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赋存于花岗岩中的金矿床在我国金矿资源中的地位极其重要，并形成我国独具特色的金矿类型。我国含金花岗岩的时代，绝大多数为燕山期，其次是华力西-印支期及加里东期；含金花岗岩体分布广泛，特别集中出露在中朝板块东缘的胶东地体内和北缘广大地区，在北方陆壳增生区及华南扬子板块内亦有分布；研究表明，含金花岗岩类以Ⅰ型花岗岩为主，其次是A型和S型；在同一地区含金花岗岩的金丰度明显高于不含金花岗岩。 相似文献
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内蒙古海拉尔盆地大磨拐河组孢粉组合 总被引：13，自引：1，他引：13
海拉尔盆地大磨拐河组自下而上可以划分出两个孢粉组合 :哈氏三角孢 -微细云杉粉 ( Deltoidospora hallii-Piceaepollenites exilioides)组合和澳洲无突肋纹孢 -卵形光面单缝孢 ( Cicatricosisporites australiensis- L aevigato-sporites ovatus)组合 ,分别分布于大磨拐河组一段和二段 ,组合特征明显 ,可以作为研究区内地层划分对比的生物地层学依据之一。两个孢粉组合中见有属种繁多的海金沙科孢子及其他繁盛于早白垩世的孢子花粉 ,结合在数以千计的岩心样品中没有发现可靠的早期被子植物花粉的情况分析 ,推测产这两个孢粉组合的大磨拐河组的地质时代为早白垩世凡兰吟期—欧特里沃期 ( Valanginian— Hauterivian) ,不排除部分进入巴列姆期 ( Barrem ian)的可能 相似文献
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江西冷水坑银铅锌矿田构造地球化学的若干问题 总被引：5，自引：0，他引：5
本文重点对冷水坑银铅锌矿田构造发育特征和构造地球化学的若干问题进行了初步探讨。运用裂隙统计、显微构造和组构分析方法对矿田NE向、NW向和近EW向断裂的力学性质和活动方式作了概略性论述。研究了银路岭矿床三个构造地球化学剖面的分析结果,其中主要成矿元素和伴生元素的分布和丰度变化与构造发育的关系,显示出本区构造地球化学场具有一定的分布规律。矿田F_1断裂是有一定区域意义的重要的成岩成矿和控岩控矿断裂,本次工作中选择了茶田剖面对F_1断裂带构造地球化学特征进行了初步探讨。 相似文献
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柴达木盆地震旦纪-三叠纪构造演化经历了2 个一级构造旋回,即震旦纪-中泥盆世开合旋回和晚泥盆世-三叠纪开合旋回,它们与祁连洋、赛什腾-锡铁山洋、昆仑洋和阿尔金洋在不同阶段伸展张裂、俯冲消减和闭合作用有关,其分划性时间界面分别为800Ma、377 Ma 和208 Ma,时间跨度分别为423 Ma 和169 Ma.第一个旋回自震旦纪开始张裂,柴达木形成大陆裂谷盆地;寒武纪-中奥陶世伸展为被动大陆边缘,柴达木表现为克拉通内(伸展)盆地;晚奥陶世开始俯冲消减,泥盆纪晚期碰撞闭合,柴达木形成克拉通内(挤压)盆地。第二个旋回表现为海西-印支期与南昆仑洋有关的弧后拉张-弧后造山事件,柴达木在晚泥盆世-早二叠世形成弧后裂陷盆地,晚二叠世-三叠纪形成弧后前陆盆地。在两个开合旋回的末期,均发生大规模盆地反转作用,导致柴达木及邻区构造格局、海陆分布和沉积特征发生根本变化。 相似文献
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海拉尔盆地海参1井伊敏组孢粉组合的地层意义 总被引：3，自引：0，他引：3
海参1井伊敏组孢粉化石异常丰富,自下而上可以划分出3个孢粉组合:Impardecispora-Cyathidites-Clavatipollenites组合,Stereisporites-Deltoidospora-Asteropollis组合,Appendicisporites-Asteropollis-Tricolpites组合,分别分布于伊敏组一段、二段和三段,组合特征明显,是海拉尔盆地乌尔逊凹陷划分伊敏组与大磨拐河组的重要生物依据之一,更是伊敏组内三段划分和井间对比的生物依据之一。3个孢粉组合中见有属种繁多的海金沙科孢子及其他繁盛于早白垩世中晚期的孢子花粉,结合在绝大多数样品中发现的早期被子植物花粉的情况分析,推测含这3个孢粉组合的伊敏组地质时代为早白垩世巴列姆期—早阿尔必期(Barremian—Early Albian)。 相似文献
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通过野外地质调查及对各断陷典型地震剖面和构造发育史剖面的综合研究,系统探讨了研究区深大断裂对断陷盆地群的控制作用。以西拉木伦河-长春-延吉板块拼接带、赤峰-开原超岩石圈断裂为边界,将研究区自南向北分为辽西盆地区、辽北盆地区和吉西盆地区等3个一级构造分区;根据控盆断裂及其断陷盆地群的时空分布、断陷构造样式、不同时期伸展量等特征将辽北盆地区分为西部、中西部、中东部等3个二级断陷区。西拉木伦河断裂控制了西部区断陷的形成和分布;嫩江—八里罕断裂和孙吴—大庆—阜新断裂对中西部断陷区的控盆效应大体相近;孙吴—大庆—阜新断裂与佳木斯—伊通断裂共同对中东部断陷区起着重要的控制作用;昌图断陷主要受佳木斯—伊通断裂所控制。辽北盆地区主要表现为双断式地堑,断陷群的形成和分布不仅受北北东向断裂控制,也受到近东西向的西拉木伦河断裂和赤峰—开原断裂重新活动的控制。中西部断陷区伸展率具有从九佛堂组沉积期—沙海组沉积期—阜新组沉积期依次减小的变化规律。中东部断陷区与中西部断陷区存在明显差异,NNE向与近EW向深大断裂对两区构造分区控制程度不同。 相似文献
