排序方式： 共有37条查询结果，搜索用时 171 毫秒
1.
柴河铅锌矿成矿物质来源初步探讨 总被引：1，自引：0，他引：1
柴河铅矿成矿物质来源是多源的。矿质来源主要来自下伏的老基底岩石,部分来自矿床围岩——高于庄组条带状白云岩。基底岩石中的含矿热卤水,沿NF1这条切割震旦系地层到达基底岩石的断裂上升,运移到震旦系高于庄组成矿有利围岩（条带状白云岩）中并在有利部位富集成矿。 相似文献
2.
地球物理反问题存在多解性和不稳定性,正则化是得到稳定解的重要手段之一,正则化方法中稳定因子的设计与正则化因子的选择是两项重要研究内容。稳定因子的主要功能是对模型的解空间进行限制,以减少多解性,求得稳定解;为更好的定位地下目标体,研究工作采用了最小支持稳定因子,并给出了统一表达形式。正则化因子在模型误差与数据误差之间起到平衡作用,研究工作在＂L曲线法＂自动选取正则化因子的基础上,提出一种修正的计算正则化因子算法。以2.5维直流电阻率为例,运用非线性共轭梯度法,进行了试算研究,结果表明了修正的＂L曲线法＂算法快速、稳定,最小支持稳定因子具有较好的聚焦特性,有利于实现陡变边界反演。 相似文献
3.
五龙金矿是辽东地区大型岩浆热液型金矿床,163矿脉是矿区内目前发现的最大含矿构造。为进一步探测深部找矿潜力,近几年矿山对163矿脉进行了大量的探采工程,其中在-762 m坑道实施了600 m钻孔。本文在详细编录该钻孔的基础上,对全孔样品进行成矿元素测试工作,利用SPSS软件对所得测试数据进行元素相关性、聚类、因子分析。相关性分析显示,具有显著正相关的元素主要为Bi、W、Cu、Ag、Au和As、Sb、Sn、Zn两组;Mo元素与Sn、Ag、Cu、Bi、W、Sb地素具有显著正相关性,而Pb元素与Cu、Mo、Au、W元素呈显著负相关性,Hg元素与其它元素相关性不明显。聚类分析结果表明,R型聚类在类的距离为5的水平上,这些元素明显可分为3组：Hg、Cu、Pb、Zn、Sn、Mo、As、W;Ag、Au、Sb、Bi。因子分析结果表明,提取3个因子可以反映出12个元素变量64.42%的地球化学信息,F1的主要载荷因子组成为Sn、Ag、As、Zn、Sb, F2的主要载荷因子组成为Au、W、Bi、-Pb, F3的主要载荷因子组成为Hg。根据成矿元素随深度变化特征,结合前人构造叠加晕研究成果,推测该钻孔深部还... 相似文献
4.
辽宁五龙金矿是辽东地区大型岩浆热液型矿床之一,成矿作用主要与中生代火成岩有关,为了进一步理清五龙地区中生代火成岩成因,本文对五龙金矿区大量花岗斑岩脉、闪长岩脉、三股流岩体和其中的各类脉岩进行了单颗粒锆石LA-ICPMS U-Pb测年和岩石主、微量元素地球化学研究。结果表明,五龙地区岩浆岩形成时代主要有晚侏罗世和早白垩世,矿区内近南北向展布的花岗斑岩脉形成于晚侏罗世（154.3±0.9~155.6±1.1 Ma）,指示矿区在晚侏罗世受到区域最大主应力方向为近南北向;三股流岩体成岩最新年龄（116.8±0.8~117.3±0.7 Ma）基本位于前人报道的年龄范围（111~129 Ma）;地球化学数据表明各类岩浆岩属于高钾钙碱性—钾玄岩系列,具有相同源区特征,形成于活动大陆边缘俯冲伸展环境下的弧岩浆,并且具有壳幔混合及进一步演化特征;结合不同深度标高成矿元素丰度特征,指示闪长岩与成矿作用密切相关,并且越往深部成矿潜力越大,对该地区找矿预测具有重要指导意义。 相似文献
5.
