【摘要】：桂北龍勝地區(qū)位于江南造山帶西段,本文利用電子探針對(duì)桂北龍勝地區(qū)金車輝長(zhǎng)巖單斜輝石和斜長(zhǎng)石進(jìn)行了詳細(xì)的礦物學(xué)和礦物化學(xué)研究,研究表明單斜輝石的成分為Wo27~28En47~57Fs15~22,屬于普通輝石,斜長(zhǎng)石的成分為An1.35~9.05Ab90.34~97.45Or0.36~1.05,為鈉長(zhǎng)石。單斜輝石溫壓估算結(jié)果顯示,其形成溫度為1 250~1 350℃,該溫度基本與軟流圈地幔溫度(1 280~1 350℃)相當(dāng),其形成壓力為1.31~2.25 GPa,對(duì)應(yīng)深度為43.2~74.3 km。單斜輝石成分特征指示金車輝長(zhǎng)巖為板內(nèi)拉斑玄武巖,結(jié)合區(qū)域地質(zhì)特征,推測(cè)金車輝長(zhǎng)巖是裂谷構(gòu)造背景下軟流圈地幔物質(zhì)上涌并發(fā)生減壓熔融的產(chǎn)物。
[Abstract]:The Longsheng area of northern Guangxi is located in the western section of the Jiangnan orogenic belt. Detailed mineralogical and mineralogical studies of clinopyroxene and plagioclase in the Longsheng area of northern Guangxi are carried out by using electron probe. The results show that the composition of clinopyroxene is Wo27~28En47~57Fs15~22,. It belongs to ordinary pyroxene and the composition of plagioclase is An1.35~9.05Ab90.34~97.45Or0.36~1.05, and albite. The temperature and pressure estimation of clinopyroxene shows that the formation temperature is 1 250 ~ 1 350 鈩，

本文編號(hào)：2406998