Ahyi volcano (Mariana Islands, USA) - Smithsonian / USGS Weekly Volcanic Activity Report for 7 May-13 May 2014 (New Activity / Unrest)

Seismic stations on Pagan, Sarigan, Anatahan, and Saipan started recording signals on 24 April that continued at least through 2 May. The source had not been confirmed, but is thought to be at or near the Ahyi seamount. During 4-5 May a helicorder plot from a station on Pagan showed explosive signals at a rate of 20 per hour. ... Read all

USGS raised the alert level for the submarine volcano due to abnormal seismicity detected in the area by hydroacoustic devices and land-based network devices on neighboring islands. ... Read all

Seismic stations on Pagan, Sarigan, Anatahan, and Saipan began recording signals starting at 0635 on 24 April believed to be from an undersea volcanic source. Hydroacoustic sensors on Wake Island suggested that the source is at or near Ahyi seamount, although it was possible that the vent is located at one of the other volcanic seamounts in the area. While conducting coral reef research at Farallon de Pajaros, NOAA divers reported hearing loud explosions and feeling the shock waves. ... Read all