TY - JOUR
T1 - Age of the Subducting Philippine Sea Slab and Mechanism of Low-Frequency Earthquakes
AU - Hua, Yuanyuan
AU - Zhao, Dapeng
AU - Xu, Yixian
AU - Liu, Xin
N1 - Funding Information:
The hypocentral parameters of the low-frequency microearthquakes are taken from the JMA Unified Earthquake Catalog (http://www.jma.go.jp). We thank Prof. R. Müller for sharing their age data of ancient seafloor. We appreciate the helpful discussions with Haibo Wang, Tao Gou, and Yaqian Liu. The free software GMT (Wessel & Smith, 1998) is used to plot the figures. This work was partially supported by a research grant (26106005) from MEXT to D. Zhao and a grant from the NSFC (41530319) to Y. Xu. We are very grateful to Prof. Jeroen Ritsema (the Editor) and three anonymous reviewers for their thoughtful review comments that have improved this paper. The age data can be obtained by contacting Y. Hua.
Publisher Copyright:
©2018. American Geophysical Union. All Rights Reserved.
PY - 2018/3/16
Y1 - 2018/3/16
N2 - Nonvolcanic low-frequency earthquakes (LFEs) usually occur in young and warm subduction zones under condition of near-lithostatic pore fluid pressure. However, the relation between the LFEs and the subducting slab age has never been documented so far. Here we estimate the lithospheric age of the subducting Philippine Sea (PHS) slab beneath the Nankai arc by linking seismic tomography and a plate reconstruction model. Our results show that the LFEs in SW Japan take place in young parts (~17–26 Myr) of the PHS slab. However, no LFE occurs beneath the Kii channel where the PHS slab is very young (~15 Myr) and thin (~29 km), forming an LFE gap there. According to the present results and previous works, we think that the LFE gap at the Kii channel is caused by joint effects of several factors, including the youngest slab age, high temperature, low fluid content, high permeability of the overlying plate, a slab tear, and hot upwelling flow below the PHS slab.
AB - Nonvolcanic low-frequency earthquakes (LFEs) usually occur in young and warm subduction zones under condition of near-lithostatic pore fluid pressure. However, the relation between the LFEs and the subducting slab age has never been documented so far. Here we estimate the lithospheric age of the subducting Philippine Sea (PHS) slab beneath the Nankai arc by linking seismic tomography and a plate reconstruction model. Our results show that the LFEs in SW Japan take place in young parts (~17–26 Myr) of the PHS slab. However, no LFE occurs beneath the Kii channel where the PHS slab is very young (~15 Myr) and thin (~29 km), forming an LFE gap there. According to the present results and previous works, we think that the LFE gap at the Kii channel is caused by joint effects of several factors, including the youngest slab age, high temperature, low fluid content, high permeability of the overlying plate, a slab tear, and hot upwelling flow below the PHS slab.
KW - Philippine Sea slab
KW - low-frequency earthquakes
KW - slab age
KW - southwest Japan
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U2 - 10.1002/2017GL076531
DO - 10.1002/2017GL076531
M3 - Article
AN - SCOPUS:85044254101
SN - 0094-8276
VL - 45
SP - 2303
EP - 2310
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 5
ER -