Large igneous provinces and organic carbon burial: Controls on global temperature and continental weathering during the Early Cretaceous
Large igneous provinces and organic carbon burial: Controls on global temperature and continental weathering during the Early Cretaceous
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DOI：
10.1016/j.gloplacha.2015.09.001
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发表时间：
2015-10-01
影响因子：
3.9
通讯作者：
Mutterlose, Joerg
中科院分区：
文献类型：
--
作者：
Bodin, Stephane;Meissner, Philipp;Mutterlose, Joerg
有大量的证据表明，早白垩世期间存在短时间的寒冷气候条件。然而，缺乏高分辨率，长期的早白垩世古温度记录阻碍了这些假定的“寒流”事件的全面综合，以及更全面的方法来研究早白垩世的气候变化。我们提出了一个扩展的汇编，涵盖Berriasian-middle Albian从Vocontian盆地（法国东南部）的氧，碳和锶同位素记录的铍石。该数据集清楚地表明了早白垩世期间三个寒冷气候条件的时间段（晚Valanginian-最早Hauterivian，晚早Aptian，最晚Aptian-最早Albian）。这些间隔都与快速和高幅度的海平面波动，支持在早白垩世极地冰盖的短暂增长的假设。正碳同位素漂移证明，每一个冷事件与全球范围内的有机质埋藏增强。此外，在大火成岩省喷发的时间和规模与早白垩世变暖事件的幅度之间有一个相对较好的匹配。总之，这些观测结果证实了大气CO2变化在驱动早白垩世气候变化中的作用。从长期的角度来看，全球古温度和海水锶同位素比值在早白垩世的耦合是最好的解释温度控制的大陆地壳风化率的变化。(C)2015爱思唯尔B. V.保留所有权利。
There is an abundance of evidence for short intervals of cold climatic conditions during the Early Cretaceous. However, the lack of a high-resolution, long-term Early Cretaceous paleotemperature record hampers a fullscale synthesis of these putative "cold snap" episodes, as well as a more holistic approach to Early Cretaceous climate changes. We present an extended compilation of belemnite-based oxygen, carbon and strontium isotope records covering the Berriasian-middle Albian from the Vocontian Basin (SE France). This dataset clearly demonstrates three intervals of cold climatic conditions during the Early Cretaceous (late Valanginian-earliest Hauterivian, late early Aptian, latest Aptian-earliest Albian). Each of these intervals is associated with rapid and high amplitude sea-level fluctuations, supporting the hypothesis of transient growth of polar ice caps during the Early Cretaceous. As evidenced by positive carbon isotope excursions, each cold episode is associated with enhanced burial of organic matter on a global scale. Moreover, there is a relatively good match between the timing and size of large igneous province eruptions and the amplitude of Early Cretaceous warming episodes. Altogether, these observations confirm the instrumental role of atmospheric CO2 variations in driving Early Cretaceous climate change. From a long-term perspective, the coupling of global paleotemperature and seawater strontium isotopic ratio during the Early Cretaceous is best explained by temperature-controlled changes of continental crust weathering rates. (C) 2015 Elsevier B.V. All rights reserved.