【摘要】 <正> 鞍山地区太古代鞍山群含铁岩系的变质程度,在以往的地质工作中曾认为属于绿片岩相至角闪岩相,未见有麻粒岩相的岩石,其地层层位一般认为属中、上鞍山群的大峪沟组至樱桃园组。我们于1979年野外工作中,在鞍山小岭子铁矿西段M₂磁异常（大屯附近）发现比较典型的麻粒岩及麻粒岩相,其地质产状、岩性和岩石组合、岩石化学特征如下:更多还原

【Abstract】 The iron-bearing metamorphicseries of the Archean Ansban Groupin the Anshan area was in the pastconsidered to be of greenschist——amphibolite facies, and its stratigra-phic horizon was generally assignedto the Upper and Middle Anshan Gro-up. In 1979, the authors discoveredrelatively typical granulites at the M₂magnetic anomaly in the western sec-tion of the Xiaolinzi iron deposit,Anshan. The iron-bearing series in thearea occurs as remnants in migmatiticgranites and was intruded by theYanshanian granites. The granulitesare wall rocks of the iron ore beds.They consist mainly of two-pyroxenegranulite and hyperthene granulite.Associated granulite facies rocks incl-ude Al-rich gneiss, clinopyroxenite andhornblendite. The last two rock typesbelong to Komatiites. The originalrocks of the granulite association pos-sess the characteristics of the mafic-ultramafic volcanic rocks in the lowerparts of Archean greenstone belts.Hence, the discovery of granulites inthe deposit may serve as importantevidence and basic geological informa-tion upon which the Anshan-Benxiarea can be determined to be an Arch-ean greenstone belt, and indicatesthat the strata of the Anshan Groupin this area belong to granulite faciesand that their stratigraphic horizonis preferably assigned to the Tong-shicun Formation of the lower AnshanGroup.更多还原