具有经济价值的铬铁矿矿床,在除非洲以外的所有大陆中,通常与属于橄榄岩—纯橄岩岩系的超基性岩阿尔卑斯型侵入体有关.关于阿尔卑斯型超基性岩的成因问题,有三种主要看法:(1)含有或不含悬浮晶体的超基性岩浆从上部地幔侵入到地壳;(2)基性(似玄武岩)岩浆从上部地幔侵入地壳,超基性岩由于它在岩浆囊中的分异作用而发生以后的分离;(3)构造地块的突起和地幔橄榄岩呈固态喷出.作者认为,全部地质资料是 The economically valuable chromite deposits are generally associated with ultramafic rock-Alpine intrusions belonging to the peridotrigite-pumice series in all continents except Africa, with regard to the genesis of the alpine ultramafic rocks , There are three main observations: (1) ultrabasic magmas with or without suspended crystals invade the crust from the upper mantle; (2) mantle (basalt-like) magmas intrude into the crust from the upper mantle, (3) the tectonic blocks of the protuberances and the mantle peridotite are solid-state spouting.According to the author, all the geological data is