摘要
辽宁赛马碱性岩位于辽东半岛东部，是我国的一个典型碱性岩区，出露面积约２８０ｋｍ￣２，其岩性较单一，主要以正长岩和霞石正长岩为主，其主体形成于早三叠纪，碱性岩浆的活动一直延续到早侏罗纪。赛马碱性岩浆起源于地幔，由幔源岩浆的结晶分异伴随着壳层物质（下地壳）的混合而形成。二元混合计算表明，赛马碱性岩相当于５３％～６１％的亏损地幔加上３９％～４７％的下地壳物质组成的混合物，在成因上为壳、幔混合型，以幔源为主。赛马碱性岩的Ｕ，Ｔｈ，ＴＲＥＥ应来源于地幔分异。
Saima alkaline rocks,distributing in the eastern part of Liaodong peninsula,cover alarge area of about 280km￣2 ,and can be subdivided into two series:syenite and nephelinesyenite. Saima alkaline rocks mainly formed in the Early Triassia and the magma activity en-ded in the Early Jurassic which the magma originated from the mantle and underwent crystal-lization defferentiation with thecombination of the material from the lower crust.So thegenesis of Saima alkaline rocks is the mixed crust- and mantle-type,the latter is the major one.
出处
《辽宁地质》
1995年第4期257-271,共15页
关键词
碱性岩
年代学
混合模型
岩浆形成
辽宁
Saima Alkdine rocks Geochronology Mixed pattern Form-ing of magma
