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本文根据黄陵地体、神农架地体和武当地体在沉积建造、岩石组合、变质作用、岩浆活动特点,现有同位素地质年龄及古地磁资料,进行了详细分析与区域性对比。并运用板块构造理论,对上述三个地体从元古代到中生代时期,在中国二个古板块运移过程中,它们发生离散和拼合的演化历史。还指出本区的地震活动带的分布,是受地体之间的沉陷带或地体内部深断裂的控制。 相似文献
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Diamond-bearing old sediments have so far been found at 24 localities distributed in 8 provinces or autonomous regions in China. They occur in 14 strata pertaining respectively to Tertiary, Cretaceous, Jurassic, Devonian, Cambrian, Precambrian, etc. Genetically, they might be grouped into four types: alluvial (fluvial), littoral, drift and karst sediments. The diamonds seem to have been derived from different sources: l) Diamonds in the Mesozoic-Cenozoic Sediments might have come directly from kimberlite nearby; 2) Diamonds formed during Precambrian period are widely distributed in sediments of various ages, i.e., from old strata to present rive bed deposits. As regards material resources, this type of diamonds can be traced to old primary deposits or might be attributed to repeated accumulation of this mineral from old to new strata. Isotope dating of kimberlite from various parts of the world indicate that a single intrusive or region is likely to have several groups of ages, suggesting the repetition and. long duration of magmatic activities of kimberlite. ln China, isotopic age values might likewise fall into nine groups: 70-135 m.y., 230-56 370 m.y., 400-530 m.y., 700 or 800-l000 m.y., 1010-1400 m.y., 1500 m.y., 1800- 2000 m.y. and >2000 m.y., denoting the existence of primary kimberlite deposits of various ages which provided material for diamond-bearing sediments in diverse strata. The emplacement of kimberlite in China, which took place mostly between Ordovician and Sinian, is called "apparent emplacement"; the emplacement reconstructed through an integrated study of the magmatic activity of kimberlite and the strata it intruded is called "actual emplacement"; and a unity linking these two emplacements by means of isotopic ages is termed "holoemplacement". These three emplacements are corrsepondent in time to "time of apparent emplacement:", "time of actual emplacement" and "time of holoemplacement" respectively to imply the long duration and repetition of the magmaitc activity of kimberlite. The diamond-bearing sediments are mostly scattered in strata of Mesozoic- Cenozoic Eras and Cambrian-Sinian Periods, in accord with "actual emplacement" and "apparent emplacement ,suggesting that diamonds came from kimberlite of two major periods. 相似文献
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周圣生,湖北省广济县(现武穴市)人,著名矿床地质学家。1944年毕业于中山大学地质系后,在湖南地质调查所工作。1949年后,历任湖北地质调查所地质矿产调查组负责人;中南地质调查所灵乡铁矿地质调查分队 相似文献
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湖北省地质学会于1964年元月3日至7日,在汉口召开第二届会员代表大会暨第一次学术年会。出席会议的代表、特邀代表和来宾共有100多人。在开幕式上,夏湘蓉副理事长作了关于湖北省地质研究发展简史,景才瑞理事作了关于第四纪冰川问题的演讲。 相似文献
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一、我国含金刚石古沉积层位 (一)第三系 1.山东某盆地北侧,下第三系官庄组砂砾岩和大汶口组石灰质砾岩、角砾岩中,含铬镁榴石,经对比与北侧产金刚石金伯利岩中的矿物特征一致。山东另一盆地以南地段,普遍发现含有金刚石的砾岩或砂砾岩块,充填于不同标高(80—540米)的寒武系、奥陶系石灰岩的裂隙、溶洞、溶沟中。含金刚石砾岩有90％以上见于中、上寒武统的岩溶负地形中,金 相似文献
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秦巴地区鄂西北地段,存在“武当地块”,为“四川陆核”东部的一个老地块。近年来广大地质工作者,特别是我队的同志获得大量资料,对地层、岩石、构造、地震及矿产等方面,各有所新的认识和发现,为了扩大找矿,开阔眼界,打开思路,对“武当地块”的成矿作用及成矿规律,试图作新的探索,有待进一步实践检验。对所引用资料的作者,谨致谢忱。一、本区地壳剖面与矿化界面 相似文献
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中国新石器时代绿松石文化 总被引：2，自引：0，他引：2
绿松石在中国文化、文明和传统起源过程中有着某种神秘而特殊的位置.新中国建国以来,数以千万个(次)考古发掘,出土了大量绿松石随葬器,并被视为国家保护文物.文物是历史的见证,是我国文明史的缩影和载体,是一部活生生的史书.这里仅就自数千件文献中收集到的绿松石遗存200余处进行分析. 相似文献
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