Isarog VulkanIsarog volcano is an andesitic stratovolcano of Naga city, in SE Luzon, Philippines. It is part of the Bicol volcanic chain, and could still be active although no historic eruptions are known. The volcano has active fumaroles, steam vents and hot springs.
Beschreibung:Isarog volcano forms the broad isthmus between Lagonoy Gulf and San Miguel Bay. The volcano is truncated by a 2.5-km-wide crater breached to the east where is drained by the narrow gorge of the Quinarag River.
1915-16 earthquakes & seismic unrest
On 8 November, 1915, frequent earthquakes were felt on and around Isarog volcano, with some occasional noises. Landslides occurred on the slopes of Isarog volcano. The seismic swarm repeated itself 2 or 3 times at long
intervals until 10 January, 1916. The volcano was thickly wooded, even inside of the crater, and nobody observed any fumaroles.
Source: "Awakening of two old volcanoes in Luzon, Philippine Idands." Bulletin of the Seismological Society of America; December 1916; v. 6; no. 4; p. 236-240