lesser caucasus
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2022 ◽  
Vol 8 (1) ◽  
pp. 71-75
Author(s):  
R. Orujeva

Gay gray-brown soils are distributed mainly in the foothills of the Lesser Caucasus, on the Ganja-Gazakh plain and in the lower reaches of the Araz basin. They are formed by changing volcanic rocks in hot and dry climates. In the process of erosion and soil formation, pyrite, alunitized and other sulfur-containing rocks turn into gazh, on which gray-brown gazh soils are formed. As a result of human activity, i. e. deep plowing and irrigation, these lands are being converted. It turned out that the transformation of these soils is clearly felt in the thickness of the humus layer, its distribution along the profile, quantity and composition. The thickness of the humus layer increases from 40–45 cm to 100 cm. As a result of the transformation, the length of the humus profile is constantly decreasing. Changes in the composition of humus led to an increase in the content of humic acids. Although the coefficient in the uncultivated area decreased from 1.36 to 0.80, in the irrigated area it changed from 1.70 to 0.93.


2022 ◽  
Vol 162 ◽  
pp. 103117
Author(s):  
Hugues-Alexandre Blain ◽  
Ana Fagoaga ◽  
Christian Sánchez-Bandera ◽  
Francisco J. Ruiz-Sánchez ◽  
Roberto Sindaco ◽  
...  

2021 ◽  
Vol 30 (4) ◽  
pp. 692-705
Author(s):  
Musa Nasib ogly Mammadov ◽  
Gultekin Javad gizi Babayeva

Drawing from the determined differences between iron-titanium oxide minerals, we analyzed the conditions of crystallization and evolution of late-Cretaceous magmatic complexes of the Lesser Caucasus. It was found that the rocks of basalt-andesibasalt complex, which correspond to the early substage (upper Coniacian-lower Santonian) of late-Cretaceous volcanism in the Qazakh, Agjakand, Agdara depressions, have crystallized in the conditions of relatively highly- thermobaric crystallization of titanomagnetite, poorly differentiated and evolutionized according to the Fenner trend. In the second substage of volcanism, due to decrease in permeability of the Earth’s crust, the elevation of the remaining magma to the upper horizons was hindered. Therefore, within the Qazakh depression, shallow intermediate sites of crystallization developed where moderately titaniferous magnetite crystallized with the participation of oxidized fluids earlier than hornblende, pyroxene and plagioclase. Thus, the remaining magma evolutionized its composition through Bowen’s reaction series. In the Agjakand and Agdara depressions, change of previous expansion to compaction was the cause of hindering of partly fractioned portion of the magma. The latter thermally interacted with the above-embedded maghemite, hematite and in a number of cases magnetite. In the Khojavand depression, rocks of trachibasalt- trachiodolerite complex, which characterize the late substage of the Santonian volcanism, contain moderately titanium magnetites and maghemites. In the second substage of volcano-plutonism, rocks of tephrite-teshenite complex developed. There, accompanied by oxidized fluids, highly-clayey titanomagnetite crystallized before chrome-diopside and salite. However, the ulvospinel titanomagnetite in teshenites, having associated with barkevikite and kaersutite, crystallized at a relatively higher temperature. Within the Senonian volcanites of the Azykh depression, along with the moderately-titanium magnetite, chromic titanomagnetite and rarely chromite was determined. Similar mineralogical diversities are also characteristic for the Gochas depression.


2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Banu Kaya özdemirel

Cross taxa congruence was investigated between butterfly taxa and ecological community for fine spatial scale (10 × 10 km² UTM grids) in north-eastern part of Turkey. The study area was evaluated within the scope of systematic conservation planning, and analyses were performed for sets of priority protected areas composed using complementarity-based site selection software Marxan. Cross taxa congruence was subsequently examined both in species richness and ecologic complementarity. Accordingly, it has been observed that the cross-taxon congruence between butterfly taxa and ecological community was relatively better than the results of previous studies. Another remarkable finding is that ecological community was a more robust surrogate than butterfly taxa. Although the results are valuable for conservation studies, they highlight the fact that a simple surrogate-based site selection would be inadequate to represent overall biodiversity.  The weakness of congruence patterns among surrogates would also lead to gaps in biodiversity conservation. These findings therefore draw attention to the necessities of incorporating surrogates of distinct ecology or some other surrogates like environmental parameters into conservation planning. Otherwise, there may be mistakes regarding species representation and the vast majority of species may be misrepresented in protected areas and protected area plans. At this point, it should be emphasized that understating cross taxa congruence and/or relationships is a key component for efficient biodiversity conservation.


