铬铁岩

A group of mantle minerals containing about 70～80 subtypes of minerals have been discovered from podiform chromitite s in the Luobusa ophiolite, Tibet, China, in which the alloys attract the attention of geologists.

从西藏雅鲁藏布江蛇绿岩带的罗布莎豆荚状铬铁矿床中，揭示出包含 70～ 80种矿物的一个地幔矿物群，其中特别引人注意的是含有多种合金。

This study wants to perform researches on the Kangjinla chromitite and its host rock-mantle peridotite, to determine the existence of special mantle minerals, to discuss the origin of the chromtite and mantle peridotite together with the genetic relation between them.

本论文拟开展罗布莎地幔橄榄岩体中的康金拉铬铁矿床及其围岩地幔橄榄岩的研究，查明该铬铁矿矿体，尤其矿体围岩的地幔橄榄岩中是否也存在金刚石等特殊地幔矿物；通过详细的矿物学和岩石学的研究，探讨铬铁矿和地幔岩的成因，以及两者之间的成因联系。

The deep origin of Kangjinla podiform chromitite is suggested by: that for the Kangjinla chromitite and the mantle peridotite rocks, the compositions of the chrome spinel, olivine and clinopyroxene are rather different, which indicates that the chrome spinel in the chromitite is neither the simple concentration of that in the host rocks nor with certain genic relation with mantle peridotite. Though the chromitite might be exotic for host rocks, both of them were carried from deep mantle to the shallow place by mantle plum.

康金拉铬铁矿石与矿体围岩地幔橄榄岩的铬尖晶石、橄榄石和单斜辉石等成分方面明显不同，认为矿石铬尖晶石并非是由副矿物铬尖晶石富集而成，与地幔橄榄岩也不存在成因联系，认为豆荚状铬铁矿床对于近矿围岩地幔橄榄岩而言为外来体，但两者可能均是由地幔深部被地幔柱带到上部。

For a 1116Kg chromitite and a 384Kg mantle peridotite sample, by heavy mineral separation and picking up under a binocular microscope following productions are obtained: the UHP minerals including moissanite and over 1000 diamond grains are discovered firstly from the Kangjinla chromitite orebody Cr-11, which is far more abundant than the Luobusa district; a series of unusual mantle minerals like moissanite and a great deal of diamond grains are discovered firstly from the host rocks of chromitite orebody Cr-11, providing the foundation of discussing the chromitite origin and its relation with the host rocks; besides the UHP minerals like moissanite and diamond, various special mantle minerals are revealed from the chromitite orebody Cr-11 and its host rocks including some native elements, alloys, oxides, sulphides, silicates, carbonates, and tungstates.

2人工重砂发现铬铁矿和地幔橄榄岩中的金刚石等特殊地幔矿物。1116 Kg铬铁矿和384Kg地幔橄榄岩大样经人工重砂分选和双目显微镜下挑选矿物，取得如下成果：首次在康金拉11号铬铁矿体中发现了上千粒金刚石，以及碳硅石等强还原环境的超高压矿物，数量远远超过在罗布莎铬铁矿矿区中发现的金刚石；首次在康金拉11号铬铁矿矿体的近矿围岩中发现了大量金刚石和碳硅石等一批异常地幔矿物，为探讨铬铁矿的成因及与近矿围岩地幔橄榄岩的关系奠定了基础；除挑选出金刚石和碳硅石等超高压矿物，在康金拉11号铬铁矿矿体与围岩地幔橄榄岩中还发现了自然铁球、金属互化物、氧化物、硫化物、硅酸盐等一批异常地幔矿物。

A very complicated mantle mineral group including the native iron and wustite assemblage was recently discovered in chromitites from the mantle harzburgite of Luobusa ophiolite, Tibet.

