Volcanoes: Types, Eruptions & Geothermal Energy

Identify what a volcano is Differentiate its various activity states, features, and locations Name notable volcanoes in the Philippines Analyze the effects of a volcanic eruption Understand possible energy options for volcanic activity  What is a volcano? What are the different types of volcano...

Identify what a volcano is Differentiate its various activity states, features, and locations Name notable volcanoes in the Philippines Analyze the effects of a volcanic eruption Understand possible energy options for volcanic activity  What is a volcano? What are the different types of volcanoes? Why is the Philippines riddled in volcanoes? What happens in a volcanic eruptions? How is energy harnessed near volcanically active zones?  Review Where is the Crust? Mantle? Core? Volcanoes A close look What is a Volcano? ▪ A rupture/opening in the Earth's crust. ▪ Magma beneath the Earth’s crust spews out of a volcano as lava. ▪ Along with lava, it also releases ash, rocks, and hot gases. ▪ It has distinct geological activities called eruptions.  What is a Volcano? ▪ A rupture/opening in the Earth's crust. ▪ Magma beneath the Earth’s crust spews out of a volcano as lava. ▪ Along with lava, it also releases ash, rocks, and hot gases. ▪ It has distinct geological activities called eruptions. Parts of a Volcano Lava Layer Ash Layer Parts of a Volcano Throat Internal Structure Flack Vent Conduit Magma Chamber Identify if these are considered volcanoes: Differences Based on Activity 1. Active Volcano ▪ Has erupted at least within the last 10,000 years. ▪ Shows volcanic activity in the form of volcanic quakes and/or frequent gas emissions. 2. Inactive or Dormant Volcano ▪ Hasn’t erupted when it is expected to erupt. ▪ Shows a bit of geological activity. Differences Based on Activity 3. Extinct Volcano ▪ Hasn’t shown any sign of geological activity whatsoever. Lack of eruption probably due to having no more lava supply. ▪ Can become active once more in rare cases. Differences Based on Features 1. Composite Volcano ▪ Also known as stratovolcano. Most common type of volcano. ▪ Characterized by the crater raised above a mountainous land mass. ▪ Magma usually composed of silica (similar to sand/broken bits of glass) Differences Based on Features 2. Shield Volcano ▪ Characterized by the crater on top of a relatively broad and flat land mass. ▪ Magma contains less silica. Lava pouring out of it reaches farther distances at a significantly faster rate due to its shape. Differences Based on Features 3. Cinder Cone Volcano ▪ Also known as pyroclastic cones. They are the simplest type of volcano. ▪ Its body is primarily made up of cooled pyroclastic material from previous eruptions (imagine the lava as the cement of the volcano’s body). ▪ Lava released during eruption dries and becomes rock fragments called cinders. These then line the entirety of the volcano slowly shaping the body of the volcano into an oval shape. Differences Based on Location 1. Continental Volcano 2. Submarine Volcano ▪ Found on land. ▪ Found on the ocean floor. ▪ Unlike its land counterpart, it showcases a diverse ecosystem of chemotrophs (organisms that make food from inorganic elements) and thermophiles (organisms that live in very hot conditions). Differences Based on Location 3. Subglacial Volcano ▪ Found underneath glaciers in either land or seafloor. ▪ When highly active, can cause massive floods in the area called jökulhlaups. These floods are from melted glacial sheets surrounding the volcano. Identify the Following Volcanoes here in the Philippines Identify the Following Volcanoes here in the Philippines Mt. Kanlaon  Identify the Following Volcanoes here in the Philippines Taal Volcano Identify the Following Volcanoes here in the Philippines Mt. Pinatubo  Identify the Following Volcanoes here in the Philippines Mt. Bulusan Identify the Following Volcanoes here in the Philippines Mayon Volcano Why Are There Many Volcanoes in the Philippines? ▪ The Philippines has hundreds of volcanoes, with around 53 of them being active. ▪ The Philippines is a part of the Pacific Ring of Fire, a large area in the rim of the Pacific ocean where volcanic and tectonic activity is high and common. ▪ Because of these, part of the innovations and technologies needed by our country are volcano eruption and earthquake early detection devices. Due to the nature of both phenomenon being unpredictable, we always must be ready.  OF THE DAY Remember: #CharlieSpencerChaplin C – omposite volcano S – hield volcano C – inder cone volcano Global-Local Issues ▪ Volcanoes are indeed one of nature’s most terrifying yet beautiful features. They are a reminder to us that each event in this world affects all things, living or nonliving. Like how we can appreciate an uncontrollable force of nature, how can YOU appreciate the things in your life that you cannot control? How can you add beauty and meaning to something that might seem unpleasant? Volcanic Eruption  What is an ERUPTION? ▪ Characterized by the discharge of lava out of the mouth of the volcano. Usually accompanied by large amounts of smoke and ashfall. Volcanoes that have lava with low silica content is characterized as having a runny type of lava, therefore they have less violent eruptions compared to volcanoes with a high silica content. ▪ The volcano sometimes “explodes” in an eruption because of the pressure built up inside of it. Magma that cooled down from previous eruptions block the escape of the gases inside the volcano, thus producing the explosion. What is an ERUPTION? ▪ To sum up, eruptions are caused by differences in density and pressure inside the volcano. These factors cannot be manipulated by any man-made methods. ▪ As a result, eruptions cannot be accurately predicted. Geologists (people who study the Earth’s crust and its components), volcanologists (people who study volcanoes), and seismologists (people who study earthquakes) can only give warning signals from the recent geological activity inside the volcano. These warnings are based on data gathered from instruments such as seismometers and tiltmeters. Types of Eruption 1. Phreatic ▪ A stream-driven eruption as the hot rocks come in contact with water. It is short-lived, characterized by ash columns but may be an onset of a larger eruption 2. Phreatomagmatic ▪ A violent eruption due to the contact between water and magma. A large column of ash and pyroclastic emissions called base surges happen during this type of eruption Types of Eruption 3. Strombolian ▪ A weak to violent burst of an eruption best described by a spurting fountain of lava. 4. Vulcanian ▪ A tall eruption with columns reaching as high as 20 km in the sky, with devastating pyroclastic flow and ashfall. Types of Eruption 5. Plinian ▪ Characterized by an explosive release of pyroclastic material, ash, and gases. Eruption columns climb as high as 50 km in the sky ▪ Considered as the most destructive type of eruption. UN SDG #15: LIFE ON LAND ▪ Are volcanic eruptions always bad? How can eruptions be useful for the planet? ▪ Should we attempt to “stop” eruptions solely for the sake of preventing damage to nearby cities and communities? Why or why not? Hazards of a Volcanic Eruption Hazards of a Volcanic Eruption 1. Lava Flow – Most eruptions have some sort of expulsion of lava. Some have violent flow while some have slow and steady flow. Either way, anything in its path will most likely be destroyed, hence the need for a restriction zone around the crater of the volcano. Hazards of a Volcanic Eruption 2. Volcanic Earthquakes – Strong eruptions may generate earthquakes called volcanic earthquakes. Unlike tectonic earthquakes which are the result of moving plates, volcanic earthquakes are caused by the sudden release of energy during an eruption that quite literally shakes the ground. In volcanoes near lakes and seas, these quakes can displace water in a violent manner known as a volcanic tsunami. Hazards of a Volcanic Eruption 3. Tephra Fall – Commonly known as ash fall. Propelled hundreds to thousands of meters from the volcanic plume, these particulates can reach very far places, sometimes crossing other countries. Tephra accumulates in the atmosphere and falls back down to the ground, where it poses a lot of problems including water contamination, infrastructure degradation, and triggers respiratory illness or other related illnesses. Hazards of a Volcanic Eruption 4. Lahar – Known as volcanic mudflows, they are a rapid moving mixture of volcanic debris and water that travel in river valleys. Rainfall can increase a lahar’s destructive capabilities, wiping out any infrastructure near riversides. UN SDG #11: SUSTAINABLE CITIES AND COMMUNITIES ▪ Since a lot of people live near volcanoes and certain industries make use of volcanic materials / local resources near the volcano, how can we ensure the safety of these communities that live near volcanoes? ▪ Is it a good idea to not live near volcanoes? Why or why not? Our Trusty Agency for Volcano-Related Information ▪ Short for “Philippine Institute of Volcanology and Seismology”. It is under the Department of Science and Technology. ▪ Formed on September 17, 1982, they are a national institution committed to provide useful information regarding volcanic activities, that includes earthquakes, tsunamis, and other relevant information. ▪ Their main headquarters can be found at C.P. Garcia Avenue, UP Campus, Diliman, Quezon City. ▪ Visit their website to learn more about them: https://www.phivolcs.dost.gov.ph/index.php Energy from Volcanic Activity Energy from Volcanic Activity ▪ Energy can be tapped from the volcanic activities of the nearby area by means of geothermal energy. ▪ It can be harnessed via a geothermal power plant. How does a Geothermal Power Plant Work? ▪ It works by using Earth’s heat to convert water into steam, which them produces energy to power a turbine that drives an electric generator. It produces little to no traces of carbon dioxide, as compared with the conventional use of burning fossil fuel. How does a Geothermal Power Plant Work? ▪ Steam Tank – absorbs heat to boil water into steam. ▪ Steam Turbine – large turbine that rotates due to steam passing through it. How does a Geothermal Power Plant Work? ▪ Generator – converts the mechanical energy of the steam turbine into electrical energy. How does a Geothermal Power Plant Work? ▪ Steam condenser – converts excess steam back into water. ▪ Injection pump – releases excess water back into a reservoir. How does a Geothermal Power Plant Work? ▪ Cooling tower – releases excess geothermal heat from the condenser into the air as harmless heat and steam. Geothermal Power Plants in the Philippines Some of these geothermal power plants are: ▪ Tiwi Geothermal Power Plant in Tiwi, Albay ▪ Mak-Ban (Makiling-Banahaw) Geothermal Power Plant in Calauan, Laguna UN SDG #7: AFFORDABLE AND CLEAN ENERGY ▪ Can we reliably use geothermal energy for the entire country’s source of energy? Why or why not? ▪ What are the benefits of geothermal energy over our current energy production?  OF THE DAY Remember: #PapasokPoSaVahayPlease? P – hreatic P – hreatomagmatic S – trombolian V – ulcanian P – linian Global-Local Issues ▪ Most people were not expecting the effects of the ashfall caused by the 2020 Taal Volcano eruption. In addition to that, it was a bad show of greed for some Filipinos who hoarded much needed supplies like face masks. What could’ve we done different to have spared us from inflicting needless harm to our fellow Filipinos in need? What do YOU intend to do in the future?