DOI: 10.1038/ngeo2849
论文题名: Decrease in oceanic crustal thickness since the breakup of Pangaea
作者: Van Avendonk H.J.A. ; Davis J.K. ; Harding J.L. ; Lawver L.A.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2017
卷: 10, 期: 1 起始页码: 58
结束页码: 61
语种: 英语
Scopus关键词: Archean
; cooling
; crustal thickness
; deep sea
; Jurassic
; mantle
; mid-ocean ridge
; oceanic crust
; oceanic lithosphere
; paleoceanography
; Pangaea
; plate tectonics
; seismic data
; seismic refraction
; subduction
; trench
; upper mantle
; wake
; Atlantic Ocean
; Pacific Ocean
英文摘要: Earth's mantle has cooled by 6-11 °C every 100 million years since the Archaean, 2.5 billion years ago. In more recent times, the surface heat loss that led to this temperature drop may have been enhanced by plate-tectonic processes, such as continental breakup, the continuous creation of oceanic lithosphere at mid-ocean ridges and subduction at deep-sea trenches. Here we use a compilation of marine seismic refraction data from ocean basins globally to analyse changes in the thickness of oceanic crust over time. We find that oceanic crust formed in the mid-Jurassic, about 170 million years ago, is 1.7 km thicker on average than crust produced along the present-day mid-ocean ridge system. If a higher mantle temperature is the cause of thicker Jurassic ocean crust, the upper mantle may have cooled by 15-20 °C per 100 million years over this time period. The difference between this and the long-term mantle cooling rate indeed suggests that modern plate tectonics coincide with greater mantle heat loss. We also find that the increase of ocean crustal thickness with plate age is stronger in the Indian and Atlantic oceans compared with the Pacific Ocean. This observation supports the idea that upper mantle temperature in the Jurassic was higher in the wake of the fragmented supercontinent Pangaea due to the effect of continental insulation. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/105871
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: University of Texas Institute for Geophysics, Jackson School of Geosciences, Austin, TX, United States
Recommended Citation:
Van Avendonk H.J.A.,Davis J.K.,Harding J.L.,et al. Decrease in oceanic crustal thickness since the breakup of Pangaea[J]. Nature Geoscience,2017-01-01,10(1)