Junpeng Wang, Hao Deng, Timothy Kusky, Ali Polat., Comments to paper by Tang et al., 2016, PR
In a recent article, Tang et al. (2016) present interesting zircon U-Pb geochronological, geochemical, and carbon and oxygen isotopic data from the meta-carbonates of the Wanzi Group (Fuping complex) and Central Zanhuang Domain (Zanhuang complex) in the Central Orogenic Belt (named the Trans-North China Orogen in Zhao et al., 2005, 2012) of the North China Craton, and propose that these rocks formed in a proximal and shallow marine environment in the Paleoproterozoic. The zircon U-Pb data reported for the meta-carbonates by Tang et al. (2016) show age populations of 2.50–2.57 Ga, 2.2–2.4 Ga, 2.0–2.1 Ga and 1.85–1.90 Ga. The authors suggest that the depositional ages for the Wanzi Group and Central Zanhuang Domain are 1.95–1.93 Ga and 2.03– 1.90 Ga, respectively. We thank Tang et al. for providing the new geochronological measurements for future research on the Zanhuang and Fuping complexes in the North China Craton. However, based on our six years of detailed mapping and new zircon U-Pb dating of these sedimentary rocks in the Zanhuang complex, we have several major concerns. First, the authors do not present any field context for their samples, and ignore most recently published work that refutes their proposed results. Second, the quality of the data is sub-standard. Third, there is gross over-interpretation of meaningless data.