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We report equilibrium sapphirine t quartz assemblage in biotiteeorthopyroxeneegarnet
granulites from a new locality in Panasapattu of Paderu region in the Eastern Ghats granulite belt, which
provide new evidence for ultrahigh-temperature (UHT) metamorphism at 1030e1050 C and 10 kbar in
this region. The development of migmatitic texture, stabilization of the garneteorthopyroxenee
plagioclaseeK-feldspar association, prograde biotite inclusions within garnet and sapphirine as well as
sapphirine and cordierite inclusions within garnet in these granulites indicate that the observed peak
assemblages probably formed during prograde dehydration melting of a BteSilleQtz assemblage, and
constrain the prograde stage of the PeT path. The core domains of orthopyroxene porphyroblasts have
up to wt(Al2O3) 9.6%, which suggest that the temperatures reached up to 1150 C suggesting extreme
crustal metamorphism. These conditions were also confirmed by the garneteorthopyroxene thermobarometery,
which yields a PeT range of 1012e960 C and 9.4 kbar. The PeT phase topologies computed
using isochemical sections calculated in the model system Na2OeCaOeK2OeFeOeMgOeAl2O3eSiO2
eH2O (NCKFMASH) for metapelites, garnet-free sapphirine granulites and garnet-bearing sapphirine
granulites match the melt-bearing assemblages observed in these rocks. Isochemical sections constructed in the NCKFMASH system for an average sub-aluminous metapelite bulk composition, and contoured for
modal proportions of melt and garnet, as well as for the compositional isopleths of garnet, predict phase
and reaction relations that are consistent with those observed in the rocks. Garnet and orthopyroxene
contain Ti-rich phlogopite inclusions, suggesting formation by prograde melting reactions at the expense
of phlogopite during ultrahigh-temperature conditions. These PeT results underestimate ‘peak’ conditions,
in part as a result of the modification of garnet compositions in the domains where some melt
was retained. The post-peak evolution is constrained by a succession of melt-present reactions that occur
at P < 10 kbar, inferred from micro-structural relations among various minerals. After high-temperature
decompression from the metamorphic peak, the PeT path followed a near isobaric cooling stage to
