Volcanoes Volcano: mountain that forms as lava flows through a crack onto Earth’s surface Magma: melted rock under the surface of the Earth Lava: Magma on Earth’s surface There are many natural hazards that result from plate tectonics and other things of the world. As we had stopped on Convergent Plate Boundaries, let’s start with the volcanoes. A volcano is a mountain that forms as lava flows through a crack on Earth’s surface. The lava, ash, rock, and hot gases that shoot out of volcanoes change the land and even the climate.

Three Types Of Volcanoes Composite Volcano Shield Volcano Cinder