内蒙古东伙房金矿床矿物包裹体研究和矿床成因     

石准立  谢广东 《现代地质》1998,12(4):477-484

摘　 要　 着重研究了东伙房金矿床矿物包裹体的空间分布, 并将其用于解释矿床成因。 研究 了成矿压力场、 温度场和热液沸腾与矿质沉淀的关系, 利用矿物包裹体气相和液相成分测定 结果讨论了金的搬运形式。 论述了碱性潜火山岩正长斑岩体与成矿的关系, 指出矿床形成于 印支期地幔热柱引发的张性成矿动力学背景之下, 矿床属于和碱性岩有关的中浅成高中温热 液矿床。  相似文献   

岩浆 热液过渡型矿床的若干特征   总被引：10，自引：0，他引：10  

林新多 《现代地质》1998,12(4):485-492

摘　 要　 在内生成矿作用中成矿流体有 3 种:岩浆、 热液和岩浆 热液过渡性流体。 从地质研 究、 矿物包裹体、 成矿实验 3 个方面简介了岩浆 热液过渡型矿床研究的进展。 指出岩浆 热 液过渡性流体有 2种形成方式:一是在岩浆结晶过程中挥发分不断集中而形成, 另一是由熔 离作用所形成。 并从矿体与岩浆岩的关系、 矿体与围岩的关系、 矿石的结构构造、 围岩蚀变、 分带现象、 矿物包裹体 6 个方面总结了岩浆 热液过渡型矿床的特征。  相似文献   

亦论韧性剪切变形与金的成矿作用——与邵世才《试论韧性剪切变形与金的成矿》一文的讨论   总被引：2，自引：0，他引：2  

陈柏林  李中坚  董法先 《地质与资源》1998,7(3):228-232

剪切带型金矿是一种重要的金矿类型.韧性-超韧性深层次剪切变形是促使Au元素活化分异、形成动力变质含金热液的过程,中浅层次的韧脆性、脆性剪切变形区是Au元素聚集成矿部位.韧脆性剪切带的不同变形层次及其构造岩类型决定了剪切带型金矿床的矿化类型.剪切带型金矿床往往具有成矿时代滞后、空间规模差异、物源指示差异、韧性变形强度与Au元素含量反相关等异常特征.长期演化的造山带附近及边缘是寻找大型剪切带型金矿床的有利地区.  相似文献   

华南中、低温成矿带元素组合和流体性质的区域分布规律   总被引：9，自引：1，他引：8  

马东升 《矿床地质》1999,18(4):6

华南中、低温成矿带主要由江南古陆的“江南型”金＿锑矿带、湘黔汞矿带、西南卡林型金矿区和湘中锑矿带组成。其成矿时代有自东向西从燕山早期到中、晚期有变新的趋势; 矿种分布和成矿元素组合表现出对元古宇基底的继承性; 成矿流体的温度和盐度在大区域内从东到西和自南向北分别呈现降低和增高的趋势, 并且在古陆西、北侧的盆地中有盆地卤水混合的现象。研究表明, 华南中、低温成矿带的时空分布和成矿元素组合演化与华南燕山期花岗岩强烈活动的华南钨（ 锡） 成矿域有密切的联系。这些大型矿集区都集中形成于燕山期, 并与川东南油气田一起, 共同构成了一个自南东向北西的高—中—低温热液矿床和油气矿藏的区域性矿化巨型分带。从而表现出大华南地区（ 东南、中南和西南） 在燕山期曾经历过统一热场作用下的大范围流体运动和大规模成矿作用  相似文献   

粤东地区官田含铜碲黄铁矿矿床的火山热液成因     

夏学惠 《地质论评》1999,45(7):823-828

本文从矿床成矿地质背景角度,讨论了粤东地区官田矿床地质地球化学特征及其与火山热液作用的成因联系。阐述了矿区矿化元素分带的原因。研究表明,火山热液是矿床形成的主导因素,它与复式杂岩体演化晚期气液相遇运移至断裂破碎带形成含铜碲黄铁矿矿床。在含矿热液运移过程中有大气降水加入,发生了强烈的水岩交换,产生大面积的黄铁绢英岩化。随着温度的降低,热液运移至金鸡群萃取了碎屑岩内的Pb、Zn元素,形成了湖洋坑铅锌矿床。  相似文献   

