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1.
Ş. Üşümezsoy 《Mineralium Deposita》1990,25(2):89-95
Kefdag and Soridag chromite pods occur in upper mantle residual peridotites, which consist of harzburgite and dunites. The peridotites represent the residual of multistage, depleted upper-mantle peridotites. The chromitite bodies were formed during the uprising of chromium-rich picritic melts, through the residual upper mantle diapir, along the magma conduits. Chromitite grains were deposited in the caves of the magma conduits under the control of the convection currents. 相似文献
2.
阿尔金山羌塘高原水资源开发及罗布泊钾盐矿建设的设想 总被引：1，自引：1，他引：0
《阿尔金山及羌塘高原水资源开发利用与保护考察报告》编写组 《干旱区地理》2007,30(6):785-790
阿尔金山水资源相对丰富,是巴音郭楞蒙古自治州河川径流的主要形成区之一,巴音郭楞蒙古自治州若羌县罗布泊镇钾盐贮量很大,经济效益可观,但水资源成为了罗布泊钾盐矿发展的限制性因素。能否把阿尔金山的水资源作为罗布泊钾盐矿发展的支撑,是我们必须回答的一个问题。本文利用新疆维吾尔自治区水利厅阿尔金山野外考察资料,分析阿尔金山的水系与湖泊、自然地理和社会经济特点,以期为探讨阿尔金山能否作为罗布泊钾盐矿开发的水源条件提供理论依据。 相似文献
3.
Calcic skarns and transversal zoning in the Banat mountains, Romania: indicators of an Andean-type setting 总被引：1，自引：1，他引：0
Ş. N. Vlad 《Mineralium Deposita》1997,32(5):446-451
Calcic skarn deposits related to Upper Cretaceous – Paleocene banatitic intrusions are widely developed in the Banat Mountains
(southwestern Romanian Carpathians). There is a spatial distribution of banatitic igneous rocks and associated ore deposits
in parallel zones, due to subduction beneath the southwest Carpathians. As a result three distinct petro-metallogenetic units
developed, i.e. marginal unit: Moldova Nouă– Sasca; median unit: Ciclova – Oravita; and the inner unit: Dognecea – Ocna de
Fier. The magmatism changed inland from monzonite and diorite → granodiorite occurrences to granodiorite → granite plutons.
The related mineralization shifted simultaneously from Cu (Mo) to Cu-Mo (W) and eventually Fe(Cu)/Pb-Zn. The distribution
of both magmatism and related ore deposits in parallel petro-metallogenetic zones is considered similar to that in the Andes.
In particular, calcic skarns and related ore deposits that occur in these units show a transversal zonal variation represented
by compositional features of pyroxene and granat, sequence of mineralization and metallogenetic environment. Such zonal characteristics
represent an additional but nonetheless significant indicator for an Andean-type subduction-related setting.
Received: 3 June 1996 / Accepted: 10 January 1997 相似文献
4.
In the first part of this study, a series of stress-controlled hollow cylinder cyclic torsional triaxial shear tests were conducted on loose to medium dense saturated samples of clean Toyoura sand to investigate its liquefaction behavior. A uniform cyclic sinusoidal loading at a 0.1 Hz frequency was applied to air-pluviated samples where confining pressure and relative density was varied. Cyclic shear stress–strain changes, the number of cycles to reach liquefaction and pore pressure variations were recorded. Results indicate that the liquefaction resistances of uniform sands are significantly affected by the method of sample preparation and initial conditions. 相似文献
5.
Can Ş. Genç Şafak Altunkaynak Zekiye Karacık Metin Yazman Yücel Yılmaz 《Geodinamica Acta》2013,26(1-3):45-55
AbstractField studies on the Neogene successions in south of ?zmir reveal that subsequent Neogene continental basins were developed in the region. Initially a vast lake basin was formed during the early-Middle Miocene period. The lacustrine sediments underwent an approximately N-S shortening deformation to the end of Middle Miocene. A small portion of the basin fill was later trapped within the N-S-trending, fault-bounded graben basin, the Çubukluda? graben, opened during the Late Miocene. Oblique-slip normal faults with minor sinistral displacement are formed possibly under N–S extensional regime, and controlled the sediment deposition. Following this the region suffered a phase of denudation which produced a regionwide erosional surface suggesting that the extension interrupted to the end of Late Miocene–Early Pliocene period. After this event the E–W-trending major grabens and horsts of western Anatolia began to form. The graben bounding faults cut across the Upper Miocene–Pliocene lacustrine sediments and fragmented the erosional surface. The Çubukluda? graben began to work as a cross garden between the E–W grabens, since that period. © 2001 Éditions scientifiques et médicales Elsevier SAS 相似文献
6.
