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1.
海底黑烟囱的识别研究及其科学意义 总被引：22，自引：4，他引：18
现代海底黑烟囱广泛出现于大洋中脊、弧后盆地、浅海及大陆裂谷等环境,形成巨大规模的块状硫化物,并且在黑烟囱周围发现了化学自养细菌。海底硫化物黑烟囱具有明显的柱状-锥状构造形态,常保留通道构造,矿物同心圈状分带明显。黑烟囱的形成涉及热液流体与海水相互作用,外壁快速沉淀及通道内部硫化物结晶等过程。深部岩浆热源、热液沿裂隙集中流动和持续喷发,有利于形成大规模黑烟囱构造。海底硫化物丘体的钻探及其与地史时期块状硫化物的对比研究表明,它们具有相似的内部构造和矿床分带特征。黑烟囱的生长、垮塌以及丘体内部角砾化、交代、重结晶作用,有助于大规模矿床的形成。最后,在块状硫化物中寻找黑烟囱残片的研究,对于探讨成矿过程与早期生命活动具有重要意义。 相似文献
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3.
海底硫化物黑烟囱典型结构构造及其成因意义 总被引：4，自引：0，他引：4
在已发现的现代海底黑烟囱中基本都发育分带性构造、通道构造、胶状构造、多孔和填充构造、交代构造、枝状构造等,这些构造为硫化物烟囱的典型构造,它们记录了硫化物烟囱的形成过程和每个阶段的特征,是鉴别硫化物烟囱构造的重要特征。不同类型烟囱的形成除了与其围岩相关外,也与烟囱演化的成熟度相关。弥散式喷射作用(diffuser)是与烟囱构造相似的常在丘体中发育的另一重要构造,与烟囱构造不同的是弥散式喷射缺乏象烟囱那样的轴向中央通道,热液与海水的混合有严格的范围。烟囱与弥散式喷射作用是丘体上部形成的主要机制。在现代陆上保存的地史时期的块状硫化物矿床中,陆续找到了遗留下来的烟囱构造或烟囱残片(如乌拉尔、皮尔巴拉、爱尔兰、高板河等),为块状硫化物矿床的黑烟囱形成机制提供了直接的证据。 相似文献
4.
安徽铜陵矿集区块状硫化物矿床成因模型与成矿流体动力学迁移 总被引：12，自引：1，他引：12
根据地质和同位素地球化学特征，建立了铜陵地区赋存于石炭系地层底部的块状硫化物矿床的成因模型；该类型矿床的形成主要与石炭纪海底热水活动有关，属喷流-沉积型(SEDEX)块状硫化物矿床；下伏古生代地层是重要的成矿金属源区，海水硫酸盐是硫化物成矿的主要硫源。成矿热流体循环的动力学数值模拟揭示。该类型矿床底盘岩石中的流体活动和热影响范围主要局限在主排泄通道两侧较小的区域内；温度场和流场决定以沉积岩为容矿岩石的喷流．沉积型块状硫化物矿床底盘岩石中的蚀变和矿化强度不如以火山岩为容矿岩石的块状硫化物矿床。伴随强大深部热流的张性同生断裂是控制喷流一沉积型块状硫化物矿床形成与分布的关键因素。海西期扬子板块北缘的张性构造体制为该时期喷流一沉积型块状硫化物矿床的形成提供了有利的地球动力学环境。 相似文献
5.
通过对闽西南地区石炭纪—早二叠世主要块状硫化物矿床的区域成矿背景、贮矿层位特征以及矿石矿物成分、结构构造,硫同位素地球化学特征、成矿温度等分析研究,指出该地区石炭纪—早二叠世块状硫化物矿床的形成多与海底火山活动有关,贮矿层中伴有典型的喷流沉积岩—硅质岩,并提出闽西南地区块状硫化物矿床存在海底喷流-沉积成矿作用的新认识。 相似文献
6.
