Thursday 9 April 2020

Volcanos

Roundup of Global Volcanic Activity – New Activity for the Week 1 April 2020 – 7 April 2020

Kerinci | Indonesia : PVMBG reported that at 0854 on 6 April a brown ash emission rose 500 m above Kerinci’s summit and drifted NNW. Another brown emission was visible the next day at 0717, rising at least 400 m and drifting ENE. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Piton de la Fournaise | Reunion Island (France) : OVPF reported that a seismic crisis at Piton de la Fournaise was recorded during 0815-0851 on 2 April and was accompanied by rapid deformation (10-20 microradians). After a lull in activity for about three hours, volcanic tremor beginning at 1220 indicated the likely arrival of magma at the surface, though weather conditions prevented visual confirmation. During an overflight that day around 1500 observers confirmed a fissure eruption around 1,900 m elevation on the E flank about 1.7 km from the center of Dolomieu Crater, and just below the 10-16 February eruption site. Lava fountains rose no more than 30 m. By 0625 on 3 April lava flows had traveled as far as the top of Grandes Pentes, at 1,000 m elevation and 3.8 km from RN2 (the national road). By 1500 no significant deformation had been recorded and five volcano-tectonic earthquakes were located less than 2 km deep. The report noted that the weak seismicity and minor deformation indicated that the magma followed an existing pathway while propagating towards the surface. The average lava-flow rate during 3-4 April was between 2 and 45 cubic meters per second with an average around 7-10 cubic meters per second. Lava flows continued to advance, reaching 800 m elevation. During 0400-0900 on 5 April the seismic network recorded 10 volcano-tectonic earthquakes (less than 2 km deep) prompting a request for an overflight and an inspection of the flow field. The distal end of the lava flow was located at 550 m elevation, about 2.7 km from RN2. The lava-flow rate had increased to between 3 and 63 cubic meters per second with an average around 24.2 cubic meters per second on 5 April and increased again to an estimate average of 30 cubic meters per second on 6 April. The longest flow had stopped advancing with activity focused on a new, more southern lava flow. By 1000 on 6 April the southern lava flow had descended to 360 m elevation, or about 2 km from RN2, as mapped during an overflight. Large quantities of Pele’s hair were located in areas to the N, especially in La Plaine des Cafres. A sharp decrease in tremor intensity was recorded around 1330 on 6 April, signaling the end of the eruption.

Semeru | Eastern Java (Indonesia) : PVMBG reported that during 30 March-5 April white plumes rose 100 m above Semeru’s summit. Incandescent material was ejected 10-50 m above the Jonggring-Seloko Crater. Incandescent material from the ends of lava flows descended 700 m, reaching a maximum distance of 950 m from the crater. The Alert Level remained at 2 (on a scale of 1-4), and the public was reminded to stay outside of the general 1-km radius from the summit and 4 km on the SSE flank.

Soputan | Sulawesi (Indonesia) : The Darwin VAAC reported that on 2 April an ash plume from Soputan was seen by a pilot drifting W at an altitude of 4.3 km (14,000 ft) a.s.l.



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