This document discusses both intrusive and extrusive volcanic features. Intrusive features include dykes, sills, laccoliths, batholiths, and plugs, which form when magma penetrates underground. Extrusive features result from magma emerging at the surface and include different types of lava (acid vs basic), dome volcanoes, ash/cinder cones, composite/shield volcanoes, calderas, and basalt plateaus. The document provides details on the formation and characteristics of these various volcanic landforms.
what are Volcanism and volcano,
Distribution of Volcanoes
Kinds of Volcanoes
Types of Volcanic Hazards
Preparing for Volcanic Emergencies
A volcano is generally a conical shaped hill or mountain built by accumulations of lava flows, tephra, and volcanic ash. About 95% of active volcanoes occur at the plate subduction zones and at the mid-oceanic ridges. The other 5% occur in areas associated with lithospheric hot spots. These hot spots have no direct relationships with areas of crustal creation or subduction zones. It is believed that hot spots are caused by plumes of rising magma that have their origin within the asthenosphere.
Over the last 2 million years, volcanoes have been depositing lava, tephra, and ash in particular areas of the globe. These areas occur at hot spots, rift zones, and along plate boundaries where tectonic subduction is taking place within the asthenosphere.
The most prevalent kinds of volcanoes on the Earth's surface are the kind which form the "Pacific Rim of Fire". Those are volcanoes which form as a result of subduction of the nearby lithosphere.
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
The document discusses volcanism and volcanoes. It describes volcanic products like gases, lava, and pyroclastics. It outlines different types of volcanoes including cinder cones, shield volcanoes, composite cones, lava domes, and fissure eruptions. It also discusses volcano distribution patterns and hazards posed by volcanic eruptions like explosions, toxic gases, mudflows, and property damage.
This presentation provides an overview of volcanoes, including their formation from plate tectonics or hotspots, the different types of volcanic features and erupted materials, classifications of volcanic activity, and notable examples. Volcanic activity can have effects on global climate through emissions into the stratosphere and impacts soil through added nutrients.
Volcanism describes the constructive geological process where molten rock erupts from within the earth's crust. There are currently around 550 volcanoes that are considered active. Different types of volcanoes include shield volcanoes like Mauna Loa which erupt fluid basalt lava, cinder cones which form small bowls from ash eruptions, and composite or stratovolcanoes like Mount Rainier that have steep slopes and erupt andesite lava. Monitoring of volcanoes uses techniques like measuring volcanic gas emissions, ground deformation, and remote sensing to detect changes that may forecast eruptions.
Volcanoes form at plate boundaries where tectonic plates are diverging or converging. There are three main types of volcanoes based on location: shield volcanoes at divergent boundaries, stratovolcanoes at subduction zones, and hotspots formed by mantle plumes. Volcanoes pose hazards from lava flows, explosions, and ashfall. Classification systems describe volcanoes based on activity levels from dormant to active. Monitoring systems use alert levels and colors to communicate volcanic unrest and eruptions.
The document summarizes volcanic activity and igneous rock formation. It describes three main types of volcanoes - shield volcanoes which form from fluid basalt and build broad domes, cinder cones which are steep-sided and form from gas-rich eruptions, and composite cones which produce thick layers of lava and ash deposits and can have explosive eruptions. Factors like magma composition, temperature, and dissolved gases determine eruption styles. Intrusive igneous features like batholiths, dikes and sills form as magma cools underground.
This document discusses different types of volcanoes. It provides descriptions of cinder cones, shield volcanoes, composite volcanoes, and lava domes. Cinder cones are symmetrical cones up to 1,200 feet tall formed from a single vent. Shield volcanoes are very broad with shallow slopes and can be over 30,000 feet tall. Composite volcanoes are also known as stratovolcanoes, ranging from 1-10 km wide and up to 10,000 feet tall with steep slopes. They have explosive, dangerous eruptions. Lava domes are much smaller formations that occur when lava is too viscous to flow, piling up in a dome shape around 100 feet tall. Examples of each type
what are Volcanism and volcano,
Distribution of Volcanoes
Kinds of Volcanoes
Types of Volcanic Hazards
Preparing for Volcanic Emergencies
A volcano is generally a conical shaped hill or mountain built by accumulations of lava flows, tephra, and volcanic ash. About 95% of active volcanoes occur at the plate subduction zones and at the mid-oceanic ridges. The other 5% occur in areas associated with lithospheric hot spots. These hot spots have no direct relationships with areas of crustal creation or subduction zones. It is believed that hot spots are caused by plumes of rising magma that have their origin within the asthenosphere.
Over the last 2 million years, volcanoes have been depositing lava, tephra, and ash in particular areas of the globe. These areas occur at hot spots, rift zones, and along plate boundaries where tectonic subduction is taking place within the asthenosphere.
The most prevalent kinds of volcanoes on the Earth's surface are the kind which form the "Pacific Rim of Fire". Those are volcanoes which form as a result of subduction of the nearby lithosphere.
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
The document discusses volcanism and volcanoes. It describes volcanic products like gases, lava, and pyroclastics. It outlines different types of volcanoes including cinder cones, shield volcanoes, composite cones, lava domes, and fissure eruptions. It also discusses volcano distribution patterns and hazards posed by volcanic eruptions like explosions, toxic gases, mudflows, and property damage.
This presentation provides an overview of volcanoes, including their formation from plate tectonics or hotspots, the different types of volcanic features and erupted materials, classifications of volcanic activity, and notable examples. Volcanic activity can have effects on global climate through emissions into the stratosphere and impacts soil through added nutrients.