阿尔金山羌塘高原区域地表水可利用量及开发潜力分析 总被引：1，自引：1，他引：0
阿尔金山羌塘高原水资源开发利用与保护考察报告编写组 《干旱区地理》2008,31(3):422-427
确定水资源可利用量是实现阿尔金山及羌塘高原区域生态环境维护与经济社会发展双赢的保障.首先、提出用倒算法计算研究区的水资源可利用量,明确涉及变量的概念及算法.其次、计算了研究区各分区的地表水资源量,湖泊、湿地需水量,河道需水量等变量,最终确定了各分区的地表水资源可利用量.再次、结合各分区水资源利用现状,进一步分析了各分区的水资源利用潜力.结果表明:东羌塘山间盆地区地表水资源开发利用潜力较小;柴达木盆地西缘区开发利用潜力较大;阿尔金山北麓区开发利用潜力不大.最后、建议在研究区建立相应的水文、气象、生态等监测站点,为研究区水资源的合理开发、利用与保护奠定基础. 相似文献
7.
The granodiorite intrusion at Ocna de Fier-Dognecea in the western South Carpathians, Romania, triggered the formation of
a classic Fe-(Pb-Zn) skarn deposit. The intrusive is related to the larger composite Bocşa Laccolith five kilometres north
that is part of the regional Banatite Suite. Previous work indicated a K/Ar age of 65–57 Ma and postulated an Andean-type
subduction related tectonic setting for the intrusions. We report ion probe U/Pb zircon ages of 79.6 ± 2.5 Ma for the Bocşa
Laccolith and 75.5 ± 1.6 Ma for the Ocna de Fier Pluton, which date their emplacement. Fission track dating on titanite gives
slightly younger ages: 78 ± 4 Ma for Bocşa and 73 ± 4 Ma for Ocna de Fier. Together with zircon and apatite data from the
same samples, average cooling rates of 52 °C/Ma and 83 °C/Ma are calculated for the Bocşa and Ocna de Fier intrusives respectively.
A post-collision tectonic setting is proposed on the basis of field evidence, the timing of intrusions in the context of regional
tectonic evolution, and trace element geochemistry.
Received: 4 August 1998 / Accepted: 20 April 1999 相似文献
8.
In this study, it was performed a comparison of the performance and emissions of two methyl ester fuels: one obtained from animal fat and the other from crude canola oil, in a compression-ignition engine against diesel fuel. The experimental results compared with diesel fuel showed that significant reductions could be obtained by biodiesel derived from animal fat in carbon monoxide and oxides of nitrogen emissions. Carbon dioxide emissions showed a trend of decreasing with the biodiesel fuels. An increase in brake specific fuel consumption was observed for different biodiesel fuels when compared with diesel fuel. It was concluded that animal tallow methyl ester performed better than canola oil methyl ester, whereas slightly higher brake torque is observed with canola oil methyl ester. 相似文献
9.
《阿尔金山羌塘高原水资源开发利用与保护考察报告》编 《干旱区地理》2008,31(6)
阿尔金山及羌塘高原区域水资源相对丰富,巴音郭楞蒙古自治州若羌县罗布泊镇钾盐贮量很大,远景储量达2.45×108 t,潜在经济价值约5 000亿元,已成为我国新的钾盐开发基地,但周边区域水资源匮乏限制了罗布泊钾盐矿发展.开发钾盐需要大量的水资源,然而罗布泊地区极端干旱缺水,要满足钾盐开发,水资源必然成为了关键因素.因此,新疆水利厅组织科研人员对实地进行了考察,提出了把阿尔金山的水资源作为罗布泊钾盐矿水源的设想,初步拟定的两个引水方案进行了详细描述,并从工程地质条件、施工条件和工程技术可行性等方面进行了分析.最终认为两个方案工程地质条件和施工条件总体较优,工程技术上基本可行,主要总是在于对生态环境的影响和投资巨大.调用该水源极有可能对该区域生态环境造成不可逆转的影响.应采取的措施:(1)尽快在阿尔金山及羌塘高原区域建立水文、气象、生态等监测站点;(2)通过加大阿尔金山北麓水资源的开发力度来解决罗布泊钾盐矿近期工业用水需求,将阿尔金山及羌塘高原的水资源作为远期备用水源. 相似文献
10.