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泡沫塑料吸附法(下称泡塑吸附法)是新开展起来的一种泡沫塑料为载体吸附多种金属元素的找矿方法,是金矿化探中行之有效的手段。本文将从一些实际找矿效果来说明泡塑吸附法找金的发展前景。泡塑吸附法及其应用效果(一)方法原理金在白然界中以分散状态存在为其特征,可分为原生金和表生金两部分,而在各种类型金矿上方及其周围土壤中,金几乎均以自然金和极少量的金络合物、金有机化合物等方式存在,并且能溶于王水和碱性氰化物中。土壤中微量金和王水化学反应形成氯金酸反应式为: 相似文献
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金矿化探异常评价的几个问题 总被引：8，自引：1，他引：8
近年来,化探方法找金取得了好的效果,这是因为:①解决了痕量金的快速分析方法,将金的分析灵敏度提高到0.5ppb,这是“依金找金”扩大找矿靶区十分关键的一步;②初步提出了一套评价金异常的方法(尽管尚不十分完善)。估计这种化探方法找金的“效果优势”在今后几年内还将持续。但是,也应该看到,根据化探异常未找到金矿的例子也不乏有之,例如,化探异常 相似文献
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表面活化吸附体野外预富集—测定团结沟天然水中的微量金 总被引：1，自引：0，他引：1
在实验室中,利用聚氨酯泡沫塑料预富集—测定岩石、土壤和水系沉积物等地质物料中的微量金,已取得成功。该方法最早由鲍恩提出,1976年国内有人用于金的测定,但将此方法用于野外预富集—测定天然水中的微量金,目前尚未见报道。现用于富集天然水中微量金的方法有共沉淀法(Boyle,1979)、共结晶法(Weiss和Lai,1963)、离子交换树脂收集法(Brooks,1960;Chao,1971)、氯化汞富集法(Jenne等,1968)和蒸发法(Mchugh,1984)。这些方法的共同特点是野外操作烦琐,工作效率较低,因而限制了实际应用。 相似文献
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长期以来对金的矿源层讨论很多,那种把地层金含量作为判定金源层的唯一标准的观点已被摒弃,越来越多的人已使用金含量分析值的数理统汁分析、金的存在形式研究等方法来探讨地层对金成矿的贡献,进行金源层的判别。地层中金的存在形式及活动性是决定地层能否成为金源层的重要因素,对这一问题前人已有了一定的看法。如Keays(1975)认为赋存于硫化物和矿物颗粒之间的金易于活化,可称为有效金,而存在于矿物晶格中的金一般不易活化,为非有效金。朱祥坤(1990)等提出在岩石的淋滤和变质过程中易于活化释放的金称为有效金,而不易于释放的那部分金为非有 相似文献
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金的赋存形式及其有关地球化学问题 总被引：1，自引：0，他引：1
在地质作用不同阶段中,金的赋存状态也不同。其变化规律决定于金本身的地球化学性质,因此讨论其赋存状态时必须从金的地球化学性质入手。本文试图阐明金的赋存形式,形成机理及其研究方法。一、金的主要地球化学特征金的原子序数79,属第六周期I_B族元素(Cu、Ag、Au)。原子结构5S~2 5P~6 5d~(10)6s~1,是镧系之后的过渡元素,原子的电子充填方式为内层充填,表现亲Fe(Pt)性和亲Cu(S)性。充填方式也决定了金的主要地球化学参数—电离势、(9.22电子伏特)、负电性(2.3)、氧化—还原电位(Au~ e=An 1.68V,Au~(3 ) 3e=Au 1.42V)—“三高”的特点,因而金的化学性质显惰性,常呈自然金出现。 相似文献
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堆浸法提金一般是将低品位(0.8×10~(-6)—3×10~(-6)矿石破碎,堆积在由防渗材料铺筑的堆矿场上,用稀的碱性NaCN溶液在矿堆上喷淋,使金(银)溶解。贵液从矿堆中渗滤出来,流入矿堆周围的沟中,再流入贵液池内。用活性炭吸附或锌粉置换沉淀法从贵液中回收金,贫液再反回矿堆,循环进行,直至各堆浸场金浸出完成为止。堆浸提金的这种方法仍然是技术上还很年轻的提金工艺,与其他方法一样,人们同样会提出那些与成本、回收率等有关的问题。所以该工艺被应用以来,人们就不间断地寻找改进工艺、提高回收率、降低 相似文献
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对几条前寒武纪矿脉内金的分布形式的深入研究,可以使人们找到一些新的方法来探查有价值的金矿化.南非矿山联合会研究组织正在进行一些研究工作以确定金最初是如何沉淀下来以及鉴定与金富集有关的其它特征.该研究组织以三种不同的方法在矿脉上采样:(1)采集和评价整体样品;(2)收集和分析附近的组合样品;(3)用X-射线检查无数片岩石样品来确定其中所含金颗粒的位置.组合样品分析和X-光照片揭示出,金的沉积是不规则的,在几厘米之内就变化很大.然而,整体样品的分析结果却表明,一大块样品内金的 相似文献
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CCSD主孔揭示的东海超高压榴辉岩中的金红石：微量元素地球化学及其成矿意义 总被引：18，自引：15，他引：18
金红石是榴辉岩中的主要含钛副矿物。中国大陆科学钻探工程主孔100-2000m岩心样品中,金红石榴辉岩、多硅白云母榴辉岩和蓝晶石榴辉岩中都程度不等地含有金红石。金红石既可以与其它矿物一起包裹在主要变质矿物中,也可以呈粒间矿物,但在榴辉岩经受角闪岩相退变质作用过程中,金红石亦会退变为榍石。本文利用电子探针除了分析了金红石的主要元素外,还仔细测量了Nb、Cr、Zr含量。结果显示,Nb平均含量为147ppm,最高含量为670ppm,Cr的平均含量为614ppm,最高含量为3630ppm,低Nb特征(<1000ppm)显示榴辉岩原岩为镁铁质岩石;此外,三类榴辉岩也具有不同的金红石Nb、Cr地球化学特征,即金红石榴辉岩中的金红石表现为低Cr(<500ppm)、Nb变化大(0-670ppm)的特征,多硅白云母榴辉岩中的金红石以中等Cr含量(500-1200ppm)、Nb变化较大(0-480ppm)为特征,而蓝晶石榴辉岩中的金红石显著富Cr(2000-3630ppm),而Nb则非常贫乏(<140ppm)。在总共289个金红石Zr含量数据中,大部分Zr含量分布在150-240ppm之间,均值约为200ppm;利用Zacketal.(2004)提出的金红石温度计,计算得到金红石的形成温度介于690℃和7870℃之间。研究结果表明,金红石的微量元素分析是研究榴辉岩原岩特征及其钛成矿作用的实用方法之一。 相似文献
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Phase relations in the system NaAlSiO4-NaGaSiO4 to 945° C at 1 kbar P(H2O) are dominated by stability of Na(Al,Ga)SiO4 with the beryllonite-type structure. The nepheline structure is restricted to NaAlSiO4-rich compositions at moderate and high temperature. Structure-composition relationships are controlled by space-fitting requirements of both framework and cavity cations, as in related systems. The two-phase (nepheline-type+beryllonite-type) field has been delineated from the end-member NaAlSiO4 composition up to the peritectic point at about 945° C (and 60 mol% NaGaSiO4), using a volume-composition relationship for the beryllonite-type phase, phase appearance, and electron microprobe analysis. At end-member NaGaSiO4 composition, the beryllonite-type phase is stable to the melting point (902±5° C). At end-member NaAlSiO4 composition, the beryllonite-type?nepheline-type transformation occurs at 348±2° C, and is associated with an increase in molar volume of 2.4% and enthalpy of 5170±40J·mol?1. Thus, end-member NaAlSiO4 nepheline, and probably all sub-potassic nephelines as well, are metastable at very-low geological temperatures. 相似文献
