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1.
永和磷矿氧化带银星石的矿物学特征 总被引：1，自引：0，他引：1
银星石产于永和磷矿氧化带中。该矿床面型氧化带深度5－30m，线型氧化带深度250m。在氧化带中，除碳氟磷灰石外，银星石是较常见的产物，与银星石伴生的表生磷矿还有纤磷钙铝石和磷锶铝矾等。本文研究了银星矿物的地质产状、物理化学性质，以及银星石赖于发育的氧化带地质特征，同时指出了研究银星石和磷矿氧化带对表生矿物学、磷矿床找矿勘探均有实际意义。 相似文献
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刘光碧 《矿物岩石地球化学通报》1997,(Z1)
晋宁磷矿中低品位磷块岩工艺矿物学研究刘光碧（昆明冶金研究院，昆明６５００３１）关键词晋宁磷矿磷块岩工艺矿物学研究用的矿石取自晋宁矿区的Ⅲ、Ⅳ矿段。鉴定结果表明，两矿段矿石的矿物组成基本相同，只是相对矿物含量有所不同。矿石中的磷灰石以氟磷灰石为主，另有... 相似文献
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一、概述长期来广大岩矿工作者习惯把无一定外形、具有胶状裂纹,正低偏中突起,全消光显微晶质的磷酸盐称为胶磷矿,它是磷块岩的主要矿物成分。1912年前认为胶磷矿是一种非晶质的磷酸盐矿物。1912年劳埃采用伦琴射线研究矿物内部结构,发现胶磷矿是结晶的非均质体,内部质点排列遵循晶体所共有的空间格子规律。随着多种先进测试手段综合运用于这种结晶质磷酸盐矿物的研究中,对其认识日趋统一。目前普遍认为胶磷矿主要是由超微粒状碳氟磷灰石组成,我们研究了贵州福泉震旦纪磷质迭层石、四川峨嵋震旦纪砂屑磷块岩和安微凤台寒武纪砾屑磷块岩中的胶磷矿,得到了相同结论。 相似文献
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贵州织金新华磷矿床首次发现独立的稀土矿物 总被引：1，自引：0，他引：1
产于晚震旦世和早寒武世的不少海相沉积磷矿床富含碘、稀土、钒、镍、钼等可综合利用的元素。贵州早寒武世梅树村组早期的沉积磷块岩以富含稀土元素为特征,查明其中稀土元素的赋存状态有重要的理论和实际意义。不少研究认为稀土元素主要是赋存于胶磷矿中,但由于缺少有力的实验证据,对于稀土元素在胶磷矿中的具体存在形式,仅从理论上推测稀土元素是以类质同象的形式存在。最近,我们利用电子探针对贵州织金新华磷矿稀土元素赋存状态进行研究,在胶磷矿中发现了独立的稀土矿物———方铈矿。织金新华磷矿产于早寒武世梅树村及筇竹寺阶底部含磷岩… 相似文献
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<正> 宜昌磷矿主要工业矿物为呈隐晶的氟磷灰石和碳氟磷灰石,集中呈条带状分布;主要脉石矿物有白云石、水云母、钾长石、石英等,亦聚集成与前者相间的条带。如此结构,适合重介质选矿。但一般磷矿的重介质选矿,对1mm 以下的细粒物料尚无理想的选别手段,影响了对该类型矿床的开发利用。宜昌磷矿原矿中有10%以上细粒(-1～+0mm)物料不能进入重介质选。为此,笔者对宜昌磷矿细粒物料进行了重选试验研究。重液浮沉试验及可选性分析结果表明,这部分物料,有用矿物与脉石矿物的比重差较小,采用水介质重选获得高质量磷精矿和较高回 相似文献
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华南埃迪卡拉纪磷矿的沉积环境 总被引：1，自引：0，他引：1
为查明华南埃迪卡拉纪磷矿床的沉积环境,本文选取瓮安磷矿区和开阳磷矿区作为研究对象,进行了详细的矿物学、稀土元素和铁同位素的研究。研究结果表明,瓮安下磷矿层和开阳磷矿床的磷块岩中含铁矿物为黄铁矿,显示重稀土亏损、无铈异常的特征,δ~(56)Fe显示出一定的变化范围(分别介于-0.33‰~0.27‰和0.1‰~0.54‰之间)。瓮安上磷矿层和厦安磷矿床、英坪磷矿床的磷块岩中含铁矿物为铁氧化物,δ~(56)Fe在~0‰附近,具明显的负铈异常特征。稀土元素配分方面,瓮安上磷矿层呈现出"帽子"型的配分特征,厦安磷矿床类似于现代海水的稀土配分模式,英坪磷矿床类似于热液的稀土配分模式。瓮安下磷矿层和开阳磷矿床在还原的沉积环境中形成;厦安上磷矿层、厦安磷矿床及英坪磷矿床形成于氧化的沉积环境。 相似文献
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本文重点对滇东地区原生磷块岩和风化富集磷块岩中磷灰石特征进行对比研究，总结磷灰石富集规律。首先按风化程度、矿石组分结构构造不同特点，将磷块岩划分为十种矿石自然类型。通过对不同成因类型磷灰石的化学成分分析、微量元素分析、拉曼光谱、ＥＰＲ光谱、微形态和微组构研究，根据ＣＯ，ＯＨ￣－，Ｆ￣－的含量变化，将本区磷灰石划分为四个亚种，首次总结出磷灰石不同亚种与磷块岩类型之间成因内在联系。提出氟磷灰石主要形成于风化磷块岩中，碳氟磷灰石主要形成于原生沉积磷块岩中，羟碳氟磷灰石是组成原生菌藻磷块岩主要矿物的新认识。磷灰石的富集受内外因素的控制，滇池周边原生沉积磷块岩主要以碳酸盐类磷块岩为主，这种化学活性强的矿层为本区风化富集磷矿提供了极好的物质基础，再加上该区有利的气候、地形地貌、断裂构造及水文地质条件等，形成了优质风化磷矿。 相似文献
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The variant rock types of an Alkaline-Carbonatite Complex (ACC) comprising alkali pyroxenite, nepheline syenite, phoscorite, carbonatite, syenitic fenite and glimmerite along with REE and Nb-mineralization are found at different centres along WNW-ESE trending South Purulia Shear Zone (SPSZ) in parts of Singhbhum Crustal Province. The ACC occurs as intrusions within the Mesoproterozoic Singhbhum Group of rocks. Alkali pyroxenite comprises of aegirine augite, magnesiotaramite, magnesiokatophorite as major constituents. Pyrochlore and eucolite are ubiquitous in nepheline syenite. Phoscorite contains fluorapatite, dahllite, collophane, magnetite, hematite, goethite, phlogopite, calcite, sphene, monazite, pyrochlore, chlorite and quartz. Coarse fluorapatite shows overgrowth of secondary apatite (dahllite). Secondary apatite is derived from primary fluorapatite by solution and reprecipitation. The primary fluorapatite released REE to crystallize monazite grains girdling around primary apatite. Carbonatite is composed dominantly of Srcalcite along with dolomite, tetraferriphlogopite, phlogopitic biotite, aegirine