Volcanism describes the constructive geological process where molten rock erupts from within the earth's crust. There are currently around 550 volcanoes that are considered active. Different types of volcanoes include shield volcanoes like Mauna Loa which erupt fluid basalt lava, cinder cones which form small bowls from ash eruptions, and composite or stratovolcanoes like Mount Rainier that have steep slopes and erupt andesite lava. Monitoring of volcanoes uses techniques like measuring volcanic gas emissions, ground deformation, and remote sensing to detect changes that may forecast eruptions.
Volcanoes form at plate boundaries where tectonic plates are diverging or converging. There are three main types of volcanoes based on location: shield volcanoes at divergent boundaries, stratovolcanoes at subduction zones, and hotspots formed by mantle plumes. Volcanoes pose hazards from lava flows, explosions, and ashfall. Classification systems describe volcanoes based on activity levels from dormant to active. Monitoring systems use alert levels and colors to communicate volcanic unrest and eruptions.
The document summarizes volcanic activity and igneous rock formation. It describes three main types of volcanoes - shield volcanoes which form from fluid basalt and build broad domes, cinder cones which are steep-sided and form from gas-rich eruptions, and composite cones which produce thick layers of lava and ash deposits and can have explosive eruptions. Factors like magma composition, temperature, and dissolved gases determine eruption styles. Intrusive igneous features like batholiths, dikes and sills form as magma cools underground.
This document discusses different types of volcanoes. It provides descriptions of cinder cones, shield volcanoes, composite volcanoes, and lava domes. Cinder cones are symmetrical cones up to 1,200 feet tall formed from a single vent. Shield volcanoes are very broad with shallow slopes and can be over 30,000 feet tall. Composite volcanoes are also known as stratovolcanoes, ranging from 1-10 km wide and up to 10,000 feet tall with steep slopes. They have explosive, dangerous eruptions. Lava domes are much smaller formations that occur when lava is too viscous to flow, piling up in a dome shape around 100 feet tall. Examples of each type
Volcanism is the eruption of molten rock from the earth's surface. Magma rises from the mantle or lower crust through the crust. The viscosity of the magma determines the type of eruption - viscous magma produces explosive eruptions while less viscous magma flows as lava. Volcanoes form at boundaries where tectonic plates meet, such as subduction zones or mid-ocean ridges, and at hot spots that remain stationary under moving plates. The type of volcano depends on the location and consistency of the magma, with examples being shield, composite, and cinder cone volcanoes.
(Yes, a parody of dumb ways to die). Key geography notes I made for a homework task - covering key volcanic hazards as part of tectonics, including examples and case studies.
This document provides an introduction to volcanology. It defines a volcano as an opening in the Earth's surface through which lava, gases, and rock fragments erupt. It describes how magma rises from deep underground to form a magma chamber near the surface, which then erupts through a vent to form a volcano. Key parts of a volcano include the vent, crater, lava flows, and sometimes parasitic cones. Volcanoes are often located along tectonic plate boundaries like the Ring of Fire around the Pacific. Earthquakes can provide information about volcanic structures and pathways. Volcanology studies volcanoes and related phenomena, while volcanism describes the geological process of material emerging from the Earth's interior.
Volcanoes,Fault Zone And Earthquakes,,Seismograph,Body Waves,Features Of Volc...Dhrupal Patel
briefly introduction about Volcanoes,Fault Zone And Earthquakes,,Seismograph,Body Waves,Features Of Volcanism,Volcanic EruptionsVolcanic Products,Locating Earthquakes,Measuring The “Size” Of Earthquakes,World Earthquake Distribution,Effects Of Earthquakes
Volcanic Activity
- Volcanoes form when magma reaches the Earth's surface, causing eruptions of lava and ash. They occur at destructive and constructive plate boundaries.
- The Mid Atlantic Ridge under the Atlantic Ocean was formed when plates separated and lava came to the surface, cooled and hardened.
- Most earthquakes and volcanoes occur along the Pacific Ring of Fire.
Grade 8 Integrated Science Chapter 15 Lesson 2 on volcanoes. This lesson goes into detail about volcanoes, plate boundaries, lava chemistry, eruption types, and volcano types. The purpose of this lesson is for students to understand where and why volcanoes form and what factors cause differing volcanic features.
Volcanism refers to the ejection of molten materials from a volcano. A volcano is a vent in the earth's crust through which gases and hot materials are expelled. These ejected materials accumulate around the vent to form a volcanic cone. The top of the volcano is called the crater. There are 32 volcanoes in the Philippines, with Mount Mayon being the most famous due to its perfect cone shape, which volcanologists fear has been changed by recent eruptions.
Volcanoes form when hot molten rock (magma) rises from below the Earth's surface and erupts. They consist of a vent, conduit and surrounding cone built from erupted material. Most volcanoes occur at plate boundaries or hot spots. Magma rises due to lower density and pressure changes, erupting either explosively with gas-rich magma or effusively with low-viscosity magma. Eruptions produce hazards like lava flows, pyroclastic flows and falls. Notable examples include Vesuvius destroying Pompeii and Krakatoa's powerful 1883 eruption. Supervolcanoes are capable of much larger eruptions than normal volcanoes.
This document discusses different types of volcanoes and their characteristics. It describes three main types: composite volcanoes, cinder cones, and shield volcanoes. Composite volcanoes are large, steep mountains formed from layers of lava and pyroclastic material. They often have small craters and include volcanoes like Krakatoa. Cinder cones are small, steep mountains composed of hardened volcanic cinders and ash. Shield volcanoes are enormous mountains thousands of kilometers high, like Mauna Loa, formed from numerous mild lava flows. The document provides details on the components and eruptive behaviors of each type.
