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The question of the stratigraphy of the Uralian and Permian has received in recent years much attention on the part of specialists from different continents of the Globe. This subject is also a sore and much discussed question for Russian geologists. (?)eologists of the country where these de(?)  相似文献   

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In this paper it is confirmed by means of study of the magnetic properties that the pebbles of igneous rock from the Eifelian conglomerates of the Pri-Polar Urals are derived from the platinum-bearing gabbro-peridotite formation and its age is established as Caledonian. In the author's opinion mass measurement of magnetic properties and statistical analysis of the results permits the use of comparison of the value of the vector of remanent magnetization as a supplementary criterion for age correlation of igneous rocks.  相似文献   

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玛克苏托夫 (Maksyutov)榴辉岩是乌拉尔—昆仑—祁连—秦岭—大别山元古代褶皱带之一部分。榴辉岩呈团块或布丁夹于片麻岩内 ,由于显生宙与花岗岩侵入有关的退变质叠加影响 ,时代变化自元古代至下古生代。榴辉岩矿物组分恒定但不同程度受绿帘蓝片岩相退变质叠加 ,榴辉岩中石榴石以富铁为主 (f=50 %~ 75% ) ;单斜辉石为绿辉石 Jd40 .3~ 52 .2。据 Krogh石榴子石—单斜辉石温度计 ,榴辉岩形成温度为 1 0 60~ 686℃ ,压力为 2 2 .3× 1 0 5~ 1 4.1 6× 1 0 5k Pa;PT轨迹具岩浆 (榴辉岩浆 )自上地幔向下地壳上侵的特点。  相似文献   

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新疆泥盆纪古地理   总被引:7,自引:2,他引:5  
王庆明 《新疆地质》2000,18(4):319-323
根据古地磁资料,泥盆纪时期除印度地块处于南半球10°~40°外,新疆境内其它块体均处于北半球0°~35°,位置变化不大。西伯利亚、准噶尔和塔里木3大地块向北漂移,华北地块基本未动,华南地块、印度地块和柴达木断块向南漂移。 晚古生代时,形成阿尔泰泥盆纪弧后拉张裂谷,发育一套细碧-角斑岩建造。在准噶尔地块中,形成了谢米斯台-淖毛湖晚古生代岛弧、弧间盆地和萨吾尔晚古生代岛弧。塔里木北缘的南天山南缘洋盆,形成哈尔克山、艾尔宾山南缘断续的火山岛弧带。塔里木古陆区处于区域挤压背景,海水自东向西大规模退缩,形成一套陆…  相似文献   

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《International Geology Review》2012,54(12):1659-1669
The suture line terminology of Noetling, Wedekind, and Schindewolf is critically summarized and Ruzhentsev's recently proposed nomenclature is supported. For the ceratite and ammonite orders the author advocates a genetic terminology in which the so-called principal lateral lobe is regarded as the primary umbilical lobe.-- E. T. Tozer.  相似文献   

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《International Geology Review》2012,54(12):1561-1581
Landscape-geochemical analysis of the expressions of blind ore bodies, in the semi-arid grassland environments of the Southern Urals, shows a depression of the migration capacities of copper, nickel, and cobalt and a relative weakness of the corresponding secondary dispersion halos in the geochemical profiles. Such halos are derived from the ore bodies' mineralized host rocks, however, rather than from the ore bodies themselves, in ortho-eluvial and trans-ortho-eluvial landscapes, and, as such, have a certain prospecting usefulness, under the circumstances, particularly where they lie in immature soils or in certain horizons of thin chernozems typical of the region. On the other hand, geochemical prospecting in neo-eluvial landscapes of the area is definitely not recommended. Mechanical dispersion halos and trains are the principal forms of the metals' migration in the region but they too represent mainly the anomalous disseminated mineralization in the host rocks, right next to the ore bodies themselves.--V. P. Sokoloff.  相似文献   

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The western and north-eastern parts of Shansi Province are districts of typical development of the oldest Pre-Palaeozoic formations. In western Shans these formations are well exposed in the territory midway between the Taiyuan plain and the Yellow River and are bordered on almost all sides by the so-called Shansi Formation of late Palaeozoic age. Near the margin the area of oldest  相似文献   

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The western and north-eastern parts of Shansi Province are districts of typical development of the oldest Pre-Palaeozoic formations. In western Shans these formations are well exposed in the territory midway between the Taiyuan plain and the Yellow River and are bordered on almost all sides by the so-called Shansi Formation of late Palaeozoic age. Near the margin the area of oldest  相似文献   

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一、前言湖南泥盆系除下统、中统跳马涧组未见珊瑚化石外,自中统棋子桥组至上统锡矿山组均有产出。其中棋子桥组和余田桥组尤为发育,其丰富、完美程度为华南地区所罕见。是研究南方泥盆纪珊瑚化石及其地层的理想地区之一。湖南晚泥盆世地层素有“湖南统”之称。  相似文献   

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Ammonoids of early Upper Scythian age are described from three localities in the Northern Caucasus. No data on relative stratigraphic position is given, but some forms are common to the different exposures and the author concludes that all the ammonoids are Upper Scythian (Olenekian). Affinites with Pacific faunas are stressed and the faunules are correlated with the Owenites zone of North America. Two new genera (Parinyoites and Subowenites) and three new species (Dieneroceras caucasicum, Parinyoites ,mastykensis, Subovvenites slavini)are proposed. Flemingites pulcher Waagen, Wyomingites aplanatus (White), Parussuria compressa (Hyatt and Smith), and Owenites koeneni (Hyatt and Smith) are described and figured. Parinyoites differs from Metinyoites in having rounded saddles and it lacks the keel and costation of Inyoites. Subowenites has reticulate ornamentation, unlike Owenites, Parowenites, and Pseudowenites; it also lacks the adventive notches in the median saddle of Pseudowenites. --E. T. Tozer.  相似文献   

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