augite, richterite, fluorapatite, altered magnetite, sphene and monazite. The minerals comprising of the carbonatite indicate middle stage of carbonatite development. Fenite is mineralogically syenite. Glimmerite contains 50–60% tetraferriphlogopite. An alkali trend in the evolution of amphiboles (magnesiotaramite-magnesiokatophorite-richterite) and chinopyroxenes (aegirine augite, aegirine) during the crystallization of the suite of rocks is noted. Monazite is the source of REE in phoscorite and carbonatite. Fluorapatite has low contents of REE, PbO, ThO2 and UO2. Pyrochlore reflects Nb-mineralization in nepheline syenite and it is enriched in Na2O, CaO, TiO2, PbO and UO2. Pyrochlore containing UO2 (6.605%) and PbO (0.914%) in nepheline syenite has been chemically dated at 948 ± 24 Ma by EPMA. 相似文献
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葫芦磷矿床位于古丈背斜南西端,含磷岩系赋存于震旦系陡山沱组下部,总厚度10m、分为A—B—C—D—E—F沉积序列。矿体呈层状,产状稳定,平均厚1m。P_2O_5平均品位氧化矿石为27％;原生矿石为20％,主要由胶磷矿(氟磷灰石)和隐晶石英、以及有机碳和黄铁矿组成。磷矿形成于陆棚至陆坡的静水环境。成矿物质来自海底岩石溶解、地壳深部、海底火山和海洋生物的磷质,它们在盆地中浓缩,在化学和生物化学作用下,磷质局部富集、沉淀成矿。矿床被认为是化学和生物化学沉积成因。 相似文献
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The Itataia phosphate-uranium deposit is located in Santa Quitéria, in central Ceará State, northeastern Brazil. Mineralization has occurred in different stages and involves quartz leaching (episyenitization), brecciation and microcrystalline phase formation of concretionary apatite. The last constitutes the main mineral of Itatiaia uranium ore, namely collophane. Collophanite ore occurs in massive bodies, lenses, breccia zones, veins or episyenite in marble layers, calc-silicate rocks and gneisses of the Itataia Group.There are two accepted theories on the origin of the earliest mineralization phase of Itataia ore: syngenetic (primary) – where the ore is derived from a continental source and then deposited in marine and coastal environments; and epigenetic (secondary) – whereby the fluids are of magmatic, metamorphic and meteoric origin. The characterization of pre- or post-deformational mineralization is controversial, since the features of the ore are interpreted as deformation.This investigation conducted isotopic studies and chemical analyses of minerals in marbles and calc-silicate rocks of the Alcantil and Barrigas Formations (Itataia Group), as well as petrographic and structural studies. Analysis of the thin sections shows at least three phosphate mineral phases associated with uranium mineralizaton: (1) A prismatic fluorapatite phase associated with chess-board albite, arfvedsonite and ferro-eckermannite; (2) a second fluorapatite phase with fibrous radial or colloform habits that replaces calcium carbonate in marble, especially along fractures, with minerals such as quartz, chlorite and zeolite also identified in calc-silicate rocks; and (3) an younger phosphate phase of botryoidal apatite (fluorapatite and hydroxyapatite) related with clay minerals and probably others calcium and aluminum phosphates. Detailed isotopic analysis carried out perpendicularly to the mineralized levels and veins in the marble revealed significant variation in isotopic ratios. Mineralized zones exhibit a decrease in δ13C and δ18O isotope values and a higher 87Sr/86Sr ratio toward the center of the vein. In conjunction with petrographic studies, these changes contesting the hypothesis of a sedimentary origin for uranium and suggest a radiogenic Sr input by alkaline to peralkaline fluids from fertile