High positive carbonate carbon isotope excursion identified in the North China Craton: Implications for the Lomagundi–Jatuli Event

Abstract

Abstract Records of the Lomagundi–Jatuli Event (LJE) are well preserved globally, but high δ 13 C carb carbonates have not been identified in the North China Craton (NCC). Our results on ~ 3–4 km thick carbonates from the newly confirmed Palaeoproterozoic successions in Fanhe Basin in the northeastern NCC show that the ~2.20–2.06 Ga carbonates have positive carbon isotope excursion and those deposited after 2.06 Ga have normal carbon isotope. Specially, carbonates from the Daposhan Formation have δ 13 C carb values of 10.2‰–11.8‰, which is the largest positive carbon isotope excursion in the NCC. The ~2.20–2.06 Ga carbonates in Fanhe Basin have similar δ 13 C carb values as those contemporaneously deposited in other cratons and their δ 13 C carb values exhibit a decreasing trend from ~2.20 Ga to 2.06 Ga. Our identification of carbonates with high positive δ 13 C carb values in Fanhe Basin not only casts new lights on records of the LJE in the NCC, but also provides important constraints on global significance of the positive δ 13 C carb excursion of LJE.