[BCG09-P06] Change of the carbon cycle in G-L boundary using numerical value calculation
Keywords:GL boundary, Carbon cycle, extinction
There were many previous studies of carbonate and organic carbon isotope ratio from GLB to PDB. The carbon isotope records show over +6 permil before GLB, calling to Kamura event. The d13Ccarb after Kamura event decrease to ca. 0 permil around GLB. Moreover, the d13Ccarb decreases from ca. +3 permil to ca. -2 permil at PTB and shows large excursions from PTB to middle Triassic (Isozaki et al., 2007a,b; Korte et al., 2005a,b; Payne et al., 2008). On the other hand, organic carbon isotope date show about -30~-28 permil in deep sea sediment (NIshikane et al., 2014). And decoupled carbonate and organic carbon isotope ratio is observed in Iwaizaki carbonate section, South of Kitakami belt. The section corresponds to the Kamura event before GLB (Tobita et al., in prep).
We discuss the change of carbon cycle to reproductive carbonate and organic carbon isotope changes by the numerical value calculate.We assume an inorganic and an organic reservoir in the sea. Flows (Photosynthesis and Remineralization, organic burial, carbonate burial) are a ratio of each reservoir’s size.The results suggested changing amount of organic matter in GLB. The changes might be triggered by large extinction.The large organic matter might cause a global expansion of oxygen minimum zone (OMZ).