T < 900 C. The UHT rocks investigated in this study occur within a continental collision suture which
witnessed prolonged subductioneaccretion history prior to the final collision. We correlate the extreme
metamorphism and the stabilization of UHT mineral assemblages to heat and volatile input from an
upwelled asthenosphere during subductionecollision tectonics in a Proterozoic convergent plate margin. 相似文献
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塔里木多旋回盆地复合构造样式初步分析 总被引：20，自引：10，他引：10
塔里木盆地多旋回的演化历史导致了多期次的复合构造变形作用。不同方式的构造运动导致了不同方式的复合,不同等级和不同规模的变形叠加导致了不同级次的复合构造。根据造成复合构造的应力场变化的特征,结合具体实例将塔里木盆地复合构造划分为8种主要类型:继承性挤压、继承性走滑、挤压--走滑、走滑--挤压、拉张--挤压、挤压--拉张、挤压--重力和重力--挤压复合构造。复合构造为油气运移提供了新的运移动力场及高效输导体系。构造复合一方面可能会加大早期构造的幅度并使其更为复杂,另一方面会导致各种圈闭更为复杂的平面组合与纵向叠置方式。构造复合对早期已聚集的油气存在一定的破坏作用,同时,由多油源、多期生烃、多通道、多圈闭类型和多成藏期组成的成藏条件也在复合构造中形成了以塔河--轮南特大型油气田为代表的复式油气聚集带。 相似文献
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马厂箐矿集区铜、钼、金矿化之间的关系对于认识该矿床的成矿作用过程及地质勘查具有重要意义。利用40Ar-39Ar同位素定年方法对乱硐山矿段夕卡岩型铜钼金矿化和人头箐矿段蚀变岩型金矿石中热液白云母进行同位素定年,得到夕卡岩化矿石中白云母样品(B119)40Ar-39Ar坪年龄为35.25±0.36Ma,等时线年龄为35.0±1.8Ma,反等时线年龄为34.8±1.9Ma。蚀变岩型金矿化矿石中白云母样品(B118)40Ar-39Ar坪年龄为35.35±0.32Ma,等时线年龄为34.44±0.99Ma,反等时线年龄为34.4±1.2Ma。这与正长斑岩(35.6±0.3Ma)、花岗斑岩(35.0±0.2Ma)、斑岩型铜钼矿化成矿年龄(35.8±1.6Ma)和(33.9±1.1Ma)较为一致,显示马厂箐铜钼金矿床与正长(斑)岩+二长(斑)岩+花岗斑岩+斑状花岗岩岩性组合有关,铜钼金成矿属于同一个构造—岩浆—成矿系统的产物。 相似文献
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内蒙古阿巴嘎旗奥陶纪岩体的发现及地质意义 总被引：4，自引：0，他引：4
阿巴嘎旗格日敖包岩体位于贺根山断裂带北侧,为一个复式岩体,由石英闪长岩、花岗闪长岩和黑云母二长花岗岩组成,主体为二长花岗岩。采用LA--MC--ICP--MS 锆石U--Pb 定年方法,获得黑云母二长花岗岩206Pb /238U 年龄为449 ± 3. 0 Ma,形成时代为晚奥陶世。岩石为高钾钙碱性系列,轻稀土富集,微量元素Ba、Sr、Nb、Ta 、P、Ti 亏损,Rb 、Th、U、K、Nd、Zr 等元素富集,表明其形成于活动大陆边缘环境。其形成可能与苏尼特左旗南侧俯冲事件有关。 相似文献
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Petrology, Metamorphic Process and Genesis of The Dabie--Sulu Eclogite Belt, Eastern--Central China 总被引：10，自引：0，他引：10
Zhang Zeming You Zhendong Han Yujing Sang Longkang Department of Earth Sciences China University of Geosciences Wuhan Hubei 《《地质学报》英文版》1996,70(2):134-156
The Qinling-Dabie-Sulu high-pressure and ultra-high pressure metamorphic belt wasformed by subduction and collision between the North China and Yangtze plates. The study ofthe eclogite belt is very important in understanding the evolution of the Qinling Dabie orogen. Inthe present paper the geology, petrology, minerology and chronology of the eclogites in the Dabieand Sulu areas are described. The principal conclusions of this work are as follows: (1) Based up-on the field occurrence and the