Open AccessGeochemical characteristics of Cretaceous granitoids and their implication for tectonics in Vietnam
Author(s) -
Yang Liu,
Nianqiao Fang,
Chaojie Song
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/780/4/042053
Subject(s) - geology , cretaceous , diorite , geochemistry , leucogranite , subduction , igneous rock , pluton , basalt , tectonics , petrology , zircon , metamorphic rock , gneiss , paleontology
Vietnam is located between the Pacific subduction zone and Tethys orogenic belt. There are numerous Cretaceous granitoids in Vietnam, belonging quartz-diorite-granosyenite- granite-leucogranite magmatic series. According to geochemical data, granitoids are sub- alkaline. Samples in SV are calc-alkalic, with lower A/CNK and (Zr+Nb+Ce+Y) values, which belong to I-type granite. And those in NV are allali-calcic, with higher A/CNK values but lower (Zr+Nb+Ce+Y) values, which belong to S-type granite. Granitoids exhibit fractionated REE patterns with negative Eu anomalies, and show enrichment in LILEs and depletion in HFSEs. Because of the absence of alkaline dark-colored minerals, abundant intermediate igneous rocks and assemblage of I- and S-type granite with orogen-related geochemical characteristics, it is believed that there was compressive structure in Vietnam in Cretaceous due to Meso-Tethyan subduction.