Along-strike forearc and subducted upper slab structure beneath north Chile: Slow slip implications
Por:
Mukherjee P., Ito Y., Borah K., Mpuang A.P., Garcia E.S., Plata-Martinez R.
Publicada:
1 ene 2024
Resumen:
We evaluate the lateral variation of the lithospheric structure beneath the forearc of the North Chile subduction zone along strike, extending from Iquique to Valparaiso, to understand a possible seismic structure that hosts deep slow earthquakes by comparing the deep slow slip areas around 60 km depth, using receiver function and inversion method. Relative differences are investigated in seismic velocities around the plate interface, especially underlying the mantle wedge, the upper part of the subducted oceanic crust, and the oceanic mantle along the subduction strike. We estimate and compare the thickness and velocity of subducted oceanic crust, slab top, subducted oceanic Moho, continental Moho, and wedge mantle velocity beneath the seismic stations. The oceanic crustal thickness range from ~5 to 10 km respectively, and the oceanic Moho depth is ~40 km–~90 km. It was observed that the disparities in velocities were more pronounced near the south of the Iquique zone (18°S-25°S), with high subducting oceanic crust velocities. These discrepancies in velocities could be regarded as the presence of fluids from subducted ridges and seamounts, which might alter seismicity in the area, including slow slip. © 2024
Filiaciones:
Earth and Planetary Science Division, Kyoto University, Japan
Earth and Environmental Science Department, Ben Gurion University of the Negev, Israel
Research Center for Earthquake Prediction, Disaster Prevention Research Institute, Kyoto University, Japan
Department of Earth Sciences, Indian Institute of Science Education and Research Kolkata, India
Institute of Geophysics, Universidad Nacional Autónoma de México, Mexico
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