地震地质 ›› 1984, Vol. 6 ›› Issue (4): 55-69.

• 科研简报 • 上一篇    下一篇

河北平泉骆驼峰碱性玄武质角砾岩筒的岩石学特征与岩浆起源

樊祺诚   

  1. 国家地震局地质研究所
  • 收稿日期:1982-11-30 出版日期:1984-12-05 发布日期:2009-11-25

PETROLOGICAL CHARACTERISTICS AND GENESIS OF ALKALI BASALTIC BRECCIA PIPES IN THE LUOTUOFENG AREA, PINQUAN OF HEBEI PROVINCE

Fan Qicheng   

  1. Institute of Geology, State Seismological Bureau
  • Received:1982-11-30 Online:1984-12-05 Published:2009-11-25

摘要: 本文讨论了骆驼峰火山岩筒内不同源区的碱性系列玄武岩与石英拉斑玄武岩的特征。认为碱性橄榄玄武岩-碧玄岩是由石榴石二辉橄榄岩地幔(5—8%)熔融产生;橄榄霞石岩是碱性橄榄玄武岩-碧玄岩在岩石圈地幔内分异产生;石英拉斑玄武岩是岩石圈地幔的熔浆。尖晶石二辉橄榄岩是碱性玄武岩浆上升过程中捕获的地幔碎片。

Abstract: The alkli basaltic breccia pipes at the Lutuofeng area are late Tertiary volcanic rocks,composed of breccia,dikes and cones,suggesting a multi-stage volcanism.The sequence of eruption was from alkali olivin-basalts to basanite,olivine nephelites and quartz tholeiites.Based on petrography,mineralogy,major and trace elements,especially on REE and Sr isotopic composition,the petrological characteristics and petrogenetic relation of the basalts have been well discussed.It has been postulated that the alkali olivin basalt-basanite magma requires low-degree(5—8%)melting of the garnet lherzolites,while the olivin nephelites magma may be derived from differentiations of the alkali olivin basalt basanite magma under high pressure in the lithospheric mantle.The quartz tholeiites may be the products of the melts of lithospheric mantle.The author has concluded that the spinel lherzolite xenolith is mantle fragments that were trapped by alkali basalts at a time when they were uprising from the mantle.