P-T conditions of the eclogites, two types of eclogite can be dis-tinguished: Type 1—the low-temperature and high-pressure eclogite in the mid-late Proterozoicmetamorphic series, and Type 2—the ultra-high pressure eclogite in the late Archaean to earlyProterozoic metamorphic complex. In the Dabie area, the ultra-high-pressure eclogite,high-pressure eclogite and epidote-blueschist units are nearly parallel to each other and stretchintermittently from north to south. (2) The P-T conditions of the high-pressure eclogites and ul-tra-high pressure eclogites have been estimated. The former are formed at 450-550℃ and1.4-1.6 GPa; while the latter at 650-870℃ and >2.7-2.9 GPa in the Dabie area and at820-1000℃ and >2.8-3.1 GPa in the Sulu area. The metamorphic temperatures of the eclogitesincrease progressively from west to east. (3) The ultra-high pressure eclogites were subjected to 5stages of metamorphism: pre-eclogite epidote amphibolite facies, peak coesite eclogite facies,post-eclogite amphibolite facies, epidote-blueschist facies or epidote amphibolite facies andgreenschist facies. The general features of the PTt path of the ultra-high pressure eclogite are:clockwise pattern, progressive metamorphism being a process of slow increasing temperature andrapid increasing pressure, and the retrogressive section with nearly isothermal decompression atthe early stage, isobaric cooling at the middle stage and nearly isothermal decompression at thelate stage. (4) At least two stages of high-pressure metamorphism occurred in the orogenic belt:the high-pressure eclogite and ultra-high pressure eclogite were formed by the subduction of theoceanic crust northward beneath the North China plate or the Dabie block during theCaledonian; while the epidote-blueschist belt came into being by subdution and collision be-tween the two continental plates during the Indosinian. (5) Due to the continuous sequentialsubduction of the cold plate, the ultra high-presssure metamorphic rocks were uplifted to thecrust by the underplating processes. They can be preserved just because of the "frozen effect" re-sulting from the continuous subduction of the cold plate. (6) The carbonates, such as magnesite,breunnerite, aragonite and dolomite, and the H_2O-bearing minerals, such as phengite, epidoteand zoisite, were stable during the high-pressure and/or ultra-high pressure metamorphism. 相似文献
