The Nova-Bollinger Ni-Cu sulfide deposit is associated with a small chonolith (tube-shaped) intrusion emplaced at lower crustal depths into granulite facies migmatite gneisses. The deposit comprises disseminated and net-textured ores within the intrusions and a high proportion of massive, semimassive, and breccia exocontact ores within the underlying country rocks. Internally disposed endocontact ores show typical magmatic textures including conventional net texture, leopard net texture characterized by the presence of centimeter-sized clots of olivine and intercumulus phases, and globular ores. Some of the globular ores show an association of sulfide blebs with clinopyroxene-carbonate intergrowths that may represent infilling of original CO₂-rich vapor bubbles. The exocontact ores have an assemblage of textures indicative of emplacement into hot, soft country rocks at a large-scale melting-infiltration front. Characteristic features range from hard-walled extensional vein arrays to complex infiltrations of disseminated sulfide within chaotically folded paragneiss. Sulfide infiltration was accompanied by partial melting of the country rock, producing felsic leucosomes, some of them strongly enriched in garnet, mainly occupying vein walls and interpreted as the result of counterflow of displaced silicate partial melt. Coarse-grained pentlandite-chalcopyrite-pyrrhotite loop textures are characteristic of all ore types, down to the scale of the infiltrating sulfides within the gneisses, and are regarded as diagnostically magmatic textures generated by sulfide liquid fractionation and growth of high-temperature pentlandite by peritectic reaction between fractionated sulfide melt and early crystallized monosulfide solid solution. The highly distinctive features of the Nova-Bollinger ores are a consequence of their emplacement in the mid to lower crust under peak granulite facies conditions. Under these unusual conditions the timescales for cooling between the silicate solidus and sulfide solidus temperatures were of the order of millions of years, being controlled by the temperature-time path for the exhumation of the orogen as a whole. Sulfides solidified over a time period three orders of magnitude greater than the thousand-year timescale for the solidification of the host silicate magmas. Furthermore, timescales for deformation matched those for cooling and solidification, allowing the country rocks to undergo deformation during ore emplacement. Fluctuating strain rates during and after initial emplacement of the carrier magmas into the host intrusion caused episodes of brittle extension, allowing unusually efficient penetration of partially molten sulfide into heterogeneous, partially molten silicate country rock, resulting in an unusually extensive thermomechanical aureole compared with other mafic intrusion-hosted nickel systems globally.

中文翻译：

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西澳大利亚州奥尔巴尼-弗雷泽造山带的Nova-Bollinger Ni-Cu-Co矿床中的硫化物赋存和迁移

Nova-Bollinger Ni-Cu硫化物矿床伴随着一个较小的脉石（管状）侵入体，该侵入体在地壳较低深度处进入了粒岩相的辉长岩片麻岩中。该矿床包括侵入岩中的散布的和网状的矿石，以及下伏的乡村岩石中大量的块状，半块状和角砾岩外露型矿石。内部放置的内接触矿石显示出典型的岩浆质地，包括常规的网状质地，以橄榄石和积云相的厘米大小的凝块的存在为特征的豹网状质地，以及球状矿石。一些球状矿石显示出硫化物起泡与斜辉石-碳酸盐共生物的关联，这可能代表了原始CO _2的填充富含蒸气的气泡。接触矿石具有多种结构，表明在大规模的熔渗带前沿已进入热的软质岩石。特征范围从硬壁延伸静脉阵列到混乱折叠的帕拉尼戈斯病中散布的硫化物的复杂渗透。硫化物的渗入伴随着乡村岩石的部分熔融，产生了长英质的白质体，其中一些富含石榴石，主要占据了静脉壁，并被解释为置换的硅酸盐部分熔融体逆流的结果。粗粒状的膨润土-黄铜矿-硫铁矿环状纹理是所有矿石类型的特征，直至片麻岩中浸渗硫化物的大小，并且被认为是硫化物液体分馏和分馏后的硫化物熔体与早期结晶的单硫化物固溶体之间的包晶反应生成的高温五方晶生长的诊断岩浆质地。Nova-Bollinger矿石的高度鲜明特征是在高峰粒岩相条件下将它们置于中下地壳的结果。在这些异常条件下，硅酸盐固相线和硫化物固相线温度之间的冷却时间尺度约为数百万年，这受造山带整体发掘的温度-时间路径的控制。硫化物在比主体硅酸盐岩浆凝固一千年的时间尺度大三个数量级的时间内凝固。此外，变形的时间尺度与冷却和凝固的时间尺度相匹配，从而使矿石在放置矿石时发生变形。载体岩浆初次进入宿主侵入过程中和之后的应变速率波动会导致脆性扩张，从而使部分熔融的硫化物异常有效地渗透到非均质部分熔融的硅酸盐乡村岩石中，与其他镁铁质岩相比，形成异常广泛的热机械金刚砂全球入侵托管镍系统。