02/05/2015. Calbuco , Bulusan , Yellowstone.
Calbuco, Chili :
After the onset of eruptive pulse yesterday, seismic activity has evolved into a continuous energy tremor signal higher than that recorded hours before the eruption, which shows that the volcanic system is in a phase of sustained excitement.
In the last 24 hours seismic activity associated with the movement of fluids inside the volcano showed a progressive decrease in the energy corresponding to the post eruptive pulse which took place at 13:08 (GMT 4:08 p.m. ), after which the seismicity has stabilized, although the amplitude of the tremor continues without returning to the level it had before the pulse. During this period, the amplitude of tremor signal presented the dominant frequencies between 0.5 to 2.5 Hz and reduced displacement values [DR, parameter indicating the size of the seismic signal at source] under 16, 8 cm2, values considered as moderate.
Similarly, it was recorded twenty-eight (28) long period (LP) events, with local magnitudes ML equal and below M1,5 and reduced displacement (DR) of less than 29.8 cm2, values considered as moderate. Regarding the type of seismicity VT [associated with the fracturing of rock], thirty-eight (38) earthquakes were recorded, with the greatest energy from a local earthquake [ML] 1.5 located 6.1 km to the west-northwest (ONW) of the crater, at a depth of 9.4 km.
Source : Sernageomin
Photos : AP / EPA, dailymail.co.uk.
Bulusan , Philippines :
Update May 2, 2015 8:30.
This is an update on the steam and ash explosion of Bulusan Volcano in Sorsogon (12.7667°N, 124.0500°E) at 8:09 AM yesterday (May 1, 2015), which lasted 5 minutes based on seismic records. The explosion distributed traces of ash in the areas west and west-northwest of the volcano affecting the barangays of Bolos, Cogon, Gulang-Gulang, Sangkayon, Tinampo, and Umagom in Irosin, Sorsogon and barangay Puting Sapa in Juban, Sorsogon. The Bulusan Volcano seismic network recorded a total of sixty-two (62) volcanic earthquakes in the next 8 hours after the explosion but no volcanic earthquakes were recorded afterwards. The earthquakes were likely caused by the response and readjustments of the edifice of the volcano due to the explosion.
Alert Level 0 status currently prevails over Bulusan Volcano. However the local government units and the public are reminded that entry into the 4-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited due to the possibility of sudden and hazardous steam-driven or phreatic eruptions. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ejecta from any sudden phreatic eruption can be hazardous to aircraft. Furthermore, people living within valleys and along river/stream channels should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall. DOST-PHIVOLCS is closely monitoring Bulusan Volcano’s activity and any new development will be relayed to all concerned.
Source : DOST-PHIVOLCS
Photo : Wikipedia
Yellowstone, Etats- Unis :
44 ° 25’48 “N 110 ° 40’12” W,
Summit Elevation 9203 ft (2805 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
During April 2015, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, reports 62 earthquakes were located in the Yellowstone National Park (YNP) region. The largest event was a small earthquake of magnitude 2.2 on April 26, at 10:03 PM MDT, located about 5 miles northeast of Lake, WY.
No earthquake swarm activity was present during April.
Yellowstone earthquake activity in April remains at low background levels.
GPS stations in the caldera (and north of the caldera) exhibit minimal movement either up or down at this time. An example can be found at:
http://www.unavco.org/instrumentation/networks/status/pbo/data/HVWY (click on Static Plots / Time Series)
The Yellowstone Volcano Observatory (YVO) provides long-term monitoring of volcanic and earthquake activity in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.
Source : YVO
Photo : Yellowstonepark