Upper mantle tomography in the northwestern Pacific region using triplicated P waves

作者：Takeuchi Nozomu^*; Kawakatsu Hitoshi; Tanaka Satoru; Obayashi Masayuki; Chen Y John; Ning Jieyuan; Grand Steve P; Niu Fenglin; Ni James; Iritani Rryohei; Idehara Koki; Tonegawa Takashi

来源：JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 2014, 119(10): 7667-7685.

DOI：10.1002/2014JB011161

• tomography
• triplication
• subduction zones
• off-arc volcanoes

We conducted delay time tomography of the upper mantle beneath the northwestern Pacific using P data from NorthEast China Extended SeiSmic Array, F-net, and nearby available stations. To improve resolution and accuracy in the vicinity of mantle discontinuities, we extracted traveltimes of both initial and secondary phases observed at triplication distances by using a waveform fitting technique. Compared with the model obtained by using only the initial phase, the resolution just above the 410 km discontinuity is especially improved, and low-velocity anomalies beneath the Changbai Volcano are clearly observed down to the 410 km discontinuity. Compared with previous models, low-velocity anomalies atop the 410 are more pronounced. The results of this study together with the previous receiver function analysis provide further support that we have hot material beneath the Changbai Volcano. %26lt;br%26gt;Key Points%26lt;list list-type=%26quot;bulleted%26quot;%26gt;%26lt;list-item id=%26quot;jgrb50846-li-0001%26quot;%26gt;We developed a new method for delay time tomography of triplicated P waves%26lt;list-item id=%26quot;jgrb50846-li-0002%26quot;%26gt;The method improved resolution in the vicinity of mantle discontinuities%26lt;list-item id=%26quot;jgrb50846-li-0003%26quot;%26gt;The results provide support for hot material beneath the Changbai Volcano

• 出版日期2014-10
• 单位北京大学