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煤矿开采已形成系列和成套的先进机械设备,煤矿与化工矿山既有各自的特殊性也有一定的共性,化工矿山引进应用一些采煤机械设备可以优化和创新开采技术方案,如:机械切割开采技术——连续采煤机与掘进机,工作面支护技术——液压支柱与液压支架,胶带输送技术——大倾角胶带机。通过加强沟通交流,加强试验研究,积极探索,可以促进非煤矿山开采技术的优化和创新。 相似文献
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《International Geology Review》2012,54(1):3-10
At the base of the sedimentary section of the Timan-Pechora basin are Late Precambrian rifts, which are filled by unmetamorphosed sedimentary rocks 10 km and more than 10 km thick. The upper parts of these rift deposits have potential for gas. Structurally the Phanerozoic sedimen tary fill of the basin is mildly deformed in the west and central parts into several broad depressions and more narrow intervening highs. The eastern part is strongly deformed by overthrusts that were emplaced in the Late Paleozoic in connection with development of the Ural fold belt. Eight oil-gas plays are recognized in the basin: 1—Ordovician-Lower Devonian, 2—Middle Devonian-lower Frasnian, 3—upper Frasnian-Tournaisian, 4—Lower Carboniferous, 5—upper Visean-Lower Permian, 6—Lower Permian, 7—Upper Permian, and 8—Triassic. The promising oil-gas basin is of great interest for global stratigraphy and tectonics as well as for petroleum exploration. 相似文献
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新疆阿尔泰萨热阔布-铁木尔特地区两类矿化及成因 总被引：2，自引：0，他引：2
新疆阿尔泰南缘萨热阔布-铁木尔特一带的矿床均赋存于下泥盆统康布铁堡组的变质岩系中。早泥盆世的海相火山形成了Zn--Pb ( Cu) 矿化,晚泥盆世--早石炭世的碰撞造山相应形成了Cu--Au 石英脉矿化; 前者以铁木尔特VMS 型Zn--Pb ( Cu) 矿床为代表,后者以造山型萨热阔布金矿为代表,与造山有关的脉状矿化还叠加在铁木尔特等VMS 矿床中。通过对比两类矿化的稳定同位素特征,结合矿化的变形变质和流体包裹体特征,研究了成矿物质、成矿流体来源和矿床成因。萨热阔布金矿主成矿阶段硫化物石英脉和铁木尔特Zn--Pb ( Cu) 矿床中晚期发育的含黄铜矿石英脉中均富含碳质 ( CO2--CH4--N2 ) 流体包裹体,可能与碰撞造山的热液流体作用有关。铁木尔特Zn--Pb ( Cu) 矿床中代表VMS 期的浸染状矿石中硫化物δ34S 为－26. 46 × 10-3 ～ －19. 72 × 10 -3,硫主要来源于海水硫酸盐的无机还原和细菌还原作用; 而代表后期叠加改造的脉状矿化硫化物值与萨热阔布金矿床硫化物石英脉中δ34S 值接近,硫主要来源于造山过程中的深源流体。萨热阔布金矿床硫化物石英脉和铁木尔特Zn-- Pb ( Cu) 矿床晚期含黄铜矿石英脉的δDH2O 值和δ18OH2O 值,均反映了碰撞造山期热液与岩浆活动和变质作用有关。萨热阔布金矿硫化物石英脉中碳质流体包裹体CO2 体系中δ13 C 为－ 21. 15 × 10-3 ～ －7. 51 × 10 -3,CH4 体系的δ13C 为－34. 11 × 10 -3 ～ －28. 38 × 10-3 ; 铁木尔特Zn--Pb ( Cu) 矿床含黄铜矿石英脉中碳质包裹体测得的δ13C 为－8. 02 × 10 -3 ～ －6. 99 × 10 -3,δ13 C 特征与海相火山沉积无关,具岩浆源或深部源的特点。 相似文献
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邓阜仙钨矿成矿构造特征及深部成矿预测 总被引：8，自引：1，他引：8
孙振家 《大地构造与成矿学》1990,14(2):139-150
邓阜仙钨矿位于湘赣地洼系衡山地穹内地洼型花岗岩中。矿床构造为典型的脉状构造。单脉,脉列,脉群在空间上严格按一定的几何关系分布。矿脉雁列脉,侧羽脉的三维形态特征,反映它们剪切形成的机制。经我们对该区航片、卫片分析,发现NNW向构造带与环形影像带,由此而确立了NNW向矿带的新认识。结合矿化与蚀变强度的空间分布,以及发现客观存在的构造等距性、对称性、梯级面,预测出新矿床(体)的空间位置,并得到物探与工程的验证。 相似文献