Comparison of Internal Structures of Marine Manganese Deposits of Hydrogenetic, Diagenetic and Hydrothermal Origins     

Yumi HAT TA  Makoto WATANABE  Kenichi HOSHINO  Akira USUI 《Resource Geology》1999,49(1):49-54

Abstract: Detailed microscopic observation, combined with X-ray diffraction and EPMA analyses of samples from marine manganese deposits of three different origins, suggests that characteristic internal structures are inherent in each manganse mineral; vernadite (δ–MnO₂), buserite (10Å–manganate) and todorokite (10Å–manganate).  相似文献   

Stability analysis of the heave motion of marine cable-body systems     

S. Huang   《Ocean Engineering》1999,26(6):225

The dynamic stability of the heave motion of marine cable-body systems operating in alternating taut–slack conditions is considered, based upon a single-degree-of-freedom model. In this model the fluid damping is linearised and the cable is replaced by a spring of bi-linear stiffness. The period-one Poincare map is derived, and its stability is analysed by examining its Jacobian matrix. Numerical simulations are also carried out to show the transition from a periodic response to a chaotic one through period doubling.  相似文献   

Application of SAR Imagery in Submarine Topography Surveys     

张宁川  梁开龙  桂力民 《海洋通报(英文版)》2004,6(1)

An important research area in oceanographic surveying and mapping is to obtain submarine topography by remote sensing technique, especially by SAR imagery. In this article, problems related to SAR imagery are analyzed to provide references for the further research.  相似文献   

REE and Sr-Nd isotope characteristics of hydrothermal chimney at Jade area in the Okinawa Trough     

LIU Yanguang  MENG Xianwei  FU Yunxia 《海洋学报(英文版)》2004,23(2):287-296

Hydrothermal chimney is a product of hydrothermal activity on the seabed. Chimney samples dredged from Jade hydrothermal area in Izena depression of the Okinawa Trough, are characterized by relatively enriched light rare earth elements (LREE) and strongly positive Eu anomalies. ^87Sr/^86Sr and ^143Nd/^144Nd of these samples are exactly between those of seawater and of acidic pumice, averaged at 0.708928 and 0.512292, respectively. These characteristics imply that the main source of hydrothermal sulfide at Jade area is possibly the undersurface acidic rocks. The mineralizing mechanism can be summarized as follows: Large amount of mineralized material would be leached out and LREE-enriched hydrothermal solution would be subsequently produced as a result of thermo-chemical exchange reaction between acidic volcanic rocks and heated seawater that penetrated in advance from upper water mass. The spurting out from the seabed and quickly crystallizing in the seawater of hydrothermal solution are responsible for the formation of Cu-Zn sulfide and barite-amorphous SiO2 minerals that are characterized by enriched LREE and positively strong Eu anomalies.  相似文献   

Effect of seasonal freeze–thaw process on spatial and temporal distribution of soil water and its infiltration to recharge groundwater     

Zhongle Cheng  Fugang Wang  Jingwei Sun  Lujiao Ding  Yaohui Wang  He Wang 《水文研究》2024,38(3):e15110

Clarifying the distribution and dynamics of soil moisture during the freeze–thaw process is crucial for surface ecology and is an objective requirement to investigate the mechanism of changes during the groundwater recharge process in a freeze–thaw zone. Based on the monitoring data of soil moisture and temperature in the Changbai Mountain area, the freeze–thaw process is classified into four periods. This study investigates the hydrothermal migration processes during different periods. The simultaneous heat and water model is used to simulate and analyse the infiltration of soil moisture into groundwater under five precipitation insurance rates. The results are as follows: (1) The smaller the soil depth, the stronger is the correlation between soil temperature and air temperature during the freeze–thaw process. (2) The redistribution of soil moisture before and after freeze–thaw is significantly affected by the soil texture, and soil permeability affects the recharge of soil moisture from the upper region to the lower region during the thawing period. (3) Groundwater receives vertical infiltration recharge mainly during non-freezing and is supplied by freezing and snowmelt recharge during the stable thawing period. The percentage of soil water infiltration during the stable thawing period in the total annual infiltration increases gradually with the precipitation insurance rate.  相似文献