鞍本抚顺地区科马提岩的初步研究

A PRELIMINARY STUDY OF KQMATIITES IN ANSHAN-BENXI-FUSUN REGION,NORTHEAST CHINA

Komatiites have been discovered for the first time in the Lower Anshan Group with a metamorphic grade from amphibolite to granulite facies. Komatiites occur as bedded ultramafic volcanic rocks on the ocean-floor. The kematiites in the Region occurring in the metamorphic rocks are some monomineralic rocks such as hornblendite, monoclinie augitite and hypersthenite. Local komatiites are found retaining some typical pre-existing structures and textures of volcanic rocks, such as blastophitie texture and blastospinifex. The chemical composition of komatiites in this region is much similar to that of other well-known model komatiites in the world, and so are their geochemical charaeteristies. The occurrence of komatiites in the Anshan-Benxi-Fusun Region provide strong evidence to show that this region is an Archean greenstonc belt. Studies on komatiites in this region will shed much light on the stratigraphic division of the Anshan Groupand the paleostructure of the greenstone belt as well as on the rules governing metallogenesis in the Anshan-Benxi-Fusun Region.

Komatiites have been discovered for the first time in the Lower Anshan Group with a metamorphic grade from amphibolite to granulite facies. Komatiites occur as bedded ultramafic volcanic rocks on the ocean-floor. The komatiites in the Anshan-Benxi-Fusun Region occurring in the metamorphic rocks are some monomineralic rocks such as horn-blendite, monoclinic augitite and hypersthenite. Local komatiites are found retaining some typical pre-existing structures and textures of volcanic rocks, such as blastophitic texture and blastospinifex. The chemical composition of komatiites in this region is much similar to that of other well-known model komatiites in the world, and so are their geochemical characteristics.The occurrence of komatiites in the Anshan-Benxi-Fusun Eegion provide strong evidence to show that this region is an Archean greenstone belt. Studies on komatiites in this region will shed much light on the stratigraphic division of the Anshan Group and the paleostructure of the greenstone belt as well as on the rules governing metal-logenesis in the Anshan-Benxi-Fusun Region.