Gang Yu Jiangfeng Chen Chunji Xue Yuchuan Chen Fukun Chen Xiaoyue Du 《Ore Geology Reviews》2009,35(3-4):367-382
The Qingchengzi orefield in northeastern China, is a concentration of several Pb–Zn, Ag, and Au ore deposits. A combination of geochronological and Pb, Sr isotopic investigations was conducted. Zircon SHRIMP U–Pb ages of 225.3 ± 1.8 Ma and 184.5 ± 1.6 Ma were obtained for the Xinling and Yaojiagou granites, respectively. By step-dissolution Rb–Sr dating, ages of 221 ± 12 Ma and 138.7 ± 4.1 Ma were obtained for the sphalerite of the Zhenzigou Zn–Pb deposit and pyrargyrite of the Ag ore in the Gaojiabaozi Ag deposit, respectively. Pb isotopic ratios of the Ag ore at Gaojiabaozi (206Pb/204Pb = 18.38 to 18.53) are higher than those of the Pb–Zn ores (206Pb/204Pb = 17.66 to 17.96; Chen et al. [Chen, J.F., Yu, G., Xue, C.J., Qian, H., He, J.F., Xing, Z., Zhang, X., 2005. Pb isotope geochemistry of lead, zinc, gold and silver deposit clustered region, Liaodong rift zone, northeastern China. Science in China Series D 48, 467–476.]). Triassic granites show low Pb isotopic ratios (206Pb/204Pb = 17.12 to 17.41, 207Pb/204Pb = 15.47 to 15.54, 208Pb/204Pb = 37.51 to 37.89) and metamorphic rocks of the Liaohe Group have high ratios (206Pb/204Pb = 18.20 to 24.28 and 18.32 to 20.06, 207Pb/204Pb = 15.69 to 16.44 and 15.66 to 15.98, 208Pb/204Pb = 37.29 to 38.61 and 38.69 to 40.00 for the marble of the Dashiqiao Formation and schist of the Gaixian Formation, respectively).Magmatic activities at Qingchengzi and in adjacent regions took place in three stages, and each contained several magmatic pulses: ca. 220 to 225 Ma and 211 to 216 Ma in the Triassic; 179 to 185 Ma, 163 to 168 Ma, 155 Ma and 149 Ma in the Jurassic, as well as ca. 140 to 130 Ma in the Early Cretaceous. The Triassic magmatism was part of the Triassic magmatic belt along the northern margin of the North China Craton produced in a post-collisional extensional setting, and granites in it formed by crustal melting induced by mantle magma. The Jurassic and Early Cretaceous magmatism was related to the lithospheric delamination in eastern China. The Triassic is the most important metallogenic stage at Qingchengzi. The Pb–Zn deposits, the Pb–Zn–Ag ore at Gaojiabaozi, and the gold deposits were all formed in this stage. They are temporally and spatially associated with the Triassic magmatic activity. Mineralization is very weak in the Jurassic. Ag ore at Gaojiabaozi was formed in the Early Cretaceous, which is suggested by the young Rb–Sr isochron age, field relations, and significantly different Pb isotopic ratios between the Pb–Zn–Ag and Ag ores. Pb isotopic compositions of the Pb–Zn ores suggest binary mixing for the source of the deposits. The magmatic end-member is the Triassic granites and the other metamorphic rocks of the Liaohe Group. Slightly different proportions of the two end-members, or an involvement of materials from hidden Cretaceous granites with slightly different Pb isotopic ratios, is postulated to interpret the difference of Pb isotopic compositions between the Pb–Zn–(Ag) and Ag ores. Sr isotopic ratios support this conclusion. At the western part of the Qingchengzi orefield, hydrothermal fluid driven by the heat provided by the now exposed Triassic granites deposited ore-forming materials in the low and middle horizons of the marbles of the Dashiqiao Formation near the intrusions to form mesothermal Zn–Pb deposits. In the eastern part, hydrothermal fluids associated with deep, hidden Triassic intrusions moved upward along a regional fault over a long distance and then deposited the ore-forming materials to form epithermal Au and Pb–Zn–Ag ores. Young magmatic activities are all represented by dykes across the entire orefield, suggesting that the corresponding main intrusion bodies are situated in the deep part of the crust. Among these, only intrusions with age of ca. 140 Ma might have released sufficient amounts of fluid to be responsible for the formation of the Ag ore at Gaojiabaozi.Our age results support previous conclusions that sphalerite can provide a reliable Rb–Sr age as long as the fluid inclusion phase is effectively separated from the “sulfide” phase. Our work suggests that the separation can be achieved by a step-resolution technique. Moreover, we suggest that pyrargyrite is a promising mineral for Rb–Sr isochron dating. 相似文献
6.
