贵州镇远地区含金刚石母岩再认识

Re-understanding of diamond-bearing parent rocks in Zhenyuan area,Guizhou Province

贵州镇远马坪"东方一号"岩体为中国最早发现的原生金刚石矿,受当时只有金伯利岩才含金刚石矿及后来西澳阿盖尔钾镁煌斑岩型金刚石原生矿等的影响,先后定名为金伯利岩、钾镁煌斑岩、金云火山岩等。最近专题调查分析研究表明,镇远马坪地区含金刚石母岩,其岩石学矿物学和地球化学特征均更接近澳大利亚典型金伯利岩,白坟地区岩体则类似于澳大利亚典型钾镁煌斑岩,建议将镇远马坪地区"东方一号"等岩类定名为角砾凝灰质金伯利岩,白坟地区岩类定名为钾碱镁闪石-透辉石-金云母钾镁煌斑岩,镇远地区兼有金伯利岩和钾镁煌斑岩的特征,与西澳大利亚极其类似,镇远地区乃至黔东地区具有较大的金刚石原生矿找矿勘查潜力和研究意义。

The "Eastern One" pluton in the Maping area of Zhenyuan Prefecture, Guizhou Province, is the earliest discovered primary diamond deposit. It was named kimberlite at the time of discovery, based on the traditional idea then that diamond deposits only exist in kimberlite. Later, it was named lamproite, following the discovery of Argyle lamproite type primary diamond deposit in Western Australia. Recent researches revealed that the diamond-bearing parent rocks in Maping area are closer to the Australian typical kimberlites in terms of petrological, mineralogical and geochemical characteristics, while the pluton in Baifen area is more similar to Australian typical lamproite. It is proposed that the "Eastern One" pluton in Maping area should be named breccia tuffaceous kimberlite, while the pluton in Baifen area should be kallite-diopside-flogopite lamproite. The pluton in the Zhenyuan Prefecture has the combined features of kimberlite and lamproite, quite similar to the pluton discovered in Western Australia. The primary diamond deposits in Zhenyuan area, and even in the eastern Guizhou Province, are of great potential for prospecting and research.