Seismicity in the subducted Cocos plate below central Mexico, defined by moderate and large earthquakes, ceases well before reaching the active volcanic front. No intraslab earthquake has been reliably located below Nevado de Toluca and Popocatepetl volcanos. Here we report on an Mw3.3 event at a depth of 98 km, 38 km to the west of Nevado de Toluca. The event provides evidence, for the first time from an earthquake, of subducted slab at a depth of ~ 100 km below the volcano. Recordings of the event also provide evidence of high attenuation of shear waves as they propagate through the mantle-wedge asthenosphere. It is possible that intraslab seismicity beneath active volcanoes in central Mexico at M ~3 level is abundant but has not been documented in the past because of poor instrumentation.
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机译：在墨西哥中部下方的底层古科斯板中的地震性，由中等和大地震定义，在到达活性火山前面之前停止。没有intraslab地震已经可靠地位于Nevado de Toluca和Popocatepetl火山下方。在这里，我们举报了MW3.3的赛事，深度为98公里，距Nevado de Toluca以西38公里。该事件提供了证据，这是第一次从地震，在火山下方〜100km的深度。该事件的录音还提供了通过Mantle-Wedge浮动的剪力波衰减的证据。在M〜3级中央墨西哥中，墨西哥中央火山下的intrAlab地震性是丰富的，但由于仪器差，过去尚未记录。
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