2021 ◽  
Vol 2 (6) ◽  
pp. 36-42
Author(s):  
B. Tutberidze ◽  
M. Akhalkatsishvili

These Erusheti Plateau is an integral part of the volcanic highland of Southern Georgia. It is located northern part of the Lesser Caucasus in the convergence zone of the Afro-Arabian and Eurasian lithosphere tectonic plates. The territory is almost totally covered with strong volcanic and volcano-sedimentary formations of Goderdzi suite with different lithologies and facies. The suite is formed in the Late Miocene - Early Pliocene Age, about from 11.8±4 to 13.6±3.1 Ma. Erusheti Plateau overall, are not characterized by many centers of eruption; Here we discuss eruption histories of the large polygenic volcanic massive Dokhuz-Puar and a monogenic volcano Datvistskaro are clearly seen among the volcanogenic structures of Erusheti Plateau. The eruption products of Dokhkuz-Puar volcano are dacitic-containing tuff-breccias and lava flows. The activity of Datvistskaro volcano was expressed only by the eruption of pyroclastic deposits containing andesite basalts. The main constituent minerals are: plagi­oclase and hornblende mega-crystals in dacites; augite-olivine and base plagioclase – in andesite basalts. With their geochemical properties, all the rocks of the rocks of a calc-alkali series. Dacites and andesite-basalts do not feed from a common magmatic source and consequently, are not the product of differentiation of the same magma. The work is the first to describe the natural amazing natural geoforms developed in pyroclastolites of Datvistskaro volcano: gigantic stone columns, mushroom-shaped stone caps and stone lances.Should be noted that no detailed mine­ralogical-petrological study of the rocks common in the study area has done to date. The main purpose of the given work is filling this gap.


Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1069
Author(s):  
Olavi Kurina ◽  
Heli Kirik

A new species—Docosia caucasica sp. n.—has been described from material collected from the Lesser Caucasus Mountains in Georgia (Sakartvelo). The new species belongs to a group of Palaearctic species characterized by distinct posterolateral processes of gonocoxites and apically modified setae at the posteroventral margin of the gonocoxites medially. Within the group, D. caucasica sp. n. is most similar to D. landrocki Laštovka and Ševčík, 2006 in having a similar outline of the medial process of posteroventral margin of the gonocoxites and the gonostylus. There is also a marked difference within the partial cytochrome c oxidase subunit 1 gene (COI) sequence of D. caucasica sp. n. and other Docosia spp. available in public databases. As the new species is described from a single male specimen only, the adequacy and code compliance of that are discussed.


Author(s):  
Konstantine (Kote) Pitskhelauri ◽  

Georgia is situated in Caucasia, between the Black Sea and the Caspian Sea. Its terrain is created by the Greater and the Lesser Caucasus, rivers with great volume of water flowing between them and coastal plains. The territory of the whole Caucasus and, specifically, Georgia, is one of the main communication areas linking ancient Steppe empires with Near Eastern civilizations (pl. 1), which, alongside rich natural conditions, significantly determined formation of human society from ancient times and proved favourable to its development. Formation and evolution of the human society in any corner of the earth, from the earliest times to ancient civilizations, largely depends on the geographic environment and reasonable exploitation of natural resources by humans. With its mild climate, fertile lands, flora, fauna, alpine pastures and low-lying fields, diverse natural resources, extensive river network, etc. Georgia has always provided convenient conditions for human habitation and development of economic activities. Southern slopes of the Caucasus Mountain Range and the highlands of the Lesser Caucasus are especially rich in metallogenic provinces. The present article deals with when production of different metals started here and whether it became one of the main bases for development of the society.


2021 ◽  
Vol 3 (4) ◽  
Author(s):  
S. Kekelia ◽  
Nona Gagnidze ◽  
I. Mshvenieradze ◽  
G. Kharazishvili

The paper presents brief characteristics of geological environments of ore deposit occurrences in Turkey, Georgia and Armenia. They can be attributed to Kuroko-type deposits, being distinguished by the character of ore accumulation. To the west, in Turkey, there are epigenetic and hydrothermal-sedimentary copper-zinc deposits that were formed in deep restricted basinal settings. An example of the latter is the Chayeli deposit.To the east, in the Caucasus, we have predominantly only epigenetic deposits. Besides, in the Bolnisi mining district (Georgia) there is the Madneuli deposit which represents an example of polyformational deposit. Here, within the restricted territory, have been concentrated:barite, barite-polymetallic, gold-bearing secondary quartzite, large-scale stockworks of copper ores. Judged by the 87Sr/86Sr ratios, some volcanites which are spatially associated with ores, might have been products of the “differentiation” of undepleted mantle, or other magmas that were generated in the lower part of the earth crust.In the Alaverdi ore district in Armenia, there are Jurassic volcanodepressions that host copper, copper-zinc and barite-sulfide ores. All the deposits of the Alaverdi district, porphyry copper including, contain economic reserves of ores.On the basis of available literature material and our own data, there has been created a mental-logical geological-genetic model of volcanogenic deposits.


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