The document discusses different types of volcanoes including active, dormant, and extinct volcanoes. It provides definitions and examples for each type. An active volcano is considered one that is currently erupting or showing signs of unrest. A dormant volcano has not erupted in historical times but could become active again if conditions changed. An extinct volcano is one that scientists consider unlikely to erupt again due to lack of magma supply. The effects of volcanic eruptions and features like lahars (volcanic mudflows) are also summarized.
This document discusses volcanoes and volcanic hazards. It begins by defining a volcano as a vent connecting molten rock below the Earth's surface to the surface. Volcanoes erupt when magma rises due to being less dense than surrounding rock. The type of eruption depends on gas and viscosity levels, with more gas and viscosity causing explosive eruptions. Volcanic hazards include pyroclastic flows, lava flows, ash falls, and lahars. Monitoring of seismic activity, deformation, and gas output can help predict eruptions and minimize risks from active volcanoes.
1. The document describes different types of volcanoes and volcanic eruptions including Hawaiian, Strombolian, Vulcanian, and Plinian eruptions.
2. It also discusses volcanic materials like andesite, basalt, dacite, obsidian, peridotite, rhyolite, tuff, and volcanic gases.
3. Volcanic processes refer to eruptive and non-eruptive activities like decompression of rising magma and vapor pressure increases during magma crystallization.
Volcanology is the study of volcanoes, lava, magma, and related geological phenomena. A volcano forms when magma rises from deep in the Earth's mantle and erupts on the surface. As more magma rises, it forms a magma chamber and conduit leading to a vent. Eruptions through the vent build the volcano over time. There are four main types of volcanism related to mid-ocean ridges, subduction zones, hotspots, and flood volcanism. Heat sources for volcanism include radioactive decay, accretion during planetary formation, tidal effects, and core formation deep within the Earth.
Volcanoes form at constructive and destructive plate boundaries. At constructive boundaries, volcanoes form as magma rises through gaps created as plates move apart. These volcanoes are usually shield volcanoes. At destructive boundaries, one plate is subducted and melts, creating excess magma that erupts violently as composite volcanoes. Volcanoes can be active and currently erupting, dormant but capable of future eruptions, or extinct and not likely to erupt again. Hot spot volcanoes form from stationary plumes of magma rising through weak crust, creating island chains as plates move over hot spots.
This document provides information about a station-based volcano education program. The stations cover topics like classifying volcanoes, eruption types, magma composition, and volcanic hazards and benefits. At each station, students fill out worksheets or do activities to learn about parts of volcanoes, what causes eruptions, how silica and water content determine explosivity, different lava and pyroclastic material types, and examples of shield, cinder cone, and composite volcanoes. Math problems calculate totals, differences, distances, times, costs, and rates related to volcanic eruptions, ash and lava flows, and operating robots. The goal is to help students understand volcanoes through hands-on activities at multiple informative stations.
Volcanoes form as a result of the Earth releasing its internal heat through the crust. Molten rock from the mantle melts and rises to the surface through the crust, erupting and releasing gases. There are three main types of volcanoes defined by their location - at divergent plate boundaries where plates pull apart, at convergent boundaries where plates collide, and at hot spots in the middle of plates. Volcanoes can erupt explosively or quietly and pose volcanic hazards like pyroclastic flows, gases, and lava.
Volcanoes: Its characteristics and products.Mrityunjay Jha
This document provides an overview of volcanoes and volcanic activity. It defines key volcanic features and terms like magma, vent, lava, and ash. It describes the three main types of volcanoes based on activity level - active, dormant, and extinct. Different types of volcanic eruptions and the factors that influence eruption type are outlined. Common volcanic landforms like lava flows with different surface textures, hot springs, fumaroles, and mud volcanoes are also summarized. The document concludes by reviewing the main areas of volcanic activity around the world.
This document provides an overview of volcanoes. It begins by defining a volcano as a vent in the Earth's surface through which molten rock and gases erupt. It then discusses the internal structure of volcanoes including magma, which is molten rock below the surface. The causes of volcanism are explained in relation to plate tectonics. Different types of volcanoes are classified based on factors like eruption intensity, magma composition, and shape. Volcanic landforms that form from intrusive and extrusive volcanic activity are also outlined. In summary, the document covers the key components and processes involved in volcanism.
Volcanoes form as magma rises up from below the Earth's crust and erupts onto the surface. The type and violence of volcanic eruptions depends on factors like the amount of gas in the magma and how easily it can escape. The most common types of volcanoes are composite volcanoes, cinder cone volcanoes, and shield volcanoes, which erupt in different ways and produce different landforms. Most volcanoes occur along plate boundaries in the Pacific Ring of Fire and other convergence zones.
This document provides information about volcanoes, including definitions, types, and eruption processes. It begins by defining a volcano and its key components. It then describes the three most common types of volcanoes - stratovolcanoes, shield volcanoes, and caldera volcanoes - and provides examples of each. It distinguishes between active, inactive, and potentially active volcanoes, and lists some of the most notable examples in the Philippines. Finally, it outlines different types of volcanic eruptions and describes the hazards they can produce, such as pyroclastic flows, volcanic bombs, and lahars.
