Dataset Information

Time-calibrated Milankovitch cycles for the late Permian.

ABSTRACT: An important innovation in the geosciences is the astronomical time scale. The astronomical time scale is based on the Milankovitch-forced stratigraphy that has been calibrated to astronomical models of paleoclimate forcing; it is defined for much of Cenozoic-Mesozoic. For the Palaeozoic era, however, astronomical forcing has not been widely explored because of lack of high-precision geochronology or astronomical modelling. Here we report Milankovitch cycles from late Permian (Lopingian) strata at Meishan and Shangsi, South China, time calibrated by recent high-precision U-Pb dating. The evidence extends empirical knowledge of Earth's astronomical parameters before 250 million years ago. Observed obliquity and precession terms support a 22-h length-of-day. The reconstructed astronomical time scale indicates a 7.793-million year duration for the Lopingian epoch, when strong 405-kyr cycles constrain astronomical modelling. This is the first significant advance in defining the Palaeozoic astronomical time scale, anchored to absolute time, bridging the Palaeozoic-Mesozoic transition.

SUBMITTER: Wu H

PROVIDER: S-EPMC3778519 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Time-calibrated Milankovitch cycles for the late Permian.

Wu Huaichun H Zhang Shihong S Hinnov Linda A LA Jiang Ganqing G Feng Qinglai Q Li Haiyan H Yang Tianshui T

Nature communications 20130101

An important innovation in the geosciences is the astronomical time scale. The astronomical time scale is based on the Milankovitch-forced stratigraphy that has been calibrated to astronomical models of paleoclimate forcing; it is defined for much of Cenozoic-Mesozoic. For the Palaeozoic era, however, astronomical forcing has not been widely explored because of lack of high-precision geochronology or astronomical modelling. Here we report Milankovitch cycles from late Permian (Lopingian) strata ...[more]

PMID: 24030138

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Dataset Information

Time-calibrated Milankovitch cycles for the late Permian.

Publications

Time-calibrated Milankovitch cycles for the late Permian.

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