PDF Earth Science Lecture: Volcanic Hazards

PROJECT: P – TER (PRODUCTIVITY – TARGETED EXTENSIVE REVIEW) | GRADE 12 | LECTURE HANDOUT SENIOR HIGHSCHOOL | AUF-IS AUF HONOR CODE On my honor as an Angelenean, who lives by the core values of Mabuti, Magaling at May Malasakit sa Kapwa, I hereb...

PROJECT: P – TER (PRODUCTIVITY – TARGETED EXTENSIVE REVIEW) | GRADE 12 | LECTURE HANDOUT SENIOR HIGHSCHOOL | AUF-IS AUF HONOR CODE On my honor as an Angelenean, who lives by the core values of Mabuti, Magaling at May Malasakit sa Kapwa, I hereby pledge honesty and integrity in all my academic tasks without receiving or giving unauthorized assistance, thereby observing scholarly and intellectual standards, rules on proper citation of sources, and appropriate collection and use of data. So help me God. REMINDER This lecture is written for the purpose of guiding Angeleneans as they prepare for any upcoming activity, quiz, or examination. We still highly advise everyone to look up and review as well the sources provided by the school and the teachers to prepare better on any said assessments. Break a leg! :) AUTHOR(S): (TAMAYO, BRYLE), // TEMPLATE BY: SHS Council and BOGNOT, P.N. 1 PROJECT: P – TER (PRODUCTIVITY – TARGETED EXTENSIVE REVIEW) | GRADE 12 | LECTURE HANDOUT SENIOR HIGHSCHOOL | AUF-IS EARTH SCIENCE WITH DRRR VOLCANIC HAZARDS E. Volcanic Gases OUTLINE ​ variety of gases released before and even after I.​ Volcanic-Related Hazards eruption. II.​ Signs of an Impending Volcanic Eruption ​ Water vapor - colorless, odorless, and harmless; III.​ Interpretation of Volcanic-Related Hazard Maps IV.​ Before, During, After an Eruption most abundant. ​ Carbon Dioxide - colorless and odorless; may cause unconsciousness and death in exceeding 15% I. VOLCANIC-RELATED HAZARDS concentration. ​ Lahar ​ Sulfur Dioxide - colorless with pungent odor; ​ Ashfall irritant; may create smog. ​ Pyroclastic Flow ​ Hydrogen Sulfide - colorless, flammable gas with ​ Ballistic Projectile strong offensive odor. ​ Volcanic Gas ​ Hydrogen Halides - toxic acids that quickly ​ Lava flow dissolve in the atmosphere becoming components of acid rain; poisonous A. Lahar ​ Of Indonesian origin for “Lava or lava flow”. F. Lava Flows ​ wet cement-like mixture of volcanic material and ​ rivers of incandescent molten rocks flowing down water. a slope from an eruption vent. ​ acquires older volcanic materials along rivers and ​ Low Silica Magma - low viscosity lava flow; other water channels. movement at high speeds. ​ highly mobile. ​ High Silica Magma - high viscosity lava flow; ​ may manifest in form of large boulders. movement at low speeds. ​ intense rainfall may also bring about the formation of lahar. II. SIGNS OF AN IMPENDING VOLCANIC ERUPTION B. Ashfalls ​ The frequency and intensity of earthquakes felt ​ also called “tephra falls” within the area increase. ​ Ashfall - consists of fragmented volcanic particles ​ The release of steam and gases from the vents less than 2mm in diameter in size near the volcano increases. ​ Tephra - fragmented volcanic particles in general ​ Fumarolic activity increases C. Pyroclastic Flows ​ Heat emission increases ​ Pyroclastic Flow - dense type of current that moves ​ Visible ground elevation and ground fissuring. slower than surge. ​ Flowing lava with red-orange colors is visible at ​ Pyroclastic Surge - diluted type of current that has the mouth of the volcano. more mobility. ​ Landslides. ​ Pyroclastic Density Currents (PDC) - materials ​ Springs of bodies of water within the area are released from the mouth of the volcano after its drying up. explosion. D. Ballistic Projectiles III. INTERPRETATION OF VOLCANIC-HAZARD MAPS ​ may be likened to a cannonball usually landing 2- 5 A. Hazard Maps km away from the vent. ​ serve as a guide to people about the danger zones ​ Bombs - derived from fresh magma; attain and safe zones in the vicinity of the volcano. smoothness and peculiar shapes before they fall. ​ the basis of the country’s risk of volcanic eruption is ​ Blocks – chips off the walls of the volcanic vent; based on the activity of these volcanoes and rough with sharp edges. population density. AUTHOR(S): (TAMAYO, BRYLE), // TEMPLATE BY: SHS Council and BOGNOT, P.N. 2 PROJECT: P – TER (PRODUCTIVITY – TARGETED EXTENSIVE REVIEW) | GRADE 12 | LECTURE HANDOUT SENIOR HIGHSCHOOL | AUF-IS Mayon Volcano Lava Flow Hazard Map ​ Fireproof house premises from passing lava flows and hot falling fragments by clearing flammable objects. ​ Participate in community efforts to prevent or mitigate the effects of volcanic hazards. B. During the Eruption ​ Those within danger zones should evacuate carefully and orderly with their family to designated evacuation centers. ​ Once inside the evacuation centers, stay there. Mayon Volcano Pyroclastic Flow Hazard Map ​ Keep doors and windows closed to minimize ash exposure. ​ Be ready to use gas mask to protect eyes and respiratory system from ash. ​ Be alert for advisories regarding the status of volcanic activity and for possible re-evacuation to safer evacuation sites. C. After the Eruption ​ Stay where you are and do not attempt to go back to the danger zones unless advised by competent authorities that the crisis is over and that it is safe to Mayon Volcano Ash Fall Hazard Map go back. ​ As a precaution, allow only adults and responsible members of the community to check on the livability and safety of the areas affected before going back. ​ Proceed to one’s respective area with caution. ​ Participate in community efforts to ensure the availability of safe food, decent shelter, clean water, sanitation facilities, medicine, and other evacuation center necessities for yourself, your family, and all evacuees. ​ Assist in maintaining peace and order and Mayon Volcano Lahar Hazard Map cleanliness within the evacuation center. The following information on this handout is referred from the recommended references and textbooks. Please review them as well. Thank you and Goodluck! IV. BEFORE, DURING, AFTER AN ERUPTION A. Before the Eruption ​ Always monitor the status of volcanic activity. Be prepared to evacuate whenever a warning is issued that requires leaving the danger zones ​ Prepare a family evacuation plan which should be consistent with that of the community. ​ Make provisions for transportation and communication. Prepare food and water supplies, medicines, and survival kits that you can bring when the need for evacuation arises. ​ Review materials and listen to advisories regarding the primary volcanic hazards such as earthquakes, tsunamis, and flooding that may not be emphasized AUTHOR(S): (TAMAYO, BRYLE), // TEMPLATE BY: SHS Council and BOGNOT, P.N. 3