Volcanoes are openings in the Earth's crust through which magma and gases erupt. There are several types of volcanoes defined by their shape and eruptive activity. Shield volcanoes have gentle slopes and erupt non-violently, building up slowly over time. Composite volcanoes have steep slopes and erupt violently, destroying the existing cone. Caldera volcanoes form large depressions when the magma chamber collapses inward after a very large eruption. Volcanic eruptions occur when pressure from gases and magma is released, sometimes due to earthquakes shifting tectonic plates. Eruptions can have devastating impacts through lava flows, ash falls, pyroclastic flows, and lah
Volcanoes form when tectonic plates collide and one plate slides under another in the process of subduction. Most volcanoes occur near plate boundaries, especially around the Pacific Ocean basin known as the Ring of Fire. The Ring of Fire contains over 75% of the world's active volcanoes, including 452 volcanoes dotted around the boundary. Volcanic hotspots also cause volcanism, where thermal plumes rise from the Earth's mantle and melt the overlying rock. Different types of volcanic eruptions occur depending on the viscosity of the magma and amount of dissolved gases. Explosive eruptions are violent while effusive eruptions steadily flow lava. Scientists monitor ground deformation, gas emissions, and
Volcanism is the eruption of molten rock from the earth's surface. Magma rises from the mantle or lower crust through the crust. The viscosity of the magma determines the type of eruption - viscous magma produces explosive eruptions while less viscous magma flows as lava. Volcanoes form at boundaries where tectonic plates meet, such as subduction zones or mid-ocean ridges, and at hot spots that remain stationary under moving plates. The type of volcano depends on the location and consistency of the magma, with examples being shield, composite, and cinder cone volcanoes.
(Yes, a parody of dumb ways to die). Key geography notes I made for a homework task - covering key volcanic hazards as part of tectonics, including examples and case studies.
This document provides an introduction to volcanology. It defines a volcano as an opening in the Earth's surface through which lava, gases, and rock fragments erupt. It describes how magma rises from deep underground to form a magma chamber near the surface, which then erupts through a vent to form a volcano. Key parts of a volcano include the vent, crater, lava flows, and sometimes parasitic cones. Volcanoes are often located along tectonic plate boundaries like the Ring of Fire around the Pacific. Earthquakes can provide information about volcanic structures and pathways. Volcanology studies volcanoes and related phenomena, while volcanism describes the geological process of material emerging from the Earth's interior.
Volcanoes,Fault Zone And Earthquakes,,Seismograph,Body Waves,Features Of Volc...Dhrupal Patel
briefly introduction about Volcanoes,Fault Zone And Earthquakes,,Seismograph,Body Waves,Features Of Volcanism,Volcanic EruptionsVolcanic Products,Locating Earthquakes,Measuring The “Size” Of Earthquakes,World Earthquake Distribution,Effects Of Earthquakes
Volcanic Activity
- Volcanoes form when magma reaches the Earth's surface, causing eruptions of lava and ash. They occur at destructive and constructive plate boundaries.
- The Mid Atlantic Ridge under the Atlantic Ocean was formed when plates separated and lava came to the surface, cooled and hardened.
- Most earthquakes and volcanoes occur along the Pacific Ring of Fire.
Grade 8 Integrated Science Chapter 15 Lesson 2 on volcanoes. This lesson goes into detail about volcanoes, plate boundaries, lava chemistry, eruption types, and volcano types. The purpose of this lesson is for students to understand where and why volcanoes form and what factors cause differing volcanic features.
Volcanism refers to the ejection of molten materials from a volcano. A volcano is a vent in the earth's crust through which gases and hot materials are expelled. These ejected materials accumulate around the vent to form a volcanic cone. The top of the volcano is called the crater. There are 32 volcanoes in the Philippines, with Mount Mayon being the most famous due to its perfect cone shape, which volcanologists fear has been changed by recent eruptions.
Volcanoes form when hot molten rock (magma) rises from below the Earth's surface and erupts. They consist of a vent, conduit and surrounding cone built from erupted material. Most volcanoes occur at plate boundaries or hot spots. Magma rises due to lower density and pressure changes, erupting either explosively with gas-rich magma or effusively with low-viscosity magma. Eruptions produce hazards like lava flows, pyroclastic flows and falls. Notable examples include Vesuvius destroying Pompeii and Krakatoa's powerful 1883 eruption. Supervolcanoes are capable of much larger eruptions than normal volcanoes.
This document discusses different types of volcanoes and their characteristics. It describes three main types: composite volcanoes, cinder cones, and shield volcanoes. Composite volcanoes are large, steep mountains formed from layers of lava and pyroclastic material. They often have small craters and include volcanoes like Krakatoa. Cinder cones are small, steep mountains composed of hardened volcanic cinders and ash. Shield volcanoes are enormous mountains thousands of kilometers high, like Mauna Loa, formed from numerous mild lava flows. The document provides details on the components and eruptive behaviors of each type.
The document discusses different types of volcanoes including active, dormant, and extinct volcanoes. It provides definitions and examples for each type. An active volcano is considered one that is currently erupting or showing signs of unrest. A dormant volcano has not erupted in historical times but could become active again if conditions changed. An extinct volcano is one that scientists consider unlikely to erupt again due to lack of magma supply. The effects of volcanic eruptions and features like lahars (volcanic mudflows) are also summarized.
This document discusses volcanoes and volcanic hazards. It begins by defining a volcano as a vent connecting molten rock below the Earth's surface to the surface. Volcanoes erupt when magma rises due to being less dense than surrounding rock. The type of eruption depends on gas and viscosity levels, with more gas and viscosity causing explosive eruptions. Volcanic hazards include pyroclastic flows, lava flows, ash falls, and lahars. Monitoring of seismic activity, deformation, and gas output can help predict eruptions and minimize risks from active volcanoes.
1. The document describes different types of volcanoes and volcanic eruptions including Hawaiian, Strombolian, Vulcanian, and Plinian eruptions.
2. It also discusses volcanic materials like andesite, basalt, dacite, obsidian, peridotite, rhyolite, tuff, and volcanic gases.
3. Volcanic processes refer to eruptive and non-eruptive activities like decompression of rising magma and vapor pressure increases during magma crystallization.
