气候变化领域集成服务门户(CCPortal): Global Trends of Axial Relief and Faulting at Plate Spreading Centers Imply Discrete Magmatic Events

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DOI	10.1029/2020JB019465
	Global Trends of Axial Relief and Faulting at Plate Spreading Centers Imply Discrete Magmatic Events
	Liu Z.; Buck W.R.
发表日期	2020
ISSN	21699313
卷号	125 期号:8
英文摘要	Observed variations in across-axis topographic relief and faulting style at spreading centers have been challenging to explain. Axial highs are seen at fast-spreading centers, while valleys occur for slow-spreading centers. Fault offsets range from tens of meters at fast-spreading ridges to tens of kilometers at some slow-spreading ridges. Models that fit the axial relief fail to produce observed fault patterns, while models that fit the fault patterns fail to produce observed variations in axial relief. A recent mechanical analysis (Liu & Buck, 2018, https://doi.org/10.1016/j.epsl.2018.03.045) suggests that including the effect of many discrete diking events can result in a gradual change in axial relief with crustal thicknesses. To compare this mechanical model directly with observations requires us to couple it with a two-dimensional thermal model. This allows us to estimate the axial lithospheric thickness consistently as a function of the spreading rate and crustal thickness. For thinner axial lithosphere the model predicts an axial high with relief supported by low-density material beneath the axial lithosphere. For axial lithospheric thickness between approximately one half and approximately three fourths of the crustal thickness, the axial depth decreases with magma supply increase. For thicker axial lithosphere the axial valley relief is controlled by axial brittle lithospheric thickness and near-axis lithospheric geometry. We compared model predictions to data by compiling observations on axial relief and faulting mode for all spreading centers where seismic crustal thickness has been measured. Good fit to the data is obtained for model parameters giving dike widths in the axial lithosphere close to a meter. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	axial relief; diking; faulting; spreading centers
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187735
作者单位	Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; Key Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, Beijing, China; MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
推荐引用方式 GB/T 7714	Liu Z.,Buck W.R.. Global Trends of Axial Relief and Faulting at Plate Spreading Centers Imply Discrete Magmatic Events[J],2020,125(8).
APA	Liu Z.,&Buck W.R..(2020).Global Trends of Axial Relief and Faulting at Plate Spreading Centers Imply Discrete Magmatic Events.Journal of Geophysical Research: Solid Earth,125(8).
MLA	Liu Z.,et al."Global Trends of Axial Relief and Faulting at Plate Spreading Centers Imply Discrete Magmatic Events".Journal of Geophysical Research: Solid Earth 125.8(2020).