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陕西省略阳县铧厂沟金矿床主矿带地球化学原生晕特征及其地质意义 总被引：1，自引：0，他引：1
陕西省铧厂沟金矿是一个主要赋存于海底基性火山喷流细碧岩中的金矿床。在野外地质工作的基础上,对主矿带样品的测试数据进行了数学地质分析和原生晕分带序列计算。结果表明,Au11矿体的原生晕轴向分带序列从上至下为:Hg-Sb-Ni-As-Bi-Cu-Au-Co-Zn-W-Mo-Mn-Pb-Ag-Cd;Au8矿体的原生晕轴向分带序列从上至下为:Cu-Co-W-Au-Ni-Sb-Mn-As-Pb-Bi-Hg-Mo-Ag-Zn-Cd;并提出了主矿带理想原生晕分带序列:Sb-As-Cu-Hg(前缘晕)→Au-Ag-Bi-Pb-W(近矿晕)→Ni-Co-Mn-Mo-Zn-Cd(尾晕)。结合微量元素衬值空间变化规律,建立了2个矿体的原生晕叠加理想模型。Au11矿体在1 150 m中段以前缘晕和尾晕叠加为特征;在1 110 m中段,发育较强的尾晕。Au8矿体在1 150 m和1 070 m中段以前缘晕和尾晕叠加为特征;在1 110 m中段,矿体减薄,近矿晕减弱,发育很弱的前缘晕和尾晕。综合分析认为,Au11矿体到达中下部,向深部仍有一定延伸;Au8矿体已经接近尾部,深部可能存在新的矿体。 相似文献
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《International Geology Review》2012,54(11):37-47
Classification of endogenic ore-forming processes is based on relations existing between mineralization products and intrusions of different composition. Occurrences of contact and near-vein metamorphism are similar. By generalizing information obtained on near-vein alteration and fissure development within intrusion fields, it is possible to conclude that granitoid magmatic source of mineralization, as it grows more basic with depth, approximates gabbrodiorite in composition. Development of ore-body groups within such a field depends upon three independent phenomena: fissure-aureole, mineralization, and magmatic zoning. The classification scheme for ore-forming stages associated with magma indicates close relationship between ore occurrences and granitoid magmas of particular composition, either at the surface or at depth. --Research International. 相似文献
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N. T. Kamenikhin 《Geochemistry International》2010,48(2):163-177
The paper is devoted to the solution of a reverse problem: reproducing the zoning of ore mineralization based not on the production
of chemical elements at various depth levels (this can be done only late in the course of exploration) but by finding out
elements according to a model for geochemical zoning during early exploration phases. The model provides a basis for evaluating
the erosion level of ore mineralization based on a single section through an ore-hosting geochemical aureole. The tools used
in the calculations are pair correlation coefficients and ordered series (arranged in descending order) of the average concentrations
of indicator elements of a given mineralization type. The application of the method led to revealing rigorously defined combinations
of negative and positive pair correlation coefficients and an individual sequence of elements of the zoning in ordered series
for each level of the ore-hosting structure. Elements of zoning are distinguished among indicator elements, with the former
marking levels of ore mineralization. The relations established thereby make it possible to determine element sequence of
zoning elements of ore mineralization as a whole and the affiliation of a given section with a certain level of the ore mineralization.
The model of pair correlation reveals eight levels (from distant supraore to distant subore), and the model of ordered sequences
points to thirteen levels. The models are nonseparatable, they interact and complement each other. The proposed methods can
be applied in exploration operations at hydrothermal ore deposits with mineralogical-geochemical zoning. 相似文献