granites of the end of Brasiliano/Pan-African orogeny, located outside the deposit. The origin of the phosphorous is associated with phosphorite deposits in the same depositional environment of the neoproterozoic supracrustal quartz-pelite-carbonate sediments of the Itataia Group.Considering the studies conducted here and available geological data, three main mineralizing events can be identified in Itataia: (1) an initial high temperature event connected with a sodium metasomatism-related uranium episode, taking place in Borborema Province and its African counterpart; (2) a second lower temperature stage, consisting of a multiphase cataclastic/hydrothermal event limited to fault and paleokarst zones; and (3) a third and final event, developed in frankly oxidizing conditions. The last two involving mixing of hydrothermal and meteoric fluids. 相似文献
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针对江西× ×难选胶磷矿,采用单一正浮选工艺进行试验.试验对各主要影响因素逐一研究分析,获得了最佳药剂制度,并在此基础上有针对性的进行了三组闭路试验,均获得了较满意的选别指标,满足了选矿厂的不同需求.研究结果为该胶磷矿的开发利用提供了技术支持. 相似文献
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In a series of timed experiments, monazite inclusions are induced to form in the Durango fluorapatite using 1 and 2 N HCl
and H2SO4 solutions at temperatures of 300, 600, and 900°C and pressures of 500 and 1,000 MPa. The monazite inclusions form only in
reacted areas, i.e. depleted in (Y+REE)+Si+Na+S+Cl. In the HCl experiments, the reaction front between the reacted and unreacted
regions is sharp, whereas in the H2SO4 experiments it ranges from sharp to diffuse. In the 1 N HCl experiments, Ostwald ripening of the monazite inclusions took
place both as a function of increased reaction time as well as increased temperature and pressure. Monazite growth was more
sluggish in the H2SO4 experiments. Transmission electron microscopic (TEM) investigation of foils cut across the reaction boundary in a fluorapatite
from the 1 N HCl experiment (600°C and 500 MPa) indicate that the reacted region along the reaction front is characterized
by numerous, sub-parallel, 10–20 nm diameter nano-channels. TEM investigation of foils cut from a reacted region in a fluorapatite
from the 1 N H2SO4 experiment at 900°C and 1,000 MPa indicates a pervasive nano-porosity, with the monazite inclusions being in direct contact
with the surrounding fluorapatite. For either set of experiments, reacted areas in the fluorapatite are interpreted as replacement
reactions, which proceed via a moving interface or reaction front associated with what is essentially a simultaneous dissolution–reprecipitation
process. The formation of a micro- and nano-porosity in the metasomatised regions of the fluorapatite allows fluids to permeate
the reacted areas. This permits rapid mass transfer in the form of fluid-aided diffusion of cations to and from the growing
monazite inclusions. Nano-channels and nano-pores also serve as sites for nucleation and the subsequent growth of the monazite
inclusions. 相似文献
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Daniel E. Harlov 《Mineralogy and Petrology》2011,102(1-4):77-86
