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231.
The SW Antalya Complex is an assemblage of Mesozoic carbonate platform, margin and ophiolitic rocks which record the formation and tectonic emplacement of a small Mesozoic ocean basin. The late Cretaceous ophiolitic rocks are located at two localities, namely the relatively intact Tekirova ophiolite to the east of Kemer zone and the dismembered Gödene ophiolite to the west of Kemer zone. The Tekirova (Antalya) ophiolite comprises harzburgitic tectonites, ultramafic to mafic cumulates, isotropic gabbros and sheeted dikes. Numerous isolated dikes, ranging in thickness from 5 cm to 10 m, intruded the crustal rocks at different structural levels. The isotropic gabbros are represented by gabbro, diorite and quartz diorite rocks with granular to ophitic–subophitic textures. The isolated dikes are characterized by dolerite, diabase and microdiorite with ophitic, intersertal and microgranular textures. These rocks exhibit tholeiitic to alkaline compositions. New geochemical data presented in this paper from the isolated dikes and isotropic gabbros suggest that there are three main types of parental basic magmas that form the oceanic crustal rocks of the Tekirova (Antalya) ophiolite. These are (1) IAT series which can be referred to the Group I isolated dikes and isotropic gabbros; (2) low-Ti boninitic series characterized by the Group II isolated dike and isotropic gabbros; and (3) OIB-type including the Group III isotropic gabbros. The geochemical evidence suggests that the crustal rocks of the Tekirova (Antalya) ophiolite were generated from a progressive source depletion from island arc tholeiites (IAT) to boninites. Therefore, a fore-arc tectonic setting seems likely for the generation of the crustal rocks from the Tekirova (Antalya) ophiolite in the southern branch of Neotethys during the Late Cretaceous. The OIB-type alkaline isotropic gabbros are thought to have resulted from either (1) a late-stage magmatic activity fed by melts that originated within an asthenospheric window due to slab break-off or (2) subduction of a ridge system which generated OIB source across the asthenospheric window that has been no influence of fluids from the subducted slab into the overlying mantle wedge, shortly before the emplacement of the Tekirova (Antalya) ophiolite onto the Tauride platform. 相似文献
232.
233.
老挝万象平原不同矿区盐丘构造发育程度不同。由于盐丘控制了钾盐矿层的分布,因此研究盐丘及其发育程度并对其分级,对万象平原及其周边地区的钾盐找矿具有重要参考意义。通过对万象平原大量的钾盐勘查资料研究,将该区域内盐丘构造按发育程度不同分为Ⅲ级(较发育)、Ⅱ级(发育)和Ⅰ级(极发育)三个级别。属Ⅲ级的有通芒盐丘和班海盐丘,属Ⅱ级的有农刀及塔贡盐丘,属Ⅰ级的为农哈湖盐丘。在万象平原进行钾盐勘查时,发育程度不同的盐丘及盐丘的不同部位的工程布设不同,找矿效果也不同。 相似文献
234.
A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry
of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company.
One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth
of 1000–1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential
threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence
due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and
the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference
of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several
scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land
subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer
drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing
a rebound of 0.6–0.7 cm.
Electronic Publication 相似文献
235.
In the present study, the removal of Cu(II) was evaluated by raw and calcined phosphogypsum (PG) as an industrial product. The role of experimental factors on the removal of Cu(II) was examined by using D‐optimal and Taguchi designs. The experimental factors and their related levels were selected as initial pH of 3–6–8, adsorbent content of 5, 10, and 25 g L?1, contact time of 5, 10, and 20 min, and temperature of 20, 40, and 60°C. The results are evaluated by ANOVA test to extract important experimental factors and their levels. The performances of the suggested factorial designs were then compared and regression models that took into account the significant main and interaction effects were suggested. Taguchi design was found as a reliable solution with less number of experiments for adsorption studies with the optimized values. The resultant removal efficiency is calculated as 78.34%. The results revealed that calcined PG is an appropriate adsorbent for Cu(II) removal from leachate of industrial waste. 相似文献
236.
This paper presents a 2.5D scattering of incident plane SV waves by a canyon in a layered half-space by using the indirect boundary element method (IBEM). A free field response analysis is performed to provide the displacements and stresses on the boundary of the canyon where fictitious uniform moving loads are applied to calculate the Green’s functions for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The free field displacements are added to the fic... 相似文献
237.
238.
Landfill site selection by using geographic information systems 总被引:3,自引:3,他引:3
One of the serious and growing potential problems in most large urban areas is the shortage of land for waste disposal. Although
there are some efforts to reduce and recover the waste, disposal in landfills is still the most common method for waste destination.
An inappropriate landfill site may have negative environmental, economic and ecological impacts. Therefore, it should be selected
carefully by considering both regulations and constraints on other sources. In this study, candidate sites for an appropriate
landfill area in the vicinity of Ankara are determined by using the integration of geographic information systems and multicriteria
decision analysis (MCDA). For this purpose, 16 input map layers including topography, settlements (urban centers and villages),
roads (Highway E90 and village roads), railways, airport, wetlands, infrastructures (pipelines and power lines), slope, geology,
land use, floodplains, aquifers and surface water are prepared and two different MCDA methods (simple additive weighting and
analytic hierarchy process) are implemented to a geographical information system. Comparison of the maps produced by these
two different methods shows that both methods yield conformable results. Field checks also confirm that the candidate sites
agree well with the selected criteria. 相似文献
239.
The geography of tourism and recreation in Bulgaria 总被引:1,自引:0,他引:1
Marin Bačvarov 《GeoJournal》1984,9(1):71-73
240.
Milica?G.?Radakovi? Ivana?To?i?Email author Nikola?Ba?evi? Dragan?Mladjan Milivoj?B.?Gavrilov Slobodan?B.?Markovi? 《Theoretical and Applied Climatology》2018,133(3-4):887-898
In this study, we apply De Martonne and Pinna combinative indices to analyze the aridity in Central Serbia. Our dataset consists of mean monthly surface air temperature (MMT) and mean monthly precipitation (MMP) for 26 meteorological stations during the period 1949–2015. MMT and MMP are used for calculating monthly, seasonal, and annual aridity indices for period of 66 years. According to the De Martonne climate classification, we determine five, three, and four types of climate on the monthly, seasonal, and annual basis, respectively. During the observed period, winter was extremely humid, spring and autumn were humid, and summer was semi-humid. Humid and semi-humid climate with Mediterranean vegetation are identified by the annual Pinna combinative index. We find that there is no change in aridity trend in Central Serbia for the period 1949–2015. Aridity indices are additionally compared with the North Atlantic Oscillation and El-Niño South Oscillation in order to establish a possible connection with the large-scale processes. Results are further compared with several earlier studies of aridity in Serbia. With this study, the analysis of aridity in whole Serbia has become complete. 相似文献