摘要
本文介绍了新近在北秦岭造山带中发现的高压─超高压变质带（北带）和松树沟高压变质带（南带）代表性变质岩的化学成分、微量元素和稀土元素特征．这些高压、超高压变质岩的原岩多为基性火成岩。与北带相比，南带的高压变质岩起源于更强烈亏损的地幔，结合岩相学，同位素年龄和Ｓｍ－Ｎｄ同位素特征的差异，推测南北二带形成于不同的地质事件。产在北秦岭造山带中的高压─超高压变质岩的地球化学特征与东部产在南秦岭造山带的同类岩石有许多相似之处．推测秦岭─大别造山带从南到北是在同一个岩石圈上演化来的，不是不同地块拼接成的。
This paper deals with the characteristics of the chemical compositions, trace elements and REE of representative rocks in the recently discovered high-ultrahigh pressure metamorphic zone (the Northern zone) and Songshugou high pressure metamorphic zone (the Southern zone). The protolithes of these rocks are mainly basalt. Compared with those of the Northern zone, the high pressure metamorphic rocks of the Southern one derived from the more intensely depleted mantle. The combination of the difference in the petrography, isotope age and Sm-Nd isotope properties leads to the speculation that the two zones were formed under different geological events. Many similarities in geochemical characteristics exist in the same type of metamorphic rocks from the Northern Qinling and the Southern Qinling Orogenic Belt in the east. Therefore, it can be surmised that Qinling-Debie Orogenic Belt was not formed by coalescing different terrains, but evolved out of the same lithosphere from the South to the North.
基金
国家自然科学基金
关键词
北秦岭
造山带
榴辉岩
地球化学
相关岩石
Northern Qinling Orogenic Belt
eclogite
eclogite geochemistry
