期刊
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
卷 123, 期 9, 页码 7824-7849出版社
AMER GEOPHYSICAL UNION
DOI: 10.1029/2017JB015346
关键词
seismology; crust and uppermost mantle; ambient noise tomography; Antarctica; Transantarctic Mountains; Gamburtsev Mountains
资金
- National Science Foundation [PLR-1246712, PLR-1142518, PLR 1246151, PLR-1246416, PLR 1744883]
- IRIS DMS [EAR-1063471]
- Directorate For Geosciences
- Office of Polar Programs (OPP) [1141916, 1142126] Funding Source: National Science Foundation
- Office of Polar Programs (OPP)
- Directorate For Geosciences [1246666, 1249513] Funding Source: National Science Foundation
We construct a new seismic model for central and West Antarctica by jointly inverting Rayleigh wave phase and group velocities along with P wave receiver functions. Ambient noise tomography exploiting data from more than 200 seismic stations deployed over the past 18years is used to construct Rayleigh wave phase and group velocity dispersion maps. Comparison between the ambient noise phase velocity maps with those constructed using teleseismic earthquakes confirms the accuracy of both results. These maps, together with P receiver function waveforms, are used to construct a new 3-D shear velocity (Vs) model for the crust and uppermost mantle using a Bayesian Monte Carlo algorithm. The new 3-D seismic model shows the dichotomy of the tectonically active West Antarctica (WANT) and the stable and ancient East Antarctica (EANT). In WANT, the model exhibits a slow uppermost mantle along the Transantarctic Mountains (TAMs) front, interpreted as the thermal effect from Cenozoic rifting. Beneath the southern TAMs, the slow uppermost mantle extends horizontally beneath the traditionally recognized EANT, hypothesized to be associated with lithospheric delamination. Thin crust and lithosphere observed along the Amundsen Sea coast and extending into the interior suggest involvement of these areas in Cenozoic rifting. EANT, with its relatively thick and cold crust and lithosphere marked by high Vs, displays a slower Vs anomaly beneath the Gamburtsev Subglacial Mountains in the uppermost mantle, which we hypothesize may be the signature of a compositionally anomalous body, perhaps remnant from a continental collision.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据