Volcanoes PDF

Volcanoes Volcanoes Volcanoes Volcanoes What is a volcano? A vent, hill or mountain from which molten or hot rocks with gaseous material have been ejected *formed by removal of pre-existing material or by accumulation of ejected materials What is a volcano? A vent,...

Volcanoes Volcanoes Volcanoes Volcanoes What is a volcano? A vent, hill or mountain from which molten or hot rocks with gaseous material have been ejected *formed by removal of pre-existing material or by accumulation of ejected materials What is a volcano? A vent, hill or mountain from which molten or hot rocks with gaseous material have been ejected *formed by removal of pre-existing material or by accumulation of ejected materials Volcanoes Volcanoes Volcanoes Volcanoes Magmatic chamber: is a deposit of molten rock or magma that lies beneath the earth’s crust at high pressure Main Vent is the main opening or outlet on the surface of a volcano that emits lava, gases, ash or other volcanic materials. Conduit is an underground central tube-like or pipe-like structure of a volcano that connects the magma chamber to the crater through which the magma travels. Other Geologic features of a volcano: Other Geologic features of a volcano: Side Vent is a smaller outlet through which magma escapes. Other Geologic features of a volcano: Crater is the mouth of the volcano which is a funnel-shaped or bowlshaped hollow at the top of the vent from where magma, ash and gas  Other Geologic Lava is a molten rock which is given off onto the surface of the Earth when features of a volcano: a volcano erupts.  Other Geologic Ash and Gas Cloud is a features of mixtures of rock, minerals, glass particles of a volcano: and gases expelled or pushed out of the volcano during volcanic eruption. Other Geologic features of a volcano: Other Geologic features of a volcano: Classification of Volcanoes: Based on structure There are different types of volcanoes, which depend on the place where they originated, their shape and size, and even the materials they expel.  TYPES OF VOLCANOES: ACCORDING TO THEIR ACTIVITY Active volcanoes are those volcanoes that have had at least one eruption during the past 10,000 years. They are those that erupted recently and still showing regular activity like emission of gases, lava and ash flows. Inactive volcanoes are those that have not erupted for the last 10,000 years and is not expected to erupt again in a comparable time scale of the future. Potentially active volcanoes are those that have no records of volcanic activity but are morphologically young-looking. TYPES OF VOLCANIC ERRUPTION  "Mount Apo: Preparing for the Worst" THE MORE VISCOUS A LIQUID IS, AND THE MORE GAS IT CONTAINS, THE MORE EXPLOSIVE THE ERUPTION WILL BE.  VISCOSITY the magma’s ability to flow THE GREATER VISCOSITY, THE GREATER RESISTANCE TO FLOW VOLCANIC HAZARDS  LAVA FLOW are rivers of glowing molten rock or lava moving downslope or away from an eruption vent TWO TYPES OF LAVA FLOW  aa A rough, jagged, and is dangerous due to its sharp edges.  pahoehoe A lava flow which exhibits smooth-surfaced characteristics. TEPHRA OR ASH FALL PYROCLASTIC FLOW LATERAL BLASTS VOLCANIC GAS LAHAR 71 72 73 LEARNING OBJECTIVES Illustrate how energy from volcanoes may be tapped for human use LEARNING OBJECTIVES Cite the advantages and the disadvantages in harnessing energy from volcanoes. Non renewables/contributes to increase of green house gas in the atmosphere Convection Zone Layers of the Earth Geothermal Power Plants If you were to dig a That's because the big hole straight inside of the Earth is down into the Earth, full of heat. This heat you would notice the is called geothermal temperature getting energy. warmer the deeper you go. Convection Zone Layers of the Earth Geothermal Power Plants  Deeply drilled wells that extract hot water or steam from underground geothermal reservoirs PRODUCTION WELL  The primary energy source in many geothermal power plants. STEAM A rotating machine that converts the TURBINE kinetic energy of the steam into mechanical energy. Converts the mechanical energy GENERATOR from the turbine into electrical energy. Cools the condensed steam (water) after it has passed through the turbine. COOLING TOWER Used to return the cooled water (or brine) back into the geothermal reservoir, maintaining reservoir pressure and minimizing environmental impact. INJECTION WELL Carries the generated electricity from the power plant to the grid for distribution to consumers. TRANSMISSION LINES  Deep inside Earth, we can get a good source of energy. In the same way, deep down someone’s heart is kindness and love. That’s why we must always look for what is “invisible to the eye.” 98 99 Table of 01 What is a volcano? contents 02 How are volcanoes formed? 03 Features of volcanoes 04 Types of volcanoes 05 Volcanic eruptions 06 The most famous volcanoes Table of 01 What is a volcano? contents 02 How are volcanoes formed? 03 Features of volcanoes 04 Types of volcanoes 05 Volcanic eruptions 06 The most famous volcanoes