辽东王家堡子地区出露大量古元古代花岗质岩石,前人将其统称为花岗质混杂岩。通过详细的野外地质调查和室内综合研究,将该套花岗质混杂岩解体为条痕状黑云母二长花岗岩和片麻状黑云母二长花岗岩两类。岩石地球化学分析结果显示二者具有一致的地球化学特征。均显示高SiO_2、富K_2O、贫Al_2O_3的特征,K_2O/Na_2O=0.64～2.14,TiO_2含量为0.16%～0.3%,MnO、MgO、CaO和P_2O_5的含量较低,铝指数A/CNK集中分布在1.06～1.1之间,A/NK在1.50～1.62之间,均属于过铝质高钾钙碱性系列;微量元素显示强烈亏损Nb、Ti、Ta等高场强元素,富集Rb、U、K等大离子亲石元素,具有明显的负Eu异常,具有A型花岗岩的特征。条痕状黑云母二长花岗岩大部分锆石为具有清晰振荡环带的岩浆锆石,LA-ICP-MS锆石U-Pb年龄为2188±13Ma,代表该岩石的岩浆结晶年龄。片麻状黑云母二长花岗岩大部分锆石具有明显的变质增生边,部分核部锆石具有清晰的振荡环带,LA-ICP-MS锆石U-Pb测年获得核部年龄为2214±16Ma,代表该岩石的岩浆结晶年龄;增生边年龄为1905±13Ma,应代表该岩石的变质年龄。条痕状黑云母二长花岗岩和片麻状黑云母二长花岗岩的Hf同位素模式年龄分别为2387～2584Ma和2474～2641Ma,平均地壳模式年龄分别为2495～2808Ma和2633～2868Ma,大于岩石形成年龄,暗示研究区古元古代花岗岩源区主要为太古宙基底,混有少量古元古代新生地壳。结合前人报道的埃达克质花岗闪长岩的形成环境,认为胶-辽-吉古元古代造山/活动带早期经历了2.2～2.15Ga的拉伸裂解过程和2.0Ga左右俯冲挤压的构造演化过程。 相似文献
7.
利用GPS手持机对地质观察点进行坐标数据的采集,通过GPS手持机应用软件（GISOffice、MapSource）将所采集的原始数据传输保存到电脑中,使用Microsoft Office办公软件（Access、Excel）对数据进行整理、应用,或存贮、共享应用于其他地质资料整理. 相似文献
8.
矿集区找矿预测研究——以辽东青城子铅锌-金-银矿集区为例 总被引：7，自引：4，他引：3
矿集区找矿预测有着不同于典型矿床和区域性成矿预测的规律和特点,是在厘定区内主要类型矿床的成因类型基础上,以"三位一体"(即成矿地质作用与成矿地质体、成矿构造与成矿结构面、成矿作用特征标志)和成矿系统为主要内容开展工作。文章以辽宁青城子铅锌-金-银矿集区为例,系统总结了矿集区的矿床类型、岩浆-成矿系统、"三位一体"找矿预测要素等关键科学问题。青城子矿集区是中国重要的铅锌-金-银矿集区,由于多年的开采,青城子等矿山濒临危机,如何取得该地区找矿突破,是一个亟待解决的问题。对前人研究成果分析表明,该矿集区内铅锌矿床和金、银矿床的成因类型可能均属于岩浆热液型,而非元古代喷流沉积型,矿床的"层控"现象实为特定岩性界面控制的有利成矿结构面;成矿作用主要与印支期花岗斑岩有关,铅锌矿和金、银矿可能是同一岩浆系统演化的产物。在未来的找矿预测中,应重点开展以下5方面工作:(1)查明矿床的具体成矿地质体;(2)进一步提炼成矿期构造控矿规律和成矿结构面样式;(3)凝练有效的成矿作用特征标志,重点是与成矿有关的远程蚀变标志;(4)构建和完善矿集区中生代岩浆-成矿系统,并注意新矿种、新矿床类型的寻找;(5)探索研究矿集区的自然边界,扩大找矿范围和深度。 相似文献
9.
10.
大量研究表明辽宁青城子地区主要成矿作用与印支期岩浆活动有密切关系,为了进一步研究印支期岩浆活动与成矿关系,文章在详细野外工作的基础上,对印支期侵入岩体进行了岩石地球化学测试分析。结果表明,青城子地区印支期花岗岩的w(SiO2)介于61.67%～77.69%,w(K2O)介于3.96%～6.67%,w(Na2O)为0.04%～4.42%,里特曼指数为0.57～5.19,多数小于3.3,主要为高钾钙碱性和钾玄岩系列;在以w(SiO2)为横坐标、其他氧化物为纵坐标的哈克图解中,除了w(Na2O)、w(K2O)与w(SiO2)的线性关系不明显外,其他氧化物均与w(SiO2)呈线性关系,说明它们具有明显的岩浆演化关系;微量元素均富集大离子亲石元素,亏损高场强元素,原始地幔标准化配分曲线呈右倾模式,稀土元素球粒陨石标准化配分模式呈轻稀土元素富集、重稀土元素亏损的右倾模式;构造判别图指示了青城子地区印支期岩浆活动产于同碰撞大地... 相似文献