TITLE
Analysis of the data in Jingwen Mao’s paper on the stable isotopes (δDH2O, δ18OH2O, and δ34S) of the gold deposits in Jiaodong Peninsula, China
AUTHOR(S)
Fa Han
ABSTRACT
In 2008, Jingwen Mao published a paper on the stable isotopes of gold deposits in the Jiaodong Peninsula. The paper has a series of problems in obtaining δDH2O and δ18OH2O of ore-forming fluids and interpreting δ34S data. ① In order to obtain δDH2O and δ18OH2O data of ore-forming fluids, Jingwen Mao selected sericite (a total of 25 samples) as the target mineral. Sericite is not an independent mineral and has no fixed molecular formula. New research has shown that it is a fine-grained aggregate composed of muscovite, illite, and sodium mica (at least muscovite and sodium mica). The water content in sericite is very complicated, including structural water, interlayer water, fissure water, primary and secondary inclusion water. Jingwen Mao extracted water from sericite by crushing, and this mixed water cannot represent the ore-forming fluids. It is unreliable to determine the source of ore-forming fluids using δDH2O measured by this kind of mixed water. ② So far, no oxygen isotope fractionation coefficient relationship between sericite and water has been obtained, whether through theoretical calculation or experimental research. In order to calculate the δ18OH2O of ore-forming fluids by measuring the δ18O of sericite, Jingwen Mao used the oxygen isotope fractionation coefficient relationship between muscovite and water for calculation, which is completely wrong. ③ The data of δ18OH2O and δDH2O of ore-forming fluids obtained by Jingwen Mao using sericite are very different from the relevant data obtained by previous researchers using quartz as the target mineral (131 samples). Based on those unreliable data, Jingwen Mao believed that the ore-forming fluids came from the mixed source of crust and mantle, while the relevant data of previous researchers proved that the ore-forming fluids came from the products of atmospheric precipitation exchanging with Jiaodong Group metamorphic rocks under different temperatures and different W/R ratios. ④ For the relationship between the high or low δ34S value of sulfide minerals and the large or small logfO2 value, Jingwen Mao’s explanation is completely opposite to the research results of Ohmoto and Wang. Ohmoto believed that the two were negatively correlated, while Jingwen Mao believed that they were positively correlated. This is a common sense mistake.
DOI
https://doi.org/10.62252/NSS.2024.1010
PAGES: 137-151
How to cite this article:
Han, F. 2024. Analysis of the data in Jingwen Mao’s paper on the stable isotopes (δDH2O, δ18OH2O, and δ34S) of the gold deposits in Jiaodong Peninsula, China. Naturalis Scientias, 1 (2): 137-151. DOI: https://doi.org/10.62252/NSS.2024.1010.