The Role of Fault Seal of Middle Miocene (Chokrak formation) Fields at Northern Edge of West Kuban Trough in

2010 ◽  
Author(s):  
A. Derduga
Keyword(s):  
Middle Miocene ◽  
Northern Edge ◽  
West Kuban Trough

scholarly journals Levels of changes in the genus Pinus Linné in the composition of Mesozoic and Cenozoic flora and vegetation as an additional criterion for the division of sediments by the Mesozoic and Cenozoic of Ukraine

2021 ◽  
Vol 30 (4) ◽  
pp. 741-753
Author(s):  
Olena A. Sirenko ◽  
Olena A. Shevchuk
Keyword(s):  
Species Diversity ◽  
Early Cretaceous ◽  
Late Jurassic ◽  
Middle Miocene ◽  
Geological Time ◽  
Tectonic Structures ◽  
Historical Aspect ◽  
Quantitative Changes ◽  
Cenozoic Sediments

The article presents an analysis of a large array of results of palynological studies of Mesozoic and Cenozoic sediments of Ukraine and adjacent regions of Belarus and Russia. Numerous literature data on the palynological characteristics of Meso-Cenozoic sediments and the materials of the authors are summarized according to the results of spore-pollen analysis of Mesozoic and Cenozoic sediments within the main tectonic structures of Ukraine. It has been established that the genus Pinus (Pinaceae) is an integral part of the Meso-Cenozoic flora of Ukraine. Although, the participation in the flora and vegetation of the genus Pinus and its species diversity in different periods of geological time were different. Despite the long history and significant achievements of palynological research of Meso-Cenozoic sediments of Ukraine, no attention has been paid to the historical aspect of Pinus development in the Meso-Cenozoic flora. This work is presented as the first stem to fill this gap. The genus Pinus has a large stratigraphic range, but its species diversity and quantitative changes in the composition of Mesozoic and Cenozoic flora of different ages are markedly different. The analysis of these changes made it possible to trace the emergence and main levels at which the species composition was renewed and the role of Pinus in flora increased during the Mesozoic and Cenozoic. According to the results of the research, 5 levels of increasing the participation of the genus Pinus and changes in its species affiliation in the Mesozoic flora were established: Aalenian period of the Middle Jurassic (appearance of the first representatives of Pinus); Oxfordian time of the Late Jurassic; Valanginian – Early Barremian times of the Early Cretaceous; Albian time of the Early Cretaceous; Late Campanian time of the Late Cretaceous. 5 levels of increasing the role of Pinus and its species diversity for the flora and vegetation of the Cenozoic were also established: Oligocene time of the Paleogene, Konkian-early Sarmatian time of the Middle Miocene; early Pontian (Ivankov) time of the Late Miocene; early Kimmerian time (early Sevastopol) of the Early Pliocene and Martonosha time of the Early Neopleistocene. Certain levels have been traced for the similar age of Cenozoic flora of Belarus and Russia.

Geodynamic evolution of the Pan-African belt in central Africa with special reference to Cameroon

2004 ◽  
Vol 41 (1) ◽  
pp. 73-85 ◽  
Author(s):  
Sadrack Félix Toteu ◽  
Joseph Penaye ◽  
Yvette Poudjom Djomani
Keyword(s):  
Central Africa ◽  
West African ◽  
Fault System ◽  
North Central ◽  
West African Craton ◽  
The North ◽  
Pan African ◽  
Northern Edge ◽  
The Many

The Pan-African belt in central Africa has benefited from the many petrographic, structural, and geochronological studies in the recent years that have improved our understanding of the belt. However, those studies have also produced various and often divergent evolutionary models for the belt, some of which do not even involve well-defined cratons. Following a review of the available data in Cameroon, we propose a model of continent–continent collision that involved the Congo craton and the north-central Cameroon active margin showing Archean to Paleoproterozoic inheritances. This model is based, among others, on (i) the prominent role of the Congo craton as demonstrated by the regional extension of external nappes on its northern edge and the concomitant exhumation of the 620 Ma granulitic rocks believed to have formed at the root of the collision zone, and (ii) the late development of a strike slip fault system in central Cameroon as the result of horizontal movement following the multistage collision. In the general framework of the Pan-Africano – Brasiliano belt, a comparison of the kinematic and age of deformation north of the Congo craton to that east of the West African craton, suggests that the overall tectonic evolution of the mobile domain between both cratons is controlled by their relative motion.

The role of the flexural rotation/rolling hinge model in the tectonic evolution of the Alaşehir graben, western Turkey

2002 ◽  
Vol 139 (1) ◽  
pp. 15-26 ◽  
Author(s):  
GÜROL SEYİTOĞLU ◽  
OKAN TEKELİ ◽  
İBRAHİM ÇEMEN ◽  
ŞEVKET ŞEN ◽  
VEYSEL IŞIK
Keyword(s):  
Tectonic Evolution ◽  
Middle Miocene ◽  
Hanging Wall ◽  
Fault System ◽  
Sequential Process ◽  
Western Turkey ◽  
Extensional Structure ◽  
Hinge Model ◽  
Sedimentary Unit

The Alaşehir graben is a well-defined prominent extensional structure in western Turkey, generally trending E–W and containing four sedimentary units. At the beginning of graben formation during Early–Middle Miocene times, the first fault system was active and responsible for the accumulation of the first and second sedimentary units. In Pliocene times, a second fault system developed in the hanging wall of the first system and a third sedimentary unit was deposited. The recently active third fault system separates older graben fill and a fourth sedimentary unit. Activity on each fault system caused the rotation and uplift of previous systems, similar to the ‘flexural rotation/rolling hinge’ model, but our field observations indicate that the rotated first fault system is also active, allowing exhumation of larger amounts of rock units. This paper documents that graben formation in western Turkey is a sequential process. Its different periods are represented by three fault systems and associated sedimentation. Consequently, recent claims using age data from only the second and/or third sedimentary units to determine the timing of graben formation are misleading.

