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1.
The stratigraphically oldest remains of ornithomimid theropod dinosaurs are known from the Cenomanian Khodzhakul Formation and the Turonian Bissekty Formation of Uzbekistan. The ornithomimid from the Bissekty Formation is documented by more than 800 isolated bones that represent much of the skeleton. It shows at least three unambiguous synapomorphies of Ornithomimidae: length of anterior cervical centra three to five times greater than transverse width; low and rounded fibular crest of tibia; metatarsal III pinched between metatarsals II and IV; and proximal end of metatarsal III not visible in anterior view. Phylogenetic analysis, based on a dataset with 568 morphological characters and including all known ornithomimosaurian taxa, places the ornithomimid from the Bissekty Formation near the base of the ornithomimid radiation, between Archaeornithomimus asiaticus and Sinornithomimus dongi.  相似文献   
2.
Muruntau金矿床位于乌兹别克斯坦卡拉库姆板块北缘,是世界规模最大的金矿床。赋矿地层为一套发生绿片岩相浅变质作用的含炭复理石建造。矿区主要经历了四期变形变质作用(D1-D4),矿体受构造控制明显,就位于桑格龙套-塔姆德套与穆龙套-道古兹套剪切带的构造交汇部位,金矿化主要产于次级韧脆性断裂中。对矿床的矿石硫化物及地层开展了系统S、Pb同位素研究,结果表明石英脉型及蚀变岩型矿石中硫化物的δ34S变化范围较大,集中于2.2‰~6.1‰,其中蚀变岩型矿石中毒砂样品δ34S值集中于2.2‰~4.6‰,含金石英脉中硫化物样品δ34S值集中于3.0‰~6.1‰,方解石-石英脉中硫化物样品δ34S值集中于3.5‰~4.0‰,表明矿石中硫主要来源于地层,可能有少量岩浆硫加入。2件黑色页岩中毒砂206Pb/~(204)Pb为19.906~20.378,~(207)Pb/~(204)Pb为15.730~15.750,208Pb/~(204)Pb为38.388~39.894;3件含金石英脉中黄铁矿206Pb/~(204)Pb为18.848~19.431,~(207)Pb/~(204)Pb为15.669~15.736,208Pb/~(204)Pb为38.346~38.879;2件方解石脉中毒砂206Pb/~(204)Pb为18.715~19.563,~(207)Pb/~(204)Pb为15.639~15.740,208Pb/~(204)Pb为38.640~39.295。6件地层岩石样品的铅同位素组成206Pb/~(204)Pb为19.416~20.600,~(207)Pb/~(204)Pb为15.675~15.746,208Pb/~(204)Pb为38.876~39.431。矿石铅与地层铅均落于上地壳与造山带之间,矿石铅显示较大的跨度,且与地层岩石铅具有部分重合,显示成矿物质具有双重来源,与赋矿地层及造山期变质流体均表现出密切成因联系。结合矿床地质特征总结分析,沉积地层的物质准备+多期构造运动驱动变质流体运移(D1-D4)+岩浆热液的后期叠加应该是Muruntau巨量金属富集的关键控制因素。  相似文献   
3.
In this paper we describe previously unpublished trionychid turtle material, consisting of skull fragments, from the Late Cretaceous (late Turonian) Bissekty Formation of the Dzharakuduk locality in Uzbekistan. This material is assigned to two taxa: the skull-based Khunnuchelys kizylkumensis Brinkman et al. (1993, Can. J. Earth Sci. 30, 2214-2223) and Trionychini indet. Two specimens which cannot be confidently attributed to these two taxa are considered Trionychidae indet. In addition to these trionychid taxa known from skulls, the Dzharakuduk turtle assemblage includes at least two shell-based taxa, Aspideretoides cf. A. riabinini and “Trionyx” cf. “T.” kansaiensis. For this and other Late Cretaceous localities of Middle Asia and Kazakhstan, we suggest the probable skull-shell associations of Khunnuchelys spp. with “Trionyxkansaiensis-like forms and Trionychini indet. with Aspideretoides-like forms.  相似文献   
4.
Food resources play a great role in human livelihood, so it is meaningful to investigate their utilization and structural evolution, especially in developing countries. This study takes data from FAOSTAT and the World Bank, and applies the emergy method to analyze Uzbek food consumption changes and characteristics from 1992 to 2019. Two main results were obtained: (1) National food consumption showed a persistent increase and had a remarkable change in stages, with the first stage of low-level repetition, the second stage of speeding up and the third stage of high development. The increase of animal-based food consumption was more notable than that of plant-based food consumption. (2) Per capita annual food consumption had a tendency of change that was similar to that of national food consumption. The proportion of animal-based food in the total per capita annual food consumption usually remained about 2-fold higher than that of plant-based food consumption. The main food consumption pattern was the combination of crops such as wheat and rice with meat such as beef. The fruit and vegetable consumption also increased. With the growing population, various changes in food demand will inevitably happen, so it is necessary to take sustainable measures in time to satisfy the new demand and to protect resources and the environment.  相似文献   
5.
乌兹别克斯坦的金矿资源十分丰富,其储量居世界第4位,产量居世界第8位。位于乌兹别克斯坦中部的克孜尔库姆地区是世界最大的金矿省之一。闻名世界的穆龙套金矿床就产在这里。乌兹别克斯坦的内生金矿床主要有4个工业-成因类型:金-石英型、金-硫化物-石英型、金-硫化物型和金-银-石英型。前三个类型统称之为克孜尔库姆型,穆龙套金矿床属于这个类型。本文重点讨论了克孜尔库姆型金矿床的成因问题。  相似文献   
6.
