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金刚石及其寄主岩石是人类认识地球深部物质组成和性质、壳幔和核幔物质循环重要研究对象。本文总结了中国不同金刚石类型的分布,着重对比了博茨瓦纳和中国含金刚石金伯利岩的地质特征,取得如下认识:(1)博茨瓦纳含矿原生岩石仅为金伯利岩,而中国含矿岩石成分复杂,金伯利岩主要出露在华北克拉通,展布于郯庐、华北中央和华北北缘金伯利岩带,具有工业价值的蒙阴和瓦房店矿床分布于郯庐金伯利岩带中;钾镁煌斑岩主要出露在华南克拉通,重点分布在江南和华南北缘钾镁煌斑岩带中;(2)钙钛矿原位U-Pb年龄和Sr、Nd同位素显示,86～97 Ma奥拉帕金伯利岩群和456～470 Ma蒙阴和瓦房店金伯利岩均具有低87Sr/86Sr(0.703～0.705)和中等εNd(t)(-0.09～+5)特征,指示金伯利岩浆源自弱亏损地幔或初始地幔源区;(3)博茨瓦纳金伯利岩体绝大多数以岩筒产出,而中国以脉状为主岩筒次之;博茨瓦纳岩筒绝大部分为火山口相,中国均为根部相,岩筒地表面积普遍小于前者;(4)奥拉帕A/K1和朱瓦能金伯利岩体是世界上为数不多的主要产出榴辉岩捕虏体和E型金刚石的岩筒之一,而同位于奥拉帕岩群的莱特拉卡内、丹姆沙和卡罗韦岩体与我国郯庐带的金伯利岩体类似,均主要产出地幔橄榄岩捕虏体以及P型和E型金刚石;(5)寻找含矿金伯利岩重点注意以下几点:克拉通内部和周缘深大断裂带是重要的控岩构造;镁铝榴石、镁钛铁矿、铬透辉石、铬尖晶石和铬金红石等是寻找含金刚石金伯利岩重要的指示矿物;航磁等地球物理测量需与土壤取样找矿方法相结合才能取得更好效果;(6)郯庐金伯利岩带、江南钾镁煌斑岩带和塔里木地块是中国重要含矿岩石的找矿靶区,冲积型金刚石成矿潜力巨大。 相似文献
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《矿物学报》2016,(3)
河南鹤壁地区位于太行山构造带上,该区金伯利岩中的地幔包体携带有岩石圈地幔的丰富信息。本文报道了石榴石二辉橄榄岩包体中的镁橄榄石和镁铝榴石的矿物化学特征。金伯利岩中地幔包体的镁橄榄石I(Mg~#)为91.7±0.2(n=69)。与鹤壁地区尖晶石相方辉橄榄岩相比,I(Mg~#)略偏小,指示二辉橄榄岩经历的熔融程度较低,具有过渡型地幔的特征。根据Cr_2O_3含量,镁铝榴石可以划分为高铬系列和低铬系列两类。橄榄石-石榴石矿物温压计计算表明,包体压力在1.7~2.5 GPa之间(55~80 km),温度在641~1055℃之间,对应的大地热流值为50~60m W/m~2,甚至更高。指示金伯利岩侵位时对应于较高的大地热流条件。根据Grutter的镁铝榴石划分方案,镁铝榴石主要划分为G9型、G3和G4型,其中G3和G4型镁铝榴石记录了岩石圈地幔被交代的过程。根据温压条件及岩石圈地幔性质,可以认为鹤壁地区不具有形成金刚石矿的深部地质条件。 相似文献
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金刚石包裹体矿物化学特征与华北东部克拉通岩石圈地幔属性 总被引：2，自引：0，他引：2
华北地台金刚石的包裹体中含有丰富的地幔信息.对山东蒙阴、辽宁复县两地金刚石中包裹体矿物包括橄榄石、石榴石、单斜辉石和铬铁矿的化学成分进行了深入分析,金刚石包裹体矿物的主量元素显示华北地台至少在古生代金伯利岩侵位时具高度亏损玄武质的难熔克拉通岩石圈地幔特征.应用适用于石榴石橄榄岩相的单斜辉石温压计对金刚石包裹体中透辉石进行了计算,得出华北地台金刚石形成于1 083～1 194℃、5.3-6.1 GPa的地质环境下.蒙阴和复县两地金刚石包裹体所反映的古老岩石圈地幔虽然都表现为克拉通岩石圈地幔特征,但也存在一定的不均一性.同时,通过对华北东部古生代与新生代地幔矿物的主量元素及地幔热状态的对比,结合现有的地幔岩石学和地幔地球化学的研究成果,认为软流圈物质对古老岩石圈地幔的侵蚀作用能较好地解释华北岩石圈减薄. 相似文献
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金伯利岩型金刚石原生矿床含矿性评价是了解金刚石成矿规律和指导区域性找矿的重要依据。华北克拉通是我国重要的金刚石成矿远景区,目前已发现了两个重要的含金刚石金伯利岩岩区（山东蒙阴和辽宁瓦房店）。近年来,对岩区内不同品位金刚石典型矿床的研究表明金伯利岩中的金刚石品位取决于以下两个重要的地质过程：金伯利岩岩浆对金刚石的捕获作用和金伯利岩岩浆对金刚石的熔蚀作用。在华北克拉通下方存在一个金刚石稳定区,温度为950~1200 ℃,压力为4. 4~6. 1 GPa。山东蒙阴和辽宁瓦房店金伯利岩岩浆在上升过程中穿过该区域并捕获其中的金刚石,成为含矿岩浆;而铁岭和鹤县等金伯利岩岩浆在上升过程中不穿过该区域,成为不含矿岩浆。在穿过金刚石稳定区时,富矿的金伯利岩捕获了更多的金刚石以及金刚石的伴生指示矿物（如镁铝榴石,镁铬铁矿）;而贫矿的金伯利岩则相对捕获了少量的金刚石和指示矿物。这些指示矿物往往参加了金刚石的形成过程,有些作为缓冲剂控制了反应（岩浆或熔体）的氧化还原状态,有些则作为反应物或者生成物参与到反应中。部分指示矿物（如镁铝榴石）还进一步地记录了金刚石形成后金伯利岩岩浆对金刚石的交代作用。金伯利岩岩浆温度（T）,氧逸度（fO2）和挥发份(H2O和CO2)均会对金刚石的熔蚀作用产生影响,其中氧逸度作用最大,温度次之,而挥发份作用最弱。在华北克拉通,金伯利岩中指示矿物（镁铝榴石、镁铬铁矿）和金伯利岩岩浆特征（温度,氧逸度和挥发份）共同组成了金伯利岩型金刚石原生矿的评价指标。 相似文献
