Temporal variation of water content in the lower continental crust: Evidence from feldspar in mafic granulites
DOI:
CSTR:
Author:
Affiliation:

Clc Number:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
  • |
  • Comments
    Abstract:

    Water contents and chemical compositions of normal anhydrous minerals from Early-Paleozoic Songshugou and Tongbai terrain granulites and Paleo-proterozoic Junan granulite xenoliths were obtained by Fourier transform infrared spectrometer (FTIR) and electron microprobe (EMP) respectively. All granulites characterized by mafic nature were formed under the lowest crustal conditions. Plagioclases in granulites contain trace amounts of water in the form of structurally bound hydroxyl and less molecular water. Water contents (H2O wt.) of plagioclase range from 465×10-6 to 733×10-6 at Songshugou, from 210×10-6 to 993×10-6 at Tongbai, and from 717×10-6 to 1 239×10-6 at Junan, respectively. Combined with previous results for Paleo-proterozoic granulites (Junan and Nushan xenoliths and Hannuoba terrain) and Mesozoic granulites (Daoxia and Hannuoba xenoliths), it seems that water contents in the lower continental crust of eastern China were variable with time. Water contents of Paleozoic and Proterozoic granulites are much higher than those of the Mesozoic granulites and there is no difference between Paleozoic and Proterozoic granulites,implying the existence of a more hydrous lower continental crust of eastern China before Mesozoic.

    Reference
    Related
    Cited by
Get Citation

杨贵才,杨晓志,夏群科,2012,下地壳含水性的演化 ——来自不同时代麻粒岩中长石水含量的证据[J].岩石矿物学杂志,31(4):565~577. YANG Gui-cai, YANG Xiao-zhi, XIA Qun-ke,2012,Temporal variation of water content in the lower continental crust: Evidence from feldspar in mafic granulites[J]. Acta Petrologica et Mineralogica,31(4):565~577.

Copy
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:May 25,2011
  • Revised:May 17,2012
  • Adopted:
  • Online:
  • Published:
Article QR Code