Role of predation and hunting on eastern cottontail mortality at Cape Cod National Seashore, Massachusetts

2008 ◽  
Vol 86 (8) ◽  
pp. 918-927 ◽  
Author(s):  
Kelly M. Boland ◽  
John A. Litvaitis
Keyword(s):  
Weather Conditions ◽  
Cape Cod ◽  
Sylvilagus Floridanus ◽  
Limited Information ◽  
Mortality Factors ◽  
Northern Edge ◽  
Eastern Cottontail ◽  
Partial Compensation ◽  
National Seashore

The degree that hunting may influence game populations depends on whether hunting mortality is additional to (additive) or replaces (compensatory) natural-caused mortalities. In response to limited information on the effects of exploitation on eastern cottontail ( Sylvilagus floridanus (J.A. Allen, 1890)) populations within Cape Cod National Seashore (CCNS), we initiated an investigation of cause-specific mortality using transmitter-equipped cottontails in hunted and nonhunted areas as a way to examine the additive versus compensatory aspect of hunting. Predation caused >70% of all deaths, whereas hunting caused 10% of deaths in the areas sampled. Survival rate was substantially lower among hunted sites (0.05) than at nonhunted sites (0.19) during the winter–spring of year 1, but there was no difference between hunted (0.33) and nonhunted (0.40) sites during year 2. Lower survival in year 1 was likely due to deep and persistent snow that increased vulnerability to predation and probably reduced the prospect for hunting mortalities to be compensated by reductions among other mortality factors. However, at least partial compensation apparently occurred during year 2 when winter weather was less severe. Cottontails at CCNS are near the northern edge of their geographic range and therefore may be ultimately limited by severe weather conditions. Compared with predation, we do not believe that the current levels and distributions of hunting influence cottontail populations at CCNS.

scholarly journals Vertical thermobaric zoning of hydrocarbon deposits of the Eastern oil- and gas-bearing region of Ukraine

2019 ◽  
Vol 3 (180) ◽  
pp. 60-75
Author(s):  
Oleksandr Prykhodko ◽  
Ihor Hrytsyk ◽  
Ihor Kurovets ◽  
Svitlana Melnychuk
Keyword(s):  
Oil And Gas ◽  
Vertical Section ◽  
Sedimentary Basins ◽  
Geological Structure ◽  
The North ◽  
Northern Edge ◽  
Different Depths ◽  
Hydrocarbon Deposits ◽  
Gas Bearing

For the predictive appraisal of the perspective exploratory territories as well as prediction of separate producing horizons of prospecting and exploration areas for oil and gas it is necessary to establish the regularities of distribution of already explored deposits of hydrocarbons with structural-tectonic construction, lithological-stratigraphic features, hydrogeological and geothermobaric conditions of oil- and gas-bearing region taken into account. Interconnection between geothermobaric parameters and the phase state of hydrocarbons in the vertical section should be an important factor for the solution of the posed task. Within the limits of the Eastern oil- and gas-bearing area of Ukraine, the spatial zoning is established in the location of gas, oil and gas-condensate deposits. As a whole, the distribution of temperatures and pressures at different depths, average geothermal gradients, gradients of the lithological-stratigraphical horizons of the same name (sustained both as to the area and thickness) are closely connected with the deep geological structure of the studied region (area) and confirm the existing notions of the role of tectonic, lithological-stratigraphic and hydrogeological factors in the formation of the thermal regime of sedimentary basins. Vertical zoning of the distribution of hydrocarbon deposits of oil- and gas-bearing horizons was developed according to geothermobaric parameters of the north-western part of the Dnieper-Donets Depression and 8 areas from 15 ones of the Eastern oil- and gas-bearing region, namely: Monastyryshche-Sofiivka and Talalaivka-Rybalske oil- and gas-bearing areas, Glynsk-Solokha gas- and oil-bearing area, Ryabukhyne-Northern Golubivka and Mashivka-Shebelynka gas-bearing areas, Rudenky-Proletarske oil- and gas-bearing region, Krasna Rika gas-bearing area and also oil- and gas-bearing area of the Northern edge. Revealed regularities of the distribution of formation temperatures, pressures, geothermal and thermobaric coefficients with peculiarities of the tectonic structure of the Dnieper-Donets graben taken into account will make it possible to solve theoretical problems connected with hydrocarbon migration, the formation and preservation of deposits in more well-founded way that will make it possible to conduct prospecting for new fields at great depths within the studied territory more effectively.

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