Volcanology is the study of volcanoes, lava, magma, and related geological phenomena. A volcano forms when magma rises from deep in the Earth's mantle and erupts on the surface. As more magma rises, it forms a magma chamber and conduit leading to a vent. Eruptions through the vent build the volcano over time. There are four main types of volcanism related to mid-ocean ridges, subduction zones, hotspots, and flood volcanism. Heat sources for volcanism include radioactive decay, accretion during planetary formation, tidal effects, and core formation deep within the Earth.
Volcanoes form at constructive and destructive plate boundaries. At constructive boundaries, volcanoes form as magma rises through gaps created as plates move apart. These volcanoes are usually shield volcanoes. At destructive boundaries, one plate is subducted and melts, creating excess magma that erupts violently as composite volcanoes. Volcanoes can be active and currently erupting, dormant but capable of future eruptions, or extinct and not likely to erupt again. Hot spot volcanoes form from stationary plumes of magma rising through weak crust, creating island chains as plates move over hot spots.
This document provides information about a station-based volcano education program. The stations cover topics like classifying volcanoes, eruption types, magma composition, and volcanic hazards and benefits. At each station, students fill out worksheets or do activities to learn about parts of volcanoes, what causes eruptions, how silica and water content determine explosivity, different lava and pyroclastic material types, and examples of shield, cinder cone, and composite volcanoes. Math problems calculate totals, differences, distances, times, costs, and rates related to volcanic eruptions, ash and lava flows, and operating robots. The goal is to help students understand volcanoes through hands-on activities at multiple informative stations.
Volcanoes form as a result of the Earth releasing its internal heat through the crust. Molten rock from the mantle melts and rises to the surface through the crust, erupting and releasing gases. There are three main types of volcanoes defined by their location - at divergent plate boundaries where plates pull apart, at convergent boundaries where plates collide, and at hot spots in the middle of plates. Volcanoes can erupt explosively or quietly and pose volcanic hazards like pyroclastic flows, gases, and lava.
Volcanoes: Its characteristics and products.Mrityunjay Jha
This document provides an overview of volcanoes and volcanic activity. It defines key volcanic features and terms like magma, vent, lava, and ash. It describes the three main types of volcanoes based on activity level - active, dormant, and extinct. Different types of volcanic eruptions and the factors that influence eruption type are outlined. Common volcanic landforms like lava flows with different surface textures, hot springs, fumaroles, and mud volcanoes are also summarized. The document concludes by reviewing the main areas of volcanic activity around the world.
This document provides an overview of volcanoes. It begins by defining a volcano as a vent in the Earth's surface through which molten rock and gases erupt. It then discusses the internal structure of volcanoes including magma, which is molten rock below the surface. The causes of volcanism are explained in relation to plate tectonics. Different types of volcanoes are classified based on factors like eruption intensity, magma composition, and shape. Volcanic landforms that form from intrusive and extrusive volcanic activity are also outlined. In summary, the document covers the key components and processes involved in volcanism.
Volcanoes form as magma rises up from below the Earth's crust and erupts onto the surface. The type and violence of volcanic eruptions depends on factors like the amount of gas in the magma and how easily it can escape. The most common types of volcanoes are composite volcanoes, cinder cone volcanoes, and shield volcanoes, which erupt in different ways and produce different landforms. Most volcanoes occur along plate boundaries in the Pacific Ring of Fire and other convergence zones.
This document provides information about volcanoes, including definitions, types, and eruption processes. It begins by defining a volcano and its key components. It then describes the three most common types of volcanoes - stratovolcanoes, shield volcanoes, and caldera volcanoes - and provides examples of each. It distinguishes between active, inactive, and potentially active volcanoes, and lists some of the most notable examples in the Philippines. Finally, it outlines different types of volcanic eruptions and describes the hazards they can produce, such as pyroclastic flows, volcanic bombs, and lahars.
Volcanoes are openings in the Earth's crust through which magma and gases erupt. There are several types of volcanoes defined by their shape and eruptive activity. Shield volcanoes have gentle slopes and erupt non-violently, building up slowly over time. Composite volcanoes have steep slopes and erupt violently, destroying the existing cone. Caldera volcanoes form large depressions when the magma chamber collapses inward after a very large eruption. Volcanic eruptions occur when pressure from gases and magma is released, sometimes due to earthquakes shifting tectonic plates. Eruptions can have devastating impacts through lava flows, ash falls, pyroclastic flows, and lah
Volcanoes form when tectonic plates collide and one plate slides under another in the process of subduction. Most volcanoes occur near plate boundaries, especially around the Pacific Ocean basin known as the Ring of Fire. The Ring of Fire contains over 75% of the world's active volcanoes, including 452 volcanoes dotted around the boundary. Volcanic hotspots also cause volcanism, where thermal plumes rise from the Earth's mantle and melt the overlying rock. Different types of volcanic eruptions occur depending on the viscosity of the magma and amount of dissolved gases. Explosive eruptions are violent while effusive eruptions steadily flow lava. Scientists monitor ground deformation, gas emissions, and
This document discusses volcanoes and earthquakes. It begins by explaining that tectonic movements like earthquakes and volcanoes can abruptly change the Earth's surface features. It then defines earthquakes as vibrations produced in rocks, and describes the different types of earthquake waves. Causes of earthquakes include movement along faults in the Earth's crust. Volcanoes originate from magma pockets that form below the Earth's surface due to decreased pressure. The document outlines different types of volcanoes based on eruption style and activity level. It also describes the products of volcanic eruptions, including solid, liquid, and gaseous materials. Various landforms associated with volcanoes are also explained, such as volcanic cones, ash
Volcanoes are openings in the Earth's crust through which magma and gases erupt. There are several types of volcanoes defined by their structure and eruptive activity. Shield volcanoes have gentle slopes and erupt non-violently, building up over time. Composite and cinder cone volcanoes have steeper slopes and more explosive eruptions. Caldera volcanoes form large depressions when the magma chamber collapses. Volcanic activity occurs at plate boundaries and hot spots due to pressure buildup underground.