笔者在西藏蛇绿岩的铬铁矿石中发现了十分复杂的地幔矿物群，其中包括自然铁-方铁矿的共生组合，它们被认为是外地核和下地幔的物质通过地幔柱作用携带到上地幔的。

The mantle shear zone formed at lithospheric extensional setting of Meso-Tethys and reworked by serpentinization, cataclasis, and compressional deformation including deformed lens such as ophiolite, gabbro, and chronite, thrust faults, and folds produced during closure of the Meso-Tethys.

在南北向挤压导致海盆消亡的早期阶段，处于深层侵位环境的地幔橄榄岩由于物性的不均一性，变形分解作用产生不同尺度的透镜网络，如蛇绿岩体、辉长岩脉、纯橄岩异离体、豆荚状铬铁矿体、眼球状橄榄石、辉石残斑晶等。

For Southwestern Margin of Aqikekule Lake ophiolite, their field geological, petrological, minerological, petrochemical and geochemical characteristics show that:① it outcropped as tectonic slices along the near west-to-east strike Kunzhong fault and is composed of metamorphic perodotties, cumulates and volcanic rocks, in which, chromites are distributed in the upper part of metamorphic peridotites as pods, or in the lower part of cumulates as near-strata;② metamorphic peridotites include serpentinites, chromite-bearing serpentinites, chlorite-epidote schists and chromitites, of which, chromitites have nodular and orbicular structure, and cumulates include pyroxenits, serpentinites, chromite-bearing serpentinites, chromites and metamorphically mafic rocks and only basalts are seen in volcanic rocks;③ Cr# of chromites suggest that they formed in the SSZ and Al〓O〓 and TiO〓 of metamorphic peridotites also suggest SSZ environment;④ metamorphic peridotites have V type and enriched LREE patterns, cumulates have from strongly depleted LREE, flat REE to enriched LREE patterns with universally striking positive Eu anomalies and basalts show flat REE or slight enriched LREE patterns with no Eu anomalies;⑤ trace element and Sm-Nd isotope characteristics of metamorphic peridotites imply their strikingly heterogeneous mantle character ε〓(t+4.39～+26.20 and later Nb, Ta fertilization;⑥ trace element characteristics of basalts and their tectonic diagrams show they probably formed in the rifted island arc or back-arc basin environment.

对阿其克库勒湖西南缘蛇绿岩，野外地质、岩石学、矿物学、岩石化学以及地球化学等特征表明：①该蛇绿岩以近东西向、沿昆中断裂呈构造岩片出露，由变质橄榄岩、堆晶岩和火山岩三个单元组成，其中见铬铁岩呈豆荚状产于变质橄榄岩的上部，或呈似层状产于堆晶岩的下部；②变质橄榄岩包括蛇纹岩、含铬铁矿蛇纹岩、绿帘绿泥片岩和铬铁岩等类型，其中，豆荚状铬铁矿具有结核状构造和球状构造，堆晶岩包括辉石岩、蛇纹岩、含铬铁矿蛇纹岩、铬铁岩和变质基性岩等类型，火山岩仅见玄武岩；③铬铁矿的Cr#表明其形成在俯冲带，变质橄榄岩的Al〓O〓和TiO〓成分也指示了SSZ环境；④变质橄榄岩的稀土配分型式见V型和LREE富集型两种型式，堆晶岩表现出从LREE强烈亏损、REE平坦分布到LREE富集的配分特征，并且普遍具有醒目的正Eu异常，玄武岩的稀土配分型式表现为平坦型或LREE略富集，无Eu异常；⑤变质橄榄岩的微量元素及Sm-Nd同位素特征指示了其地幔的显著不均一性ε〓(t为+4.39～+26.20以及Nb、Ta在后期的富集；⑥玄武岩的微量元素特征及构造图解表明其可能形成在裂谷岛弧或不成熟的弧后盆地环境。

The one is refrcatory type chromite deposit which occurs in PTG lineage ophiolite, the other is metallurgical type chromite deposit which occurs in PTG lineage ophiolite.

本文还证明西准噶尔的两类蛇绿岩中发育两类豆荚型铬铁矿床；PTG系列发育耐火型铬矿床，而PPG系列则发育冶金型铬矿床。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。