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《International Geology Review》2012,54(10):1308-1336
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We present a Raman spectroscopic study of the structural modifications of several olivines at high pressures and ambient temperature. At high pressures, the following modifications in the Raman spectra are observed: 1)?in Mn2GeO4, between 6.7 and 8.6?GPa the appearance of weak bands at 560 and 860?cm?1; between 10.6 and 23?GPa, the progressive replacement of the olivine spectrum by the spectrum of a crystalline high pressure phase; upon decompression, the inverse sequence of transformations is observed with some hysteresis in the transformation pressures; this sequence may be interpreted as the progressive transformation of the olivine to a spinelloid where Ge tetrahedra are polymerized, and then to a partially inverse spinel; 2)?in Ca2SiO4, the olivine transforms to larnite between 1.9 and 2.1?GPa; larnite is observed up to the maximum pressure of 24?GPa and it can partially back-transform to olivine during decompression; 3)?in Ca2GeO4, the olivine transforms to a new structure between 6.8 and 8?GPa; the vibrational frequencies of the new phase suggest that the phase transition involves an increase of the Ca coordination number and that Ge tetrahedra are isolated; this high pressure phase is observed up to the maximum pressure of 11?GPa; during decompression, it transforms to a disordered phase below 5?GPa; 4)?in CaMgGeO4, no significant modification of the olivine spectrum is observed up to 15?GPa; between 16 and 26?GPa, broadening of some peaks and the appearance of a weak broad feature at 700–900?cm?1 suggests a progressive amorphization of the structure; near 27?GPa, amorphization is complete and an amorphous phase is quenched down to ambient pressure; this unique behaviour is interpreted as the result of the incompatibilities in the high pressure behaviour of the Ca and Mg sublattices in the olivine structure. 相似文献
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Solid solubility and structural phase transitions in (Ca
x
Sr1-x
)TiOGeO4have been studied by means of in situ high temperature X-ray powder diffraction. The displacive A2/a–P21/a phase transition analogous to titanite has been followed across the solid solution. Strain analysis indicates a transition
temperature of T
c=594 ± 10 K for SrTiOGeO4 and the additional occurrence of an isosymmetric anomaly at T
i
=800 ± 25 K, in analogy to the isomorphous compound CaTiOGeO4. Lattice parameters as a function of temperature and composition have been determined by X-ray powder diffraction between
room temperature and a maximum temperature of 1123 K. The e
11 and e
13 components dominate the strain tensor. All compositions across the solid solution exhibit close to tricritical phase transitions
P21/a–A2/a. The critical temperature remains almost unaffected by substitution of Sr for Ca, but the magnitude of the spontaneous strain
drops significantly with even small amounts of Sr present. 相似文献
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The limit of solid solution of SiO2 in nephelines has been determinedat 700? C and a water pressure of 15, 000 lb/sq. in. X-ray dataare given for the determination of the composition of nephelinesin equilibrium with alkali feldspar at 700? C. The break in the plot of lattice parameters against chemicalcomposition for nephelines in the system NaAISiO4–KAISiO4(Tuttle & Smith, 1958) is found to persist in the ternarysystem and occurs when six out of the eight alkali atom sitesare filled by Na. 相似文献
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