Volcanoes are openings in the Earth's crust through which magma and gases erupt. There are several types of volcanoes defined by their structure and eruptive activity. Shield volcanoes have gentle slopes and erupt non-violently, building up over time. Composite and cinder cone volcanoes have steeper slopes and more explosive eruptions. Caldera volcanoes form large depressions when the magma chamber collapses. Volcanic activity occurs at plate boundaries and hot spots due to pressure from shifting crust and rising magma. Eruptions damage property and endanger life through lava, ash, pyroclastic flows, and toxic gases.
Geohazards are natural hazards caused by geological processes within the Earth, such as volcanoes, earthquakes, floods, tsunamis, and cyclones, which can cause damage and loss of life. Earthquakes occur along faults in the Earth's crust due to the sudden release of accumulated strain, generating seismic waves that can damage infrastructure and trigger other hazards like tsunamis and landslides. Volcanic eruptions result from the buildup of pressure from magma and gases below the Earth's surface, which are released through explosions or lava flows that can endanger nearby populations and environments.
A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth. When pressure builds up, eruptions occur. Gases and rock shoot up through the opening and spill over or fill the air with lava fragments. Eruptions can cause lateral blasts, lava flows, hot ash flows, mudslides, avalanches, falling ash and floods. Volcano eruptions have been known to knock down entire forests. An erupting volcano can trigger tsunamis, flash floods, earthquakes, mudflows and rockfalls.
This document describes various geologic hazards such as earthquakes, volcanic eruptions, and landslides. It defines key terms and processes associated with these hazards, such as tephra, pyroclastic flows, lahars, liquefaction, and ground shaking. It also notes that the Philippines is highly susceptible to natural disasters due to its location along the Ring of Fire, and experiences many deadly typhoons, earthquakes, and volcanic eruptions that negatively impact people and the environment.
This document describes various geologic hazards such as earthquakes, volcanic eruptions, and landslides. It defines key terms and processes associated with these hazards, such as tephra, pyroclastic flows, lahars, liquefaction, and ground shaking. It also notes that the Philippines is highly susceptible to natural disasters due to its location along the Ring of Fire, and experiences many deadly typhoons, earthquakes, and volcanic eruptions that negatively impact people and the environment.
Volcanoes form when molten rock erupts from the earth's crust. There are several types of volcanoes including shield volcanoes, cinder cone volcanoes, composite volcanoes, caldera volcanoes, and fissure volcanoes. Volcanoes are most common along tectonic plate boundaries in the Pacific Ring of Fire and where convection currents in the mantle upwell. Eruptions occur via explosions that release underground gases and magma due to a decrease in pressure from earthquakes or other crustal shifts. Major eruptions can cause widespread destruction through lava flows, poisonous gases, ash falls, and landslides.
This document provides an overview of magma, volcanoes, and volcanic eruptions. It discusses the following key points in 3 sentences:
Magma is molten rock beneath the Earth's surface that rises towards the surface through vents called volcanoes. There are different types of volcanoes that produce eruptions ranging from gentle flows to catastrophic explosions, depending on the viscosity and gas content of the magma. The composition and viscosity of magmas influence the type of eruption, whether nonexplosive eruptions producing lava flows or explosive eruptions ejecting tephra and forming eruption columns and pyroclastic flows.
This document provides an overview of magma, volcanoes, and volcanic eruptions. It discusses how magma forms below Earth's surface and rises toward the surface through volcanoes. There are different types of volcanoes that produce nonexplosive or explosive eruptions depending on factors like magma viscosity and gas content. Eruptions can produce hazards like pyroclastic flows, tephra falls, lahars, and poisonous gases. The majority of volcanic activity occurs under the oceans and goes unobserved.
Magma and Volcanoes
The document discusses magma, volcanoes, and volcanic eruptions. It defines magma as molten rock beneath Earth's surface that rises toward the surface through vents called volcanoes. There are different types of volcanoes that produce different styles of eruptions from gentle to explosive, depending on factors like magma composition and viscosity. The three main types of magma are basaltic, andesitic, and rhyolitic. Explosive eruptions can produce devastating pyroclastic flows and tephra falls while nonexplosive eruptions form lava flows.
This document describes different types of volcanoes including composite volcanoes, shield volcanoes, cinder cones, and spatter cones. Composite volcanoes are tall and conical, built up from layers of lava and rock fragments. Shield volcanoes are wide and gently sloping due to fluid basaltic lava. Cinder cones form steep hills above vents and are built from ejected lava fragments. Spatter cones consist of welded lava clots that form around vents. Volcanic eruptions depend on factors like silica and water content, which influence lava viscosity and explosivity. Eruptions can range from gentle lava flows to violent ejections of pyroclastic material.
This document describes different types of volcanoes including composite volcanoes, shield volcanoes, cinder cones, and spatter cones. Composite volcanoes are tall and conical, built up from layers of lava and rock. Shield volcanoes are wide and gently sloping due to fluid basalt lava. Cinder cones form steep hills above vents and are built from ejected lava fragments. Spatter cones consist of welded lava clots ejected from vents. The document also discusses volcanic eruptions and their impacts.