叶小伟  乔建芳 《干旱区地理》2022,45(4):1313-1319
乌兹别克斯坦是位于中亚腹地的“双内陆国”,是古代丝绸之路沿线的重要国家之一。针对“一带一路”倡议实施框架内中国与乌兹别克斯坦在可再生能源领域合作的需要,利用文献、数据等分析法,从太阳能、水能、风能、地热能、沼气能等可再生能源的发展现状、国家发展规划、优惠激励措施和可再生能源领域的最新投资项目等角度,对乌兹别克斯坦可再生能源发展总体情况和需求进行了分析。结果表明:乌兹别克斯坦拥有良好的可再生资源条件,未来可再生能源利用比例也将逐渐提高。近年来,乌兹别克斯坦政府高度重视可再生能源发展,接连出台有关政策,大力推进可再生能源发电项目建设,以期实现能源多样化。中乌可再生能源利用领域合作前景广阔,双方在人才、技术、资金、设备等方面合作空间巨大,在提高可再生能源利用效率、发展绿色经济和开展低碳能源合作领域将大有作为。  相似文献   
7.
新疆西天山斑岩铜矿找矿勘查备受关注。乌兹别克斯坦Almalyk斑岩铜矿田处在西天山西段,铜矿规模属亚洲第二大,但其成矿时代还没有准确厘定。在区域地质构造中,Almalyk铜矿田位于中天山加里东—华力西褶皱带南部边缘,包括Kalmakyr、Dalneye、Sarcheku和Kyzata等4个铜矿床,铜成矿主要发生在斑岩体内,原生矿石呈网脉状、浸染状,金属矿物主要有黄铁矿、黄铜矿,辉钼矿、赤铁矿、磁铁矿、自然金、斑铜矿等。针对Sarcheku铜钼矿石中辉钼矿利用Re-Os法测得(320.4±2.3)Ma的模式年龄和(317.6±2.5)Ma的等时线年龄。结合岩浆建造序列,认为矿田内构造—岩浆—热液过程开始于早石炭世,发展于晚石炭世,结束于早二叠世,斑岩型铜成矿主要在晚石炭世。西天山包括Almalyk铜矿田在内大型—超大型斑岩型铜成矿作用主要在中泥盆—晚石炭世(D2—C2),与古亚洲洋壳向哈萨克斯坦—伊犁板块之下俯冲形成的复杂岛弧岩浆地质过程有关。  相似文献   
8.
介绍了乌兹别克斯坦共和国的地质构造背景,已探明的和潜在的矿产资源,投资环境及可供我国利用的矿产资源。乌兹别克斯坦共和国是我国的近邻,其金,铀,钾盐,银,铜是乌兹别克斯坦的优势和矿产资源,尤其是金和铀的储量与产量在世界上占有重要的地位,应当在我国矿产资源的全球战略中占据它应有的位置。  相似文献   
9.
The Jurassic Angren coal–kaolin deposit, Uzbekistan, is one of the largest producers of coal and kaolin suitable for refractories and industrial ceramics in central Asia. The Major coal seam, attaining a thickness between 4 and 24 m, is encased by kaolin-bearing bedsets which have been derived from supergene pre- and hypogene post coal kaolinization. Joint clay-mineralogical and coal petrographic analyses formed the basis of the environment analysis of this coal–kaolin series and constrained the physico-chemical conditions existing during the Triassic through Jurassic period of time. Massive kaolin I underneath the coal seam is a typical residual kaolin or underclay with arsenic Fe-disulfides and siderite indicative of a reducing swampy depositional environment developing under moderately hot climatic conditions. Towards the top, kaolin I became reworked fluvial by processes. The Major coal seam developed in swamps interfingering with a fluvial drainage system of suspended to mixed-load deposits. The maximum temperature for the post-depositional alteration of the carbonaceous material is 70 °C. Post-coal kaolinization (kaolin II) affecting trachyandesites and trachytes is of low-temperature origin and low-sulphidation-type. The temperature of formation was well below 200 °C, deduced from the absence of dickite in the clay mineral assemblage. Basaltic dykes intersected the coal–kaolin series and account for contact metamorphic reactions in the proximal parts of the aluminum-bearing wall rocks reaching sanidinite-facies conditions with temperatures around 1000 °C.  相似文献   
10.
To date three taxa of troodontid theropod dinosaurs have been recognized from Upper Cretaceous strata in two regions of the Kyzylkum Desert in Uzbekistan. The Cenomanian Khodzhakul Formation in the southwestern Kyzylkum Desert has yielded isolated serrated teeth and some postcranial bones of an indeterminate troodontid. In the central Kyzylkum Desert troodontids are known from the Cenomanian Dzharakuduk Formation (Urbacodon itemirensis) and the Turonian Bissekty Formation (Urbacodon sp.). Urbacodon itemirensis is known from a single dentary whereas Urbacodon sp. is represented by isolated teeth, maxilla and dentary fragments, a partial braincase, and some postcranial bones. The troodontid affinities of Urbacodon are supported by several synapomorphies: presence of a subotic recess; reduced basal tubera placed directly under the occipital condyle; maxilla participating in the margin of the external naris; nutrient foramina on dentary situated within a deep lateral groove; dentary without distinct interdental plates; large number of small dentary and maxillary teeth; teeth constricted between root and crown; anterior dentary teeth smaller, more numerous, more closely spaced than those in the middle of the tooth row, and implanted in a groove; posterior dorsal vertebrae with tall and posterodorsally tapering neural spines; and presence of a midline sulcus on the neural arches of distal caudals. Among Troodontidae, Urbacodon resembles Byronosaurus, Gobivenator, and Xixiasaurus in the absence of serrations on the tooth crowns and having premaxillary teeth that are D-shaped in cross-section. However, phylogenetic analysis did not recover a clade of Asiatic troodontids with unserrated teeth.  相似文献   
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