论华南喷流－沉积块状硫化物矿床 总被引：27，自引：1，他引：27
现代海底喷流－沉积硫化物矿床的发现极大地推动了海底热液成矿理论的发展，也大大地提高了对古代海底喷流块状硫化物矿床的研究水平。本文指出喷流－沉积是重要的成矿作用，提出喷流－沉积矿床是华南Ｃｕ、Ｐｂ、Ｚｎ、Ｓｎ、Ａｇ、Ａｕ等矿产资源的重要来源，形成了一批超大型矿床，并将华南许多曾被认为属夕卡岩型的矿床重新确认为喷流－沉积矿床。文章还论述了华南喷流－沉积块状硫化物矿床的特征、分类、时空分布及其成矿特点等问题，提出断裂拗陷带型喷流－沉积块状硫化物矿床是华南具有特色的类型，而陆相断陷盆地中喷流－沉积矿床值得进一步深入研究 相似文献
7.
塞浦路斯特罗多斯晚白垩世蛇绿岩体中的块状硫化物矿床具有现代海洋扩张中央著名的硫化物矿床，沿特罗多斯杂岩体北部边缘分布的几个硫化物矿床与古海底扩张有关的构造地堑有空间上的关系，尽管矿床的构造背景类以于超俯冲带而不是洋中脊，塞浦路斯块状硫化物矿床的总成分和矿化类型相当于现代洋中脊正在形成的“黑烟卤”矿床。此矿床以含大量的黄铁矿为特征，此外，还有黄铜矿，少量的闪锌矿和白铁矿，磁黄铁矿，该类矿床的黄金产理 相似文献
8.
现代海底热液活动与块状硫化物矿床成因研究进展 总被引：8，自引：0，他引：8
现代海底热液活动的发现及对其分布特征和成矿机理的研究是近年来海洋地质学和矿床地质学的一大进展。对现代海底金属硫化物成矿作用的研究大大推动和促进了对古代块状硫化物矿床成因的认识。有关研究成果综合分析表明：(1)深部热液对流循环系统是块状硫化物成矿的核心，对流循环模式有简单的热液对流模式和双扩散对流模式。(2)块状硫化物矿床集中分布在大洋中张裂性活动板块边界，与大地构造活动紧密联系。(3)成矿流体与成矿物质均有多源性，在强调海水循环淋滤的同时，通过应用新的方法技术，岩浆来源物质(流体及成矿金属等)对一些块状硫化物矿床成矿的直接贡献得到初步确认。(4)在高温热液活动区及金属硫化物沉积中发现大量生命活动和生物群体，意义重大。 相似文献
9.
李文渊 《西安地质学院学报》2010,(1):15-23
从现代块状硫化物矿床成矿特征对比角度,总结分析了世界现代海底喷流的块状硫化物成矿堆积,综述了现代海底块状硫化物成矿主要形成于洋壳和岛弧环境的实际观察结果,突出强调了洋壳环境和岛弧或陆壳环境两种成矿环境对成矿类型分类的意义。对上地幔部分熔融岩浆来源与地壳物质可能带人、火山喷发岩浆系列的演化和对热液成矿作用的控制进行了讨论,对比分析了岩浆流体对成矿的重要贡献和控制作用,以及成矿热液循环体系形成的条件和模式。 相似文献
10.
对铜陵地区石炭纪喷流 -沉积型 (Sedex)块状硫化物矿床成矿过程中流体运移的数值模拟 ,揭示该类型矿床底盘岩石中的流体活动和热影响范围主要局限在主排泄通道两侧较小的区域内 ;流体运移行为主要表现为海水下渗淋滤底盘岩石 ,最后汇入主排泄通道 ,与沿断裂上升热流体一道喷出海底。温度场和流场决定喷流 -沉积型块状硫化物矿床底盘岩石中的蚀变和矿化强度较弱 ,这是 Sedex型矿床底盘岩石蚀变和矿化强度不如以火山岩为容矿岩石块状硫化物矿床(VHMS型 )的原因。尽管温度场和流场的影响范围较小 ,但在铜陵地区 ,下渗海水从底盘岩石中淋滤出… 相似文献
11.