Types of Volcanoes presentatiom slides for grade 9rolanaribato30
This document discusses different types of volcanoes including composite volcanoes, shield volcanoes, cinder cones, and spatter cones. Composite volcanoes are formed from layers of lava and rock fragments, while shield volcanoes are formed from fluid basaltic lava flows. Cinder cones are steep, conical hills formed from ejected lava fragments, and spatter cones are accumulations of spatter clots that form around individual vents. The document also covers volcanic eruptions, impacts, and how volcanoes erupt by forcing magma through conduits and vents in various eruption styles.
This document describes different types of volcanoes including composite volcanoes, shield volcanoes, cinder cones, and spatter cones. Composite volcanoes are tall and conical, built up from layers of lava and rock fragments. Shield volcanoes are wide and gently sloping due to fluid basaltic lava flows. Cinder cones form steep hills above vents and are built from ejected volcanic fragments. Spatter cones consist of welded together lava clots ejected from vents. The document also discusses volcanic eruptions and their varying impacts.
This document discusses volcanoes and volcanic eruptions. It begins by defining vulcanism as the eruption of magma onto the earth's surface through a vent. It then describes the anatomy of volcanoes and how they are formed from magma rising from the earth's mantle. The document outlines different tectonic settings for volcanoes and the typical magma and eruption types associated with each setting. It discusses the mechanics and styles of volcanic eruptions including phreatic, phreatomagmatic, Strombolian, Vulcanian and Plinian eruptions. Finally, it notes some constructive aspects of volcanism such as providing nutrients to soil and potential for geothermal energy.
Volcanoes form at boundaries where tectonic plates meet, such as at divergent boundaries like the Mid-Atlantic Ridge or at convergent boundaries. The type of eruption depends on the composition of the magma and amount of gases; basaltic magma produces quiet eruptions while magma rich in silica or water causes explosive eruptions. The resulting volcano shape is also influenced by the eruption - shield volcanoes form from fluid basalt lava, cinder cones from tephra ejected in explosions, and composite volcanoes feature layers from both eruption types.
2. What is a Volcano?
A volcano is a vent, or opening in the crust from
which pour molten rock, rock debris, gases and steam
The name comes from the Roman god of fire Vulcan.
When magma penetrates the surface it is known as
lava.
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6. Global distribution of volcanoes
Most volcanoes are found along convergent and
divergent plate boundaries.
At these points there are molten rocks and magma to
supply the volcanoes.
There are about 1300 potentially active volcanoes in
the world.
A small number of volcanoes are along way from
plate boundaries known as hot spots.
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7. Global distribution of volcanoes
At these points the temperature at the boundary of
the mantle ad crust is unusually high and there are
lines of weakness in the crust which magma can
follow to reach the surface.
An example of an hot spot is the Hawaiian Islands
Some hot spots can also be found beneath continents
such as Yellowstone Basin in the USA
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9. Volcanic Eruption?
The sudden occurrence of a violent discharge of
steam and volcanic material.
An eruption begins when pressure on a magma
chamber forces magma up through the conduit and
out the volcano's vents.
When the magma chamber has been completely
filled, the type of eruption partly depends on the
amount of gases and silica in the magma.
The amount of silica determines how sticky (level of
viscosity) the magma is and water provides the
explosive potential of steam.
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10. Stages of a volcano
Active- when eruptions occur at frequent intervals
Dormant-when eruptions are infrequent and one has
not occurred for some time
Extinct- when it is thought a volcano will never erupt
again.
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11. Ways volcano affect humans
Lava flows
Tephra
Pyroclastic flows
Volcanic gases
Lahars
Tsunamis
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12. Lava flows
Lava flows are streams of molten rock that pour or
ooze from an erupting vent.
Lava is erupted during either nonexplosive activity or
explosive lava fountains.
Lava flows destroy everything in their path, but most
move slowly enough that people can move out of the
way.
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13. Lava flows
The speed at which lava moves across the ground
depends on several factors, including :
(1) type of lava erupted and its viscosity;
(2) steepness of the ground over which it travels;
(3) whether the lava flows as a broad sheet, through a
confined channel, or down a lava tube;
(4) rate of lava production at the vent.
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15. Tephra
When a volcano erupts it will sometimes eject material
such as rock fragments into the atmosphere. This
material is known as tephra.
The largest pieces of tephra (greater than 64 mm) are
called blocks and bombs. Blocks and bombs are normally
shot ballistically from the volcano (refer to the gas thrust
zone described in the direct blast section).
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16. Tephra
Because these fragments are so large they fall out near
their source. Blocks and bombs as large as 8-30 tons have
fallen as far away as 1 km from their source (Bryant,
1991).
Small blocks and bombs have been known to travel as far
away as 20-80 km !
Some of these blocks and bombs can have velocities of
75-200 m/s
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18. Pyroclastic flows
Pyroclastic flows are fluidized masses of rock fragments
and gases that move rapidly in response to gravity.
Pyroclastic flows can form in several different ways.
They can form when an eruption column collapses, or as
the result of gravitational collapse or explosion on a lava
dome or lava flow.
These flows are more dense than pyroclastic surges and
can contain as much as 80 % unconsolidated material.
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19. Pyroclastic flows
The flow is fluidized because it contains water and gas
from the eruption, water vapor from melted snow and
ice, and air from the flow overriding air as it moves
downslope.
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21. Volcanic gases
Magma contains dissolved gases that are released into
the atmosphere during eruptions.
Gases are also released from magma that either
remains below ground (for example, as an intrusion)
or is rising toward the surface.
In such cases, gases may escape continuously into the
atmosphere from the soil, volcanic vents, fumaroles,
and hydrothermal systems.
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22. Volcanic gases
At high pressures deep beneath the earth's surface,
volcanic gases are dissolved in molten rock.