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镁铝榴石是贯穿整个地幔的重要组成矿物之一 ,携带着丰富的地幔甚至核幔边界信息。其中的包裹体是源于地幔深部最直接的样品。(1)样品描述 :镁铝榴石样品采自山东蒙阴富含金刚石的胜利一号金伯利岩岩管 ,近似椭圆形外观 ,长约 2 3mm ,最宽处约 16mm ,厚约 8mm ,主体为紫红色 ,沿裂隙有暗色的充填物。存在于镁铝榴石中的两个含有包括钾硼氯包裹体在内的多个无氧物相 (图 1和图 2中黑色部分 ,将另文讨论 )图 1 球状体背散射电子图像图 2 半球状体背散射电子图像的球状体 ,均于主晶镁铝榴石中呈清晰轮廓。球状体的主体成分为含水或其它挥发份… 相似文献
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郯庐断裂带是太平洋西岸的中国东部乃至东北亚最重要的一条深断裂带,影响着中国东部的岩浆活动和有关固体矿产（金多金属、金刚石等）和能源（油气）的产出。该断裂的山东段被称为沂沭断裂带,其东侧的胶东金矿带是中国最重要的金矿床集中区,西侧则分布有金刚石（蒙阴金伯利岩群）、石油（胜利油田）等资源- 能源,其研究的理论意义和经济意义重大。借助于场发射扫描电镜支持下的自动矿物识别表征系统（AMICS）,笔者从郯庐断裂带西侧的深部岩浆岩（金伯利岩和碳酸岩- 碱性杂岩）矿物组合中,识别出具有标志性的矿物组合,主要包括：① 金伯利岩的典型矿物组合为镁铝榴石- 钙铁榴石- 钙钛矿- 金云母- 磁铁矿- 铬铁矿±斜硅镁石±自然硅±金刚石等,并首次观察到自然硅,蚀变矿物组合——金云母- 富钛磁铁矿- 钛铁矿- 富钛尖晶石- 绿泥石等,这种矿物组合充分反映了较为还原的深部流体条件;② 碱性杂岩的典型矿物组合——方解石- 氟碳铈矿- 氟碳钙铈矿,叠加改造矿物组合——重晶石- 天青石- 白云石等。在碱性杂岩中,还观察到黄铁矿中含有异常高的深源的稀贵金属元素（Au、Co、Pt、Ru、Os、Ir、 Re等）。郯庐断裂带山东段（沂沭断裂带）岩浆岩中深部来源的矿物组合特征,为矿床成因研究和深部资源探测提供了重要信息。 相似文献
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《矿物岩石地球化学通报》2016,(6)
与金刚石伴生的尖晶石,常作为指示矿物来评价金伯利岩的含矿性。为了解瓦房店30号岩管金伯利岩中尖晶石特征,本文对其进行了细致的形态学观察和电子探针分析。结果表明,尖晶石呈椭圆状-次棱角状,粒径大(500~1000μm),部分被熔蚀成港湾状。尖晶石中Cr_2O_3(最高达66.56%)和MgO(8.88%~16.68%)含量高,Ti含量低(大部分1%),为镁铬铁矿。尖晶石成分变化受Al~(3+)-Cr~(3+)类质同象作用控制。尖晶石为地幔捕掳晶,原地幔岩为橄榄岩。尖晶石成分特征表明30号岩管金伯利岩具有一定地携带金刚石的能力,但与50号岩管和蒙阴常马庄金伯利岩相比,30号岩管金伯利岩金刚石含矿性弱。 相似文献
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我国金伯利岩中镁铝榴石的化学成分特征及找矿意义 总被引：1，自引：0，他引：1
镁铝榴石是金刚石的重要伴生矿物,而在许多非金伯利岩中也含有镁铝榴石,因此深入研究金伯利岩中与非金伯利岩中镁铝榴石的物理、化学特征,找出它们之间的差异进而确立金伯利岩中镁铝榴石的标型特征,对利用重砂法寻找金刚石原生矿具有重要意义。本文仅对我国已发现的金伯利岩中镁铝榴石的化学成分特征及与非金伯利岩中镁铝 相似文献
11.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
13.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.) 相似文献
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正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology, 相似文献
18.
正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.) 相似文献
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正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se- 相似文献
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正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with 相似文献