Convergence of tectonic reconstructions and mantle convection models for significant fluctuations in seafloor spreading
Convergence of tectonic reconstructions and mantle convection models for significant fluctuations in seafloor spreading
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DOI：
10.1016/j.epsl.2013.09.032
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发表时间：
2013-12-01
影响因子：
5.3
通讯作者：
Tackley, P. J.
中科院分区：
文献类型：
--
作者：
Coltice, N.;Seton, M.;Tackley, P. J.
经过50年的数据收集和运动学重建工作，板块模型为过去200 My的板块运动和海底扩张提供了替代方案。然而，这些努力自然受到非常古老的海底保存不完整的限制，因此，新海底生产的时间依赖性是有争议的。在过去的200年里，它有多大的变化，以及它如何在更长的时间尺度上波动，没有共识。我们探索海底扩张和大陆漂移如何使用独立衍生的模型在漫长的地质时期内演变：最近开发的地球动力学建模方法和最先进的板块重建。运动学重建和地球动力学模型都集中于威尔逊旋回期间新海底生产率的2倍变化，同时在矩形、三角形和倾斜分布的端元之间海底面积年龄分布形状也随之发生变化。对流模型表明，在较长的时期内（类似于1戈伊）的显着波动应该存在，涉及脊长度和全球构造重组的变化。虽然是独立的，但对流模型和运动学重建都表明，海脊长度的变化至少是随着时间推移驱动海底面积年龄分布变化的重要扩展率波动。(C)2013作者Elsevier B.V.出版，保留所有权利。
For 50 years of data collection and kinematic reconstruction efforts, plate models have provided alternative scenarios for plate motions and seafloor spreading for the past 200 My. However, these efforts are naturally limited by the incomplete preservation of very old seafloor, and therefore the time-dependence of the production of new seafloor is controversial. There is no consensus on how much it has varied in the past 200 My, and how it could have fluctuated over longer timescales. We explore how seafloor spreading and continental drift, evolve over long geological periods using independently derived models: a recently developed geodynamic modelling approach and state-of-the-art plate reconstructions. Both kinematic reconstructions and geodynamic models converge on variations by a factor of 2 in the rate of production of new seafloor over a Wilson cycle, with concomitant changes of the shape of the area-age distribution of the seafloor between end members of rectangular, triangular and skewed distributions. Convection models show that significant fluctuations over longer periods (similar to 1 Gy) should exist, involving changes in ridge length and global tectonic reorganisations. Although independent, both convection models and kinematic reconstructions suggest that changes in ridge length are at least as significant spreading rate fluctuations in driving changes in the seafloor area-age distribution through time. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.