But as magma rises toward the surface where the
pressure is lower, gases held in the melt begin to form
tiny bubbles.
The increasing volume taken up by gas bubbles makes
the magma less dense than the surrounding rock, which
may allow the magma to continue its upward journey.
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24. Lahars
Lahar is an Indonesian term that describes a hot or
cold mixture of water and rock fragments flowing
down the slopes of a volcano and (or) river valleys.
When moving, a lahar looks like a mass of wet
concrete that carries rock debris ranging in size from
clay to boulders more than 10 m in diameter.
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25. Lahars
Lahars vary in size and speed. Small lahars less than a
few meters wide and several centimeters deep may
flow a few meters per second. Large lahars hundreds
of meters wide and tens of meters deep can flow
several tens of meters per second--much too fast for
people to outrun.
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27. Tsunamis
A series of water waves caused by the displacement of
a large volume of a body of water, typically an ocean
or a large lake.
Earthquakes, volcanic eruptions and other
underwater explosions, landslides, glacier calvings,
meteorite impacts and other disturbances above or
below water all have the potential to generate a
tsunami.
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30. Dyke
When a mass of magma cuts across bedding planes, it
forms a wall-like feature called a dyke.
Sometimes the rocks on either side of a dyke are more
resistant to erosion.
When this happens, the dyke forms a depression. Dykes
sometimes occur in swarms, as in Arran and parts of
western Scotland and northern Ireland.
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32. Sill
When a sheet of magma lies along a bedding plane it
forms a structure called a sill.
Some sills form ridge-like escarpments when exposed
by erosion.
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33. Laccolith
A sheet intrusion that has been injected between two
layers of sedimentary rock. The pressure of the
magma is high enough that the overlying strata are
forced upward, giving the laccolith a dome or
mushroom-like form with a generally planar base.
Laccoliths tend to form at relatively shallow depths
and are typically formed by relatively viscous
magmas, such as those that crystallize to diorite,
granodiorite, and granite.
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35. Batholith
This is a very large mass of magma which
accumulates in the crust. Sometimes it forms the root
or core of a mountain.
Batholiths are made of granite and they form surface
features only after they have been exposed by
denudation.
Batholits are exposed at the suface in south-west
England where they form Dartmoor, Bodmin Moor,
Land's End and the Scilly Isles. These are the cores of
an ancient mountain chain the tops of which have
long since been removed by erosion.
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37. Extrusive volcanic features
Acid lava
Basic lava
Dome volcanoes
Ash and cinder cones
Composite cones
Shield volcanoes
Calderas
Basalt plateaus
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38. Extrusive volcanic features
Magma sometimes reaches the surface through a vent
(hole), or a fissure (crack) in the surface rocks. When
magma emerges at the surface it is called lava.
If lava emerges via a vent, it usually builds up a
volcano, which is a cone-shaped mound.
If it emerges from a fissure, it may build up a lava
plain, or a lava plateau. Volcanic eruptions also take
place on some ocean floors.
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39. Acid lava
Acid lava comes from composite cone volcanoes, is
slow moving and viscous
Acid lava is produced when there is subduction at
destructive plate boundaries.
This lava is silica-rich and has temperatures of about
800°C.
It cools and solidifies quickly and produces steep
sided volcanoes.
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40. Acid lava
As it solidifies quickly, it may solidify in the central
pipe, blocking the passageway and causing a buildup
of pressure, which produces violent eruptions.
The solidified lava forms sheets of rough, jagged
rocks called aá. Flows of boulders and rubble called
block rubble and mounds of lava called domes are
also formed.
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42. Basic lava
Basic lava comes from shield volcanoes, is runny and
flows faster.
Basic lava is produced at constructive plate
boundaries.
This lava is rich in iron and magnesium and is rather
fluid. It has a temperature of about 1200°C.
It flows for a distance before solidifying and forms
gently sloping volcanoes. The lava solidifies into
smooth, folded sheets of rock called pahoehoe.
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44. Dome Volcanoes
A dome volcano is a round shaped mountain made of
viscous lava.
The lava has a high silica content that prevents the
lava from flowing very far from its vent.
Most domes are formed by dacite and rhyolite lavas.
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47. Ash and cinder cones
Lava is blown to great heights when it is violently
ejected, and it breaks into small fragments which fall
back to earth and build up a cone.
Good examples of ash and cinder cones are Volcano
De Fuego (Guatemala) and Paricutin (Mexico).
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48. Composite cones
This type of cone is formed of alternate layers of lava
and ash.
The volcano begins each eruption with great violence
forming a layer of ash.
As the eruption proceeds, the violence ceases and
lava pours out forming a layer on top of the ash. Lava
often escapes from the sides of the cone where it
builds up small conelets
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50. Shield volcanoes
A shield volcano is a type of volcano usually built
almost entirely of fluid lava flows.
They are named for their large size and low profile,
resembling a warrior's shield.
This is caused by the highly fluid lava they erupt,
which travels farther than lava erupted from more
explosive volcanoes.
This results in the steady accumulation of broad
sheets of lava, building up the shield volcano's
distinctive form. Shield volcanoes contain low
viscosity magma making it have flowing mafic lava.
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53. Calderas
These are ones where the diameter of the circular to
oval crater exceeds 1 mile.
These form when so much lava is erupted (blown
out) so rapidly it partially empties the underlying
magma chamber.
When this happens the summit of the volcanic
structure collapses into the emptied magma chamber.
Typically the erupted material occurs as airfall or
pyroclastic flows.
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56. Basalt Plateau
One or a succession of high-temperature basaltic lava
flows from fissure eruptions which accumulate to
form a plateau. Also known as flood basalt.
Example the Indian Deccan
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