Xenotime and monazite inclusions in fluorapatite megacrysts from a granitic pegmatite, Gloserheia, Froland, Bamble Sector, southern Norway are described utilizing high contrast backscattered electron imaging of cross sections of a selection of fluorapatite crystals. Electron microprobe analysis is then used to further characterize the xenotime and monazite, as well as (Y+REE) normal and depleted regions in the fluorapatite. In the (Y+REE) normal regions Y2O3 ranges from 0.4 to 1.3 whereas it ranges from below the electron microprobe detection limit to around 0.4 in the depleted regions. Low Y values in monazite (XY?=?0.01?0.05) co-existing with xenotime indicates that inclusion formation in the originally (Y+REE)-enriched fluorapatite must have occurred below 300°C. Formation of the xenotime and monazite inclusions is attributed to fluid-aided coupled dissolution-reprecipitation processes during the later stages of subsolidus cooling of the pegmatite. The fluorapatite megacrysts are hypothesized to have under gone two major fluid-induced alteration events. The first occurred sometime after crystallization was complete at temperatures below 300°C and resulted in the initial formation of the xenotime and monazite inclusions. The second occurred at some later time as the product of a relatively limited fluid infiltration, also under T?<?300°C. This resulted in the formation of (Y+REE)-depleted regions along lattice and cleavage planes while at the same time promoting Ostwald ripening of the xenotime inclusions resulting in larger grains in the (Y+REE)-depleted areas. 相似文献
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The partitioning of rare-earth elements (REEs: Gd and multiple REEs), Sr, and Mn between fluorapatite and CaF2-rich melts was investigated over a wide range of REE concentrations (i.e., from 0.8 ± 0.1 to 25,000 ± 2600 ppm Gd in fluorapatite) in two different sample assemblies (i.e., tightly covered Pt crucibles and sealed Pt capsules) at 1220 °C and atmospheric pressure. Attainment of equilibrium is indicated by selected reversal experiments. The partition coefficient D(Gd) decreases from ∼2 to ∼0.5 with increasing Gd in fluorapatite, hence a marked non-Henry’s Law behavior, but becomes independent of composition at and above ∼5000 and ∼1000 ppm Gd for experiments in Pt crucibles and Pt capsules, respectively. Non-Henry’s Law behavior is also observed in experiments involving multiple REEs. All REE patterns are convex upward in shape with maxima between Nd and Gd, and D(La)/D(Nd) and D(Nd)/D(Yb) decrease systematically with increasing total REEs in fluorapatite, suggesting that REE fractionations are partly related to non-Henry’s Law behavior. These experimental results and local structural data from previous electron paramagnetic resonance spectroscopic studies suggest that the non-Henry’s Law behavior of REE partitioning between fluorapatite and melt is controlled by intrinsic Ca2+ vacancies in the c-axis channels. The D(Sr) and D(Mn) values are independent of composition and, therefore, do not deviate from the Henry’s Law in their respective compositional ranges investigated in this study.Nonstoichiometry, such as Ca2+ and F− vacancies in the c-axis channels, is well known in natural apatites, particularly in biogenic apatites. Therefore, the observed non-Henry’s Law behavior of REE partitioning is expected to have important implications for REE geochemical modeling involving apatites and for the uptake of REEs by natural apatites. Particularly, the non-Henry’s Law behavior of REE partitioning is at least partly responsible for the commonly observed, bell-shaped REE patterns in fossil biogenic apatites. 相似文献
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The role of fluorine in submarine exhalative systems with special reference to Broken Hill,Australia 总被引：1，自引：0，他引：1
