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与科马堤岩有关的镍硫化物矿床是世界上最重要的镍矿床类型之一。除明显的上部鬣刺结构层外,坎巴尔达大部分科马堤岩蚀变强烈、斑晶难以辨认,前人将之定为“以等轴状斑晶为主的堆积层”,“没有证据说明是喷出岩还是侵入岩”,除见到某些似是而非的层间鬣刺结构怀疑存在几个岩浆旋回外,没有任何证据划分具体的岩浆旋回,所以对于各种类型镍硫化物与科马堤岩岩浆旋回的关系始终不清楚。笔者用次生磁铁矿的分布状态恢复了斑晶的形貌,研究了斑晶形状、大小、含量在剖面中的系统变化,发现科马堤岩主要形成在流动过程中,斑晶以细长条状为主,真正的“堆积层”只占1/3到1/4,其中可分数个岩浆旋回,每个岩浆旋回中,从下到上可分为堆积层、长条状斑晶结构层、鬣刺结构层、岩性相应从纯橄岩到橄榄岩到苦橄岩。下一次岩浆正好开始于块状硫化物上,滴状硫化物全部赋生在同一岩浆旋回的上部,据此笔者提出;科马堤岩的深部熔离—相继侵入—硫化作用的综合成岩成矿新模式。
Nickel sulphide deposits associated with the Komati Rock are among the most important nickel deposits in the world. Except for the obvious upper igneous structure, most of the Kamadaiyan rock swelled strongly and the porphyry crystal became illegible. The predecessors set it as “an accumulation layer dominated by equiaxed plaque.” “ Evidence states that it is either extrusive rock or intrusive rock ”. There is no evidence of specific magmatic cycle except for some plausible interbedded megalithic structures that suspect there are several magma cycles, so for all types of nickel sulphides and families The relationship between Matiyan magma cycle is not clear. The author used the distribution of secondary magnetite to restore the morphology of the porphyrin and studied the systematic changes of the shape, size and content of the plaque in the section. It was found that the komati dike mainly formed in the flow process, Strip-based, the real “accumulation” only accounts for 1/3 to 1/4, which can be divided into several magmatic cycles, each magma cycle, from bottom to top can be divided into accumulation layer, Structure layer, the structure layer of the hyenas, lithology from dunite to peridotite to picritite. The next time the magma just started on the massive sulfide, all of the dendritic sulfide was born in the same magma upper part, according to which the author proposed; deep deep dissolution of the Komati rock - one after another intrusive - sulfide diagenesis mineralization New model