首页|Evaluation of atmospheric carbon dioxide concentrations during the Cretaceous
Evaluation of atmospheric carbon dioxide concentrations during the Cretaceous
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NSTL
Elsevier
Studying the role of atmospheric carbon dioxide concentration (pCO _2) regulating temperature during the Cretaceous is important to understand the evolution of the Cretaceous climate. However, the pCO _2 variation during the Cretaceous remains uncertain. Here we present a new paleo-pCO _2 variation record spanning the Barremian to Maastrichtian time. The new paleo-pCO _2 calculations are based on analyses of pedogenic carbonate from the Gyeongsang Basin, Korea and data from the literature on pedogenic carbonates. Our results show that the mid-Cretaceous pCO _2 levels were higher than those observed during the Early and the Late Cretaceous, and that the highest pCO _2 was achieved between the Cenomanian and the Turonian. This pCO _2 trend is in agreement with the paleotemperature records. Our results also show that three intervals of low pCO _2 (<400ppmV) in the Early and the Late Cretaceous seem to be associated with climatic changes suggestive of glacial episodes. These results suggest that the Cretaceous climatic change was associated with pCO _2 variations. Variations in the rate of outgassing caused by variations of oceanic crust production rate have been known as a major cause of the mid-Cretaceous warmth. However, our results show the discrepancy in the timing between the highest rate of oceanic crust production and the highest pCO _2 levels during the mid-Cretaceous. We interpret that large subaerial volcanisms in the Caribbean and Madagascar Large Igneous Provinces were instrumental for providing additional CO _2 to the atmosphere, resulting in the warmest mid-Cretaceous.
NSTL
Elsevier
