摘要
全岩－矿物的锶同位素研究结果表明，出露在张广才岭花岗岩带上的新华屯岩体属中侏罗世晚期的产物，其同位素年龄为１６０～１６５Ｍａ，表明该晶洞花岗岩体不属于印支期。地球化学研究结果显示，该岩体属于长英质“Ｉ”分异型，并在岩体就位和岩浆结晶过程中存在少量地壳物质的混染，但控制岩体成分变化的主要因素仍是矿物的结晶分异作用。年轻的钕同位素模式年龄表明该区存在新元古—显生宙的地壳增生。
The whole rock and mineral Rb-Sr isotopic dating suggests that the Xinhuatun pluton located in Zhangguangcailing of Northeast China was emplaced in Middle Jurassic with isotopic ages of 160～165Ma, rather than belonging to Indosinian. Geochemical studies indicate that this pluton is of fractionated felsic I_type and experienced slight contamination by crustal material during its emplacement and crystallization. However, the major factor responsible for chemical variation seems to have been mineral fractionation. The young Nd model ages suggest a significant crustal growth in the period of Neoproterozoic-Phanerozoic.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
1998年第3期226-234,共9页
Acta Petrologica et Mineralogica
基金
教育部(原国家教委)优秀青年教师基金
留学回国人员基金
博士点基金
