Thermal structure of the subduction zone in western Japan derived from seismic attenuation data

• Published in: Geophysical research letters Vol. 37; no. 6; pp. np - n/a
• Main Authors: Nugraha, Andri Dian, Mori, Jim, Ohmi, Shiro
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 01.03.2010; John Wiley & Sons, Inc
• Subjects: Attenuation; Earthquakes; Geophysics; Plate tectonics; Seismic phenomena; Seismology; Slabs; Stations; temperature; Temperature distribution; Three dimensional models; tomography; Japan
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2009GL041522

We use a well determined three‐dimensional attenuation model to infer the temperature distribution of the subduction zone in western Japan. The tomographic attenuation model was derived from about 19,000 t* determinations for P‐ waves recorded at 128 stations. The attenuation model with a previously determined velocity model was used to infer the temperature distribution of the subduction zone from depths of 15 to 80 km, using the high temperature background method. We can clearly see the cooler slab (400°C to 700°C) that is being subducted under the hotter mantle material (425°C to 850°C). We also show that the deep low‐frequency earthquakes are occurring in regions just above the slab with temperatures of about 500°C to 600°C.