Mineralization of a Proterozoic Sulfide Black Smoker Chimney and Thermophilous Microorganisms in Eastern Hebei, China 总被引：1，自引：1，他引：0
A sulfide black smoker chimney exists in the Gaobanhe seabed exhalation massive sulfide deposit in the Xingiong-Kuancheng secondary fault basin of the Proterozoic Yaniiao rift trough in Hebei Province, taking the shape of mounds, individually about 2-3 cm high. Abundant fossils of thermophilous bacteria and algae in perfect preservation are found in the ore surrounding the black smoker chimney. Scanning electron microscopy （SEM） and molecular biomarker studies on the microorganismai ore fabric show that the microorganism in the sulfide ore is in fact a sedimentary product of probiotic bacteria and algae. In the special food chain based on black smoker chimney at ancient seabed- thermophilous bacteria, the thermophilous bacteria and algae reproduce in large quantity. Intermittently erupting of fluid from the chimney creats conditions for formation of sulfide deposit. In the process of exhalation action of hot fluid, thermophilous bacteria and algae grow and reproduce around the sulfide black smoker chimney, absorbing mineralizing substances brought by the fluid. Massive sulfide deposits are formed in this process of absorption of seabed black smoker chimney exhalation-mineralizing fluid pulsation-thermophilous microorganism. 相似文献
12.
Black smoker chimneys and biological vent communities have been identified at many sites on the deep seafloor, particularly along oceanic spreading centers. We report the largest and oldest known, microbe-rich sub-meter-sized black smoker chimneys and mounds from a 1.43 billion-year old sulfide deposit in a continental graben in northern China. These chimneys are especially well preserved, with characteristic morphology, internal textures and internal cylindrical mineralogical zonation. Four main types of chimneys are distinguished on textural and mineralogical criteria, exhibiting either Zn–Fe-sulfide or Pb–Zn–Fe-sulfide internal cylindrical mineralogical zones. The chimneys mark vent sites in submarine grabens indicating focused flow-venting processes. The fossil chimneys have mineralogical and geological evolutionary features similar to their counterparts on the modern seafloor and other submarine hydrothermal vents. Black smoker vent fluids and seafloor tectonism played important roles for formation of the massive sulfide deposits in the Mesoproterozoic.We also report the first known, remarkably diverse assemblage of fossil microbialites from around and inside Precambrian vent chimneys, demonstrating that Proterozoic life flourished around submarine hot vents and deep within the chimney vent passages. Filamentous, spherical, rod, and coccus-shaped fossil microbes are preserved preferentially on sulfide precipitates. Based on the depth and setting of the fossil biota, the organisms that produced the microbialites were likely sulfate-reducing chemosynthetic and thermophyllic microbes. Textural and mineralogical evidence shows that biomineralization processes enhanced chimney growth and sulfide precipitation.Close association of microorganisms with sulfide chimneys in modern deep-sea hydrothermal vents and younger ophiolites has sparked speculation about whether life may have originated at similar vents. However, little is known about fossil equivalents of vent microfossils and black smoker chimneys from Earth's early evolution. The fossilized microorganisms from the Gaobanhe black smoker chimney sulfide deposits include thread-like filaments with branching and twisted forms and preserved organic carbon, representing fossilized remnants of microbial mats metabolized at high temperatures characteristic of venting fluids. The preservation of fossil microorganisms provides evidence that microbial populations were closely associated with black smoker chimneys in Earth's early history. The microbial population clearly constitutes the site for mediating mineral formation. These ancient microbial fossils lead to a much better understanding of early life on the deep seafloor. The discovery of the Mesoproterozoic microfossils within black-smoker hydrothermal chimneys indicates that hydrothermal activity around sea-floor vents supported dense microbial communities, and supports speculation that vent sites may have hosted the origin of life. 相似文献
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The bedded clastic ore widespread on the slopes and flanks of the deeply eroded sulfide mound at the Saf’yanovka volcanic-hosted
copper massive sulfide deposit consists of products of destruction of the Paleozoic black smoker along with diverse newly
formed sulfides. The size of ore clasts gradually decreases with distance from the massive ore mound, from more than tens
of centimeters to a few millimeters. The clastic sediments are characterized by good preservation of sulfide material composed
of hydrothermal sedimentary colloform pyrite, chalcopyrite with lamellae of relict isocubanite, and concentrically zoned sphalerite.
Numerous pyrite framboids, nodules, and euhedral crystals; chalcopyrite segregations; and twinned sphalerite are typical of
sulfide-bearing black shale. Enargite, tennantite, and galena were formed after pyrite, filling interstices between nodules
or partially replacing and corroding the previously formed minerals. The interrelations between minerals show that the fine-clastic
sulfide-bearing black shale underwent diagenesis in the presence of organic matter. 相似文献
14.
