonate sediments. To the east of the presence of Fergana range of chalk is not known. It is assumed that it exists in the lower red beds, Paleogene indexed. They pre sented by ground gypsum-bearing clastic sediments bubbled desert. In many places there are Kyr gyzstana Cretaceous-Paleogene basalts of age.

Verhnekaynozoysky orogenic complex is fully represented, mostly coarsely fragmented sediment gotsena oli-Holocene, educated in the mountains of the permutation and occurs in all basins of Kyrgyzstan. The lower ranks of these formations is a red-colored, gray tones predominate upward. In the lower part of the red, there lie a variety of rock salt and gypsum, decrees colliding on a hot arid climate, but more frequent in the upper strata associated with glaciers.