摘要
山东半岛东部变质岩中的角闪石分为角闪岩相岩石中的和麻粒岩、榴辉岩中的，均属钙质角闪石。角闪石的Ｍｇ、Ｃａ含量主要受寄主岩石控制，而Ｓｉ、ＡｌⅣ、ＡｌⅥ、Ｔｉ、（Ｎａ＋Ｋ）含量主要受变质温压条件控制。随变质温度的增高，ＡｌⅣ、Ｔｉ、（Ｎａ＋Ｋ）增高，Ｓｉ减少，随变质压力的增高ＡｌⅥ增高。低角闪岩相的角闪石形成于５２０～６００℃、０．４６～１．０４ＧＰａ的温压条件下，高角闪岩相的角闪石形成于６５０～７００℃、０．７５～０．８９ＧＰａ的温压条件下。麻粒岩和榴辉岩中退变质阶段的角闪石主要形成于中压相系角闪岩相的温压条件。
The amphiboles in metamorphic rocks from Eastern Shandong Peninsula can exist in those of the amphibolite facies rocks, the granulite and eclogite. They all belong to calcic amphibole. Mg and Ca components of the amphibole are mainly controlled by their host rocks, while Si, Al Ⅳ, Al Ⅵ, Ti and (Na+K) components are mainly controlled by the temperature and pressure of metamorphism. With the increase of metamorphic temperature, Al Ⅳ, Ti, (Na+K) increased, while Si decreased. With the increase of metamorphic pressure, Al Ⅵ increased. Using Hb-Pl, Gr-Hb and Gr-Bi geothermometers and geobarometers, pT conditions of formation of the amphiboles obtained are 520￣600℃ and 0.46￣1.04 (mostly 0.57￣0.87) GPa for those in lower amphibolite facies; 650￣700℃ and 0.75￣0.89 GPa for those in higher amphibolite facies. The amphiboles of retrogressive metamorphic stages in the granulite and eclogite were mainly formed under the condition of amphibolite facies of medium pressure facies series.
关键词
山东半岛
变质岩
钙质角闪石
化学成分
Eastern Shandong Peninsula, metamorphic rock, calcic amphibole, chemical composition, pT condition
