Potential Volcano-Related Hazards PDF

Potential Volcano- Related Hazards  Signs of Impending Volcanic Eruption OBJECTIVES: Appreciate Explain the the most Identify the Recognize...

Potential Volcano- Related Hazards  Signs of Impending Volcanic Eruption OBJECTIVES: Appreciate Explain the the most Identify the Recognize importance common different the signs of of being volcano- parameters impending prepared related used to volcanic especially hazards in monitor eruptions. during the the volcanoes. occurrence of Philippines. a disaster. What is Volcanic hazards? What is Volcanic eruption? This Photo by Unknown Author is licensed under CC BY According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS)the following are commonly observed signs that a volcano is about to erupt. These precursors may vary from volcano to volcano 1.Increase in the frequency of volcanic quakes with rumbling sounds; occurrence of volcanic tremor 2. Increased steaming activity; change in color of steam from white to gray due to entrained ash 3.Crater glow due to presence of magma at or near the crater 4.Ground swells (or inflation), ground tilt and ground fissuring due to magma intrusion 5. Localized landslides, rock falls and landslides from the summit area are not attributed to heavy rains 6. Noticeable increase in drying up of vegetation around the volcano's upper slopes 7. Increase in temperature of hot springs, wells and crater lake 8. Noticeable variation in the chemical content of springs, crater lakes within the vicinity of the volcano 9. Drying up of springs/wells around the volcano 10. Development of new thermal areas(an area of muddy hot springs) and/or reactivation of old ones; appearance of solfataras (craters with sulfur gas According to Oregon State University Volcanologists use many different kinds of tools including instruments that detect and record earthquakes (seismometers and seimographs), instruments that measure ground deformation (EDM, Leveling, GPS, tilt), instruments that detect and measure volcanic gases (COSPEC), instruments that determine how much lava is moving underground (VLF, EM-31), video and still cameras, infrared cameras, satellite imagers, webcams, and others instruments that detect and record earthquakes (seismometers and seimographs) COSPEC-Correlation Spectrometer measure volcanic gases instruments that measure ground deformation EM-31 instruments that determine how much lava is moving underground  The parameters used to monitor volcanoes are: 1. Ground deformation – any surface changes on a volcano (subsidence/sinking, tilting, bulging); often use of satellite imaging which results to less exposure on the ground or safer for volcanologists. However, interpretation needs field verification sometimes. 2. Seismic Activity – When magma rises up, it breaks rock along the way. Thus, earthquakes are generated. Monitoring of quakes/tremors is done by using a seismometer that determines which patterns of seismic waves precede an eruption.  by people living near volcano) Visual – intensified presence of steam; drying up of vegetation,wells/spring/lake; crater glow at the mouth of the volcano Auditory – Rumbling sounds are heard. Olfactory – observed foul smell (usually rotten egg caused by sulfur) caused by presence of volcanic gases Tactile – ground movement/earthquake is felt Thank you everyone! God bless us all