Open AccessOxidation-reduction state of lithospheric mantle in northern Xingmeng orogenic belt
Author(s) -
LI HuaiBin,
Jianghua Feng
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/671/1/012021
Subject(s) - geology , mantle (geology) , lithosphere , peridotite , subduction , paleozoic , geochemistry , mesozoic , tectonics , petrology , paleontology , structural basin
Xingmeng orogenic belt is located in the eastern part of East Asian orogenic belt, which is a typical area of superimposition and reconstruction of multiple tectonic systems. Spinel peridotite captives have been found in Nuo Min and Kolo areas in the north of Xingmeng orogenic belt. The olivine Mg # of lherzolite is 0.895 ∼ 0.911, which is slightly smaller than that of lherzolite (0.912 ∼ 0.928), and the high Mg # of lherzolite also indicates that the upper mantle in the study area is refractory. The lherzolite and lherzolite in the study area show high fO 2 values, FMQ+1.947 ∼ 3.145, which is in sharp contrast with the relatively reduced ancient lithospheric mantle facies in general. The fundamental reason may be that the Paleozoic ancient Asian Ocean and the Mesozoic ancient Pacific Ocean successively subducted under the Xingmeng orogenic belt, resulting in the sharp rise of fO 2 in the lithospheric mantle at that time.