I. R. Plimer 《Mineralium Deposita》1984,19(1):19-25
Fluorine-bearing minerals are uncommon in submarine exhalative ores, exhalites and associated alteration zones, probably because of the low solubility of CaF2. The Broken Hill (Australia) deposit contains fluorapatite and fluorite with one lens containing 1.35% F and greater than 3 volume % F-bearing minerals. The calcite-fluorite-fluorapatite assemblage at Broken Hill indicates that ore deposition was probably from hypersaline fluorine-bearing fluids which decreased in pH by base leaching reactions which released Ca2+ and mixing with seawater promoting the rapid and simultaneous precipitation of calcite, fluorite and fluorapatite as a result of temperature and salinity decrease and pH and [Ca2+] increase. The abundance of fluorine minerals in the Broken Hill ore and the association of F and B minerals with stratigraphically equivalent W- and Sn-bearing exhalites suggest that F complexes are important for ore transport in some exhalative systems. The Fe/Mn ratio decreases and the F/Cl ratio increases in fluorapatite in exhalites with increasing proximity to the Broken Hill deposit. 相似文献
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Migmatites from Cone Peak, California, USA and the Satnur-Sangam road, Southern Karnataka, India contain coarser grained orthopyroxene-bearing leucosomes with subordinate biotite in finer grained hornblende-biotite-pyroxene-bearing hosts. At both localities the leucosomes are enriched in quartz and feldspar and have a higher ratio of pyroxene to hornblende + biotite compared to the host rocks. Biotite grains in leucosomes along the Satnur-Sangam road are concentrated at the margins of orthopyroxene grains and have lower abundances of Ti, Fe, and Cl and a higher abundance of F than biotite grains from the host rock. Fluorapatite grains in all rocks from both localities contain monazite inclusions similar to those produced experimentally by metasomatically induced dissolution and reprecipitation. Some fluorapatite grains at both localities are partially rimmed by allanite. The only compositional differences found between fluorapatite grains in the leucosomes and host rocks were higher concentrations of Cl in grains in leucosomes from Cone Peak. The mineralogies of the rocks suggest that the leucosomes formed by dehydration melting reactions that consumed feldspar, quartz, hornblende, and biotite and produced orthopyroxene. Allanite rims at the margins of fluorapatite grains may have formed by the later retrogression of monazite rims formed by incongruent dissolution of fluorapatite in the melt. Biotite grains at the margins of orthopyroxene crystals in the leucosomes from the Satnur-Sangam road apparently formed by retrogression of orthopyroxene upon the solidification of the anatectic melt. A similar high-grade retrogression did not affect orthopyroxene crystals at Cone Peak, indicating that H2O was removed from the crystallizing leucosomes probably in a low H2O activity fluid. Compositional differences between the paleosome and neosomes at Cone Peak are best explained by metasomatic interaction with concentrated brines while elevated Cl concentrations in fluorapatites in the leucosome suggest interaction with a Cl-bearing fluid. Brines may have been responsible for an exchange of elements between the host rock along the Satnur-Sangam road and zones of melt generation now marked by leucosomes, but fluid flow appears to have been less vigorous than at Cone Peak. 相似文献