TITLE:
Geochemistry and Tectonic Significance of Chlorite Amphibolite in Nanfen BIF, Benxi Area, Northeastern China
AUTHORS:
Ende Wang, Changik Han, Jianming Xia, Sunggi Yun
KEYWORDS:
Chlorite Amphibolite, BABB, Nanfen BIF, Tectonic Environment, Northeastern China
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.3 No.5,
July
17,
2015
ABSTRACT: Benxi area,
Northeastern China, is the main distribution area of Archean BIF-hosted iron
deposits in China. In this area, Nanfen iron deposit is well known as the
largest open-pit iron deposit not only in China but also in Asia. So far, the
tectonic nature during Archean BIF formation period in Benxi area has been long
disputed and the tectonic setting of Nanfen BIF had not been found. In this
study, the geochemical characters of chlorite amphibolites closely associated
with BIF have been investigated for the tectonic environment of Nanfen BIF. Chlortie
amphibolites show the geochemical affinity to the back-arc basin basalt (BABB),
indicating that the tectonic environment of Nanfen BIF is the back-arc basin. In
conjunction with geological evidence of other BIFs at Benxi area, it is
identified that BIF in Benxi area might be formed in the subduction-related
back-arc basin, which provides a favorable sedimentary environment of Algoma-type
BIF.