P. Halbach N. Blum U. Münch W. Plüger D. Garbe-Schönberg M. Zimmer 《Mineralium Deposita》1998,33(3):302-309
In December 1993, the first massive sulfides were recovered from the Indian Ocean floor, north of the Rodrigues Triple Junction.
The polymetallic deposit is situated in the fourth Central Indian Ridge segment, close to the rift axis; it is hydrothermally
no longer active. The deposit appears to be typical of mid-ocean ridge massive sulfide occurrences but is in a phase of disintegration
and about to be buried by sediment. The chimney structures were formed by multiple hydrothermal events and are now degraded
by mass wasting showing various stages of weathering. Later-stage, low-temperature hydrothermal mineralization processes led
to copper and gold enrichment. Here we report on the geological setting, mineral zonation, different sulfide types and stages
of formation of the “Sonne Sulfide Field”, which is part of a larger mineralized zone.
Received: 20 October 1997 / Accepted: 4 December 1997 相似文献
15.
VMS矿床成矿流体的组成,来源及作用机制 总被引：5，自引：1，他引：5
ＶＭＳ矿床是一类非常重要的有色金属矿床，其成因与火山岩及海水密切相关。流体包裹体成分及氢氧同位素特征表明成矿流体主要为加热的海水，可能有岩浆水的参与。渗入火山岩层的海水在深部热源作用下发生对流，并萃取了火山岩中的金属。成矿流体在海底喷溢，与海水混合反应，造成矿石沉淀。整个成矿演化过程经历了复杂的流体—岩石反应和流体—流体反应，这些反应在成矿中起着非常重要的作用。 相似文献
16.
Sedimentary-hosted polymetallic massive sulfide deposits of the Kebrit and Shaban Deeps,Red Sea 总被引：1，自引：0，他引：1
Massive sulfides recovered from the Kebrit Deep carbonaceous sedimentary succession represent black smoker fragments, novel to any Red Sea brine pool deposit. Chimneys, which were also observed in situ near the seawater/brine interface of the Kebrit Deep pool, are primarily comprised of Fe-, Zn- and Pb-bearing phases, and are often tar and asphalt impregnated. Cu-sulfides are virtually absent from parageneses, contrasting rift-related smoker and Red Sea metalliferous sediment deposits. Concentration of nickel in discrete bravoite points to a basalt/seawater leaching process as a source for most metals. The sedimentary package, which probably hosts Cu-mineralization in lower stockworks of the smoker deposit, is considered the major source of lead. Prevention of boiling of hydrothermal fluids, passing through a succession of organic-rich carbonate and clay horizons prior to discharge, is essential for smoker formation. Shaban Deep sedimentary-hosted massive sulfides are less frequent, with pyrite being the dominant ore mineral. Sulfur isotope data indicate both high temperature inorganic as well as biogenic sulfate (seawater and/or evaporite) reduction in sulfide-forming processes. Cogenetic sulfates formed from residual, bacteriogenically reduced seawater sulfate. Rather low sulfide/sulfate precipitation temperatures of 110–130 °C for the Kebrit brine pool and 100 °C for Shaban Deep massive sulfides are evident. 相似文献
17.
To characterize the hydrothermal processes of East Pacific rise at 9o-10oN, sulfide mineral compositions, textural, and geochemical features of chimney ores were studied using ore microscope, scanning electron microscope, X-ray diffraction analysis, and electron microprobe techniques. Results show that there are three mineral assemblages for the hydrothermal chimney ores, namely: (i) anhydrite marcasite pyrite, (ii) pyrite sphalerite chalcopyrite, and (iii) chalcopyrite bornite digenite covellite. Mineral assemblages, zonational features, and geochemical characteristics of the ore minerals indicate that ore fluid temperature changed from low to high then to low with a maximum temperature up to 400 ℃. The chimney is a typical black smoker. The initial structure of the chimney was formed by the precipitation of anhydrites, and later the sulfides began to precipitate in the inner wall. 相似文献
18.
河北兴隆地区硫化物黑色页岩地球化学及海底喷气成因研究 总被引：9，自引：1，他引：8
河北兴隆－宽城一带块状硫化物矿床 板发育厚度不等的纹层状硫化物黑色页岩。此类黑色页岩Ｚｎ的质量分数平均为４．０４％,Ｓ的质量分数平均为１１．７３％,其中闪锌矿,黄铁矿均呈纹层状赋存在黑色页岩内。 相似文献