气候变化领域集成服务门户(CCPortal): Ubiquitous lower-mantle anisotropy beneath subduction zones

CCPortal

DOI	10.1038/s41561-019-0325-7
	Ubiquitous lower-mantle anisotropy beneath subduction zones
	Ferreira A.M.G.; Faccenda M.; Sturgeon W.; Chang S.-J.; Schardong L.
发表日期	2019
ISSN	17520894
英文摘要	Seismic anisotropy provides key information to map the trajectories of mantle flow and understand the evolution of our planet. While the presence of anisotropy in the uppermost mantle is well established, the existence and nature of anisotropy in the transition zone and uppermost lower mantle are still debated. Here we use three-dimensional global seismic tomography images based on a large dataset that is sensitive to this region to show the ubiquitous presence of anisotropy in the lower mantle beneath subduction zones. Whereas above the 660 km seismic discontinuity slabs are associated with fast SV anomalies up to about 3%, in the lower mantle fast SH anomalies of about 2% persist near slabs down to about 1,000–1,200 km. These observations are consistent with 3D numerical models of deformation from subducting slabs and the associated lattice-preferred orientation of bridgmanite produced in the dislocation creep regime in areas subjected to high stresses. This study provides evidence that dislocation creep may be active in the Earth’s lower mantle, providing new constraints on the debated nature of deformation in this key, but inaccessible, component of the deep Earth. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124733
作者单位	CERIS, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal; Department of Earth Sciences, Faculty of Mathematics & Physical Sciences, University College London, London, United Kingdom; Dipartimento di Geoscienze, Università di Padova, Padova, Italy; Division of Geology and Geophysics, Kangwon National University, Chuncheon, South Korea; Department of Geophysics and Planetary Sciences, Tel Aviv University, Tel Aviv, Israel
推荐引用方式 GB/T 7714	Ferreira A.M.G.,Faccenda M.,Sturgeon W.,et al. Ubiquitous lower-mantle anisotropy beneath subduction zones[J],2019.
APA	Ferreira A.M.G.,Faccenda M.,Sturgeon W.,Chang S.-J.,&Schardong L..(2019).Ubiquitous lower-mantle anisotropy beneath subduction zones.Nature Geoscience.
MLA	Ferreira A.M.G.,et al."Ubiquitous lower-mantle anisotropy beneath subduction zones".Nature Geoscience (2019).