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The development of vertical zoning of wall-rock metasomatic alteration is considered with the Mesozoic Strel’tsovka caldera as an example. This caldera hosts Russia’s largest uranium ore field. Metasomatic rocks with the participation of various phyllosilicates, carbonates, albite, and zeolites are widespread in the ore field. In the eastern block of the caldera, where the main uranium reserves are accommodated, hydromica metasomatic alteration gives way to beresitization with depth. Argillic alteration, which is typical of the western block, is replaced with hydromica and beresite alteration only at a significant depth. Postore argillic alteration is superposed on beresitized rocks in the lower part of the section. Two styles of vertical metasomatic zoning are caused by different modes of deformation in the western and eastern parts of the caldera. Variations of the most important petrophysical properties of host rocks—density, apparent porosity, velocities of P- and S-waves, dynamic Young’s modulus, and Poisson coefficient—have been determined by sonic testing of samples taken from different depths. It is suggested that downward migration of the brittle-ductile transition zone could have been a factor controlling facies diversity of metasomatic rocks. Such a migration was caused by a new phase of tectonothermal impact accompanied by an increase in the strain rate or by emplacement of a new portion of heated fluid. Transient subsidence of the brittle-ductile boundary increases the depth of the hydrodynamically open zone related to the Earth’s surface and accelerates percolation of cold meteoric water to a greater depth. As a result, the temperature of the hydrothermal solution falls down, increasing the vertical extent of argillic alteration. High-grade uranium mineralization is also localized more deeply than elsewhere. 相似文献
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热液矿床原生晕具有明显的分带特征,其中含矿溶液在运动方向上显示出的轴向分带尤其重要,分带序列的建立对于评价隐伏矿体的规模、埋藏深度以及剥蚀水平有指导性意义,在很大程度上提高了地球化学找矿方法的找矿深度。针对黑龙江省三道湾子金矿,计算总结出轴向分带序列特征,确定矿体的前缘和尾晕指示元素以及分带性指数,结合矿区已知矿体对所研究矿脉剥蚀程度和深部成矿潜力进行评价。 相似文献
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DC, a multi-metal ore field, is an important and well known producer of tin in China. Besides tin, also mined are zinc, lead, antimony, copper, arsenic, tungsten, mercury, silver and many other metals. Most of the deposits in this region occur in Devonian limestones and siliceous shales. The ore deposits in this field are predominated by cassiterite sulphide type. As to the origin of those deposits, they seem closely related to biotite granite. The ore-forming material is mainly derived from magmatic rocks, and part of it may come from the host rocks. The appearance of horizontal zoning of ore deposits in this field is extremely distinct, with LXG biotite granite as the core. Found in the magmatic rocks is molybdenum mineralization. From the biotite granite outwards there displays such an occurring sequence as the following: copper (zinc) skarn ore deposits, scheelite ore deposits, wolframite ore deposits, cassiterite sulphide ore deposits, lead-zinc (antimony) ore deposits and mercury or arsenic ore deposits. In this region the mineralizing-temperature zoning is also distinguishable, basically in agreement with the horizontal zoning of ore deposits. In other words, the formation temperature of ore deposits occurring around the granite is higher than that farther away from the granite. The following mineralization periods and stages can be divided: the first period, including skarn sub-stage, cassiterite-quartz sub-stage, cassiterite-sulphide sub-stage, cassiterite-calcite sub-stage; the second period, including ferrosphalerite (galena)-franckeite sub-stage, jamesonite-boulangerite sub-stage; and the third period, including pyrite-calcite sub-stage. The characters of material composition are as follows: ore minerals are characterized by great variety, perfect crystallinity, large grain-size and abundant sulfosalts. More than 90 species of minerals have been identified. What is more interesting is that lead and antimony in some of the cassiterite-sulfide deposits are derived from jamesonite rather than galena and stibnite, which provides an example rarely encountered in metallic deposits throughout the world. 相似文献
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对矿区地表至960m中段共计6个中段平面系统采集构造地球化学样品,共采集地层和构造蚀变岩样品184件,测试了Au、Ag、As、Sb、Cu、Pb、Zn、Sn、Mo、Mn、Co、Ni、Cr、V、Ti 15种微量元素的含量,编制了各元素地球化学纵剖面图和单个矿脉元素含量曲线图,综合地球化学图件分析法和格里戈良分带指数法确定了元素的纵向、横向和轴向分带序列,建立了原生晕地球化学三维分带模式。综合地质地球化学资料分析得到:硅化砂泥岩、构造蚀变岩中Au、As、Sb、Ag元素含量高,是地壳的数倍到数百倍,变异系数大,表明这些元素卷入了成矿作用,硅化泥岩是主要的富矿围岩,而矿体大部分赋存于由于成矿热液多期次强烈活动而形成的石英岩和构造角砾岩中。矿区原生晕轴向分带序列为:As、Pb、Mo、Sn、Cu、Au、Ag、Mn、Zn、Sb。与矿体北西向侧伏规律一致,矿区地球化学异常体亦具向北西侧伏的趋势。根据元素地球化学纵剖面图中主成矿元素异常高值带向下延伸未封闭,矿体向下未尖灭、特征前缘晕元素Sb和成矿晕元素Zn出现在矿尾晕等特征说明,矿体向下仍有一定的延伸,已知矿体北西侧深部是下一步找矿勘探的重点区域。 相似文献
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青山铅锌矿床是黔西北矿集区内威宁-水城成矿亚带的典型矿床之一，矿体产出严格受构造和岩性双重因素控制。含矿断裂带中构造岩既是构造变形作用的载体，也是相应变形环境的受体，其具有显著的分带特征。针对斜落走滑构造环境下弱蚀变构造岩与热液成矿成生联系研究的薄弱环节，基于构造岩-岩相学填图方法以及不同岩相带内节理、裂隙构造解析，系统采集不同构造岩-岩相带内定向构造岩样品，进行显微构造与地球化学分析，剖析不同岩相带内构造岩类型、物质组成、内部结构、构造及其分带特征，构建了该矿床构造岩-岩相分带模式，即从矿体向外，依次为:张裂岩相带→泥化相带（一、三中段及以上）→扭裂岩相带→压裂岩相带。扭裂岩相带内发育黄铁矿化、铅锌矿化、方解石化、弱白云石化，压裂岩相带内主要发育方解石化，矿化蚀变随着远离矿体呈现出从强变弱的变化规律，成矿环境也随着温度逐渐降低，呈现氧化→弱氧化-弱还原→还原的变化特征。同时，结合宏观和显微构造应力场分析，认为矿体外侧不同类型的构造岩是在统一构造应力场作用下，因不同位置的局部应力场变化而形成的不同类型的构造岩，发育在北西向断裂下盘的次级断裂不仅控制了矿体定位和形态产状，也控制了其外侧构造岩-岩相带。 相似文献
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湖南大坳钨锡矿区构造控矿规律及其在找矿中的应用效果 总被引：10，自引：1，他引：9
从矿床特征入手,对控矿构造进行具体分析,从区内岩浆活动和区域构造应力场演化规律的角度,论证了区内构造的形成机制,探讨了构造对钨锡成矿作用和矿体空间分布规律的控制。认为区内构造的形成与岩浆多阶段脉动侵位密切相关,热液致裂和NNE向断裂的左行剪切所产生的力偶作用使控矿构造产生多次脉动活动和矿化作用,控矿构造的空间分布特征及其性质决定了钨锡矿化类型和矿脉(体)的产出特征,构造控矿具有定位性、等距性、定向性及分带性等规律,应用该规律,取得了较好找矿效果。 相似文献
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本文以２８００粒自然金的研究为基础，系统讨论了自然金的标型特征。研究指出：本矿床应具较大规模，矿区内除Ｊ＿２、Ｊ＿４角砾岩体外，其余几个角砾岩体也应有一定远景，｛１１１｝、｛１１１｝＋｛１００｝、｛１１０｝的出现可指示富矿地段，自然金晶体形态的空间分带规律可确定（岩）矿体的剥蚀深度及评价外围角砾岩体的含矿性及远景；自然金中Ｂｉ可做为找矿评价的指示元素。 相似文献
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东天山石英滩金矿田控矿构造与原生晕深部预测 总被引：4，自引：1，他引：4
新疆石英滩(西滩)金矿,前人多认为是浅成低温热液型矿床,近期在该区构造与成矿关系、矿田内东北夼、黄泥坡矿点原生晕指示元素分带序列和叠加晕研究中,发现了石英滩矿区、东北夼、黄泥坡等矿点地下不同深度均存在隐伏矿体,而三个矿区(点)的空间位置恰又与矿田内一近似椭圆的古火山机构同位,且三矿区(点)具有极其相似的地质构造、成岩(脉)成矿和原生晕特征,石英滩金矿区发现有古火山热液通道.这些控矿构造和原生晕特征反映了该金矿田成矿的特殊性,对进一步寻找和预测该区相类似的隐伏矿床(体)具有重要启示. 相似文献
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内蒙古霍各乞铜多金属矿床原生晕地球化学特征及深部成矿远景评价 总被引：2，自引：0，他引：2
通过系统采集内蒙古霍各乞铜多金属矿区第7、-9勘探线上11个钻孔的岩石、矿石样品,绘制原生晕剖面等值线图,建立垂向元素分带序列,结合该矿床指示元素的变化特征,对钻孔深部隐伏矿进行了预测。该矿床成矿元素组合为Cu-Pb-Zn,前缘晕由Hg、Sb、Cd组成,尾晕以W、As、Sn为特征。该矿床处于倒转向斜的倒转翼,元素的垂向分带序列大部分为反向分带。垂向分带和指示元素的变化特征说明矿床具有多期多阶段反复叠加的特点,第7勘探线至少存在2期含矿流体,钻孔ZK702、ZK830、ZK726、ZK817深部可能有盲矿体。 相似文献
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N. S. Gorbachev 《Geology of Ore Deposits》2006,48(6):473-488
Fractional crystallization and emanation differentiation of sulfide magma and related mineralogical and geochemical zoning are exemplified in massive sulfide ores of the Oktyabr’sky deposit, Noril’sk district. The mineralogical zoning is expressed in the change of mineral types of ore from pyrrhotite (Po) to chalcopyrite (Cp) (from the flanks to the center of the ore lode). In terms of geochemistry, the Cu content, Cu/(Cu + Ni) ratio, and contents of noble metals incompatible with Mss (Pt, Pd, and Au) increase in this direction, while the S and Fe contents decrease. The distribution of elements compatible with Mss (Ir, Os, Rh, and Ru) is more complex. Their contents decrease from Po to high-Cu Cp ore, although there is a second maximum for Cb-type ore. The distribution of ore elements in the vertical and horizontal sections of massive ores at the deposit is different. The upper outer contact zone and frontal parts of massive ore lodes are enriched in all ore elements and a light sulfur isotope. The succession of enrichment is correlated with the relative affinity for sulfur and remains independent of the affinity of these elements for Mss (Pd-Rh, Os-Au). The possible role of liquid immiscibility of sulfide magma in the development of the mineralogical and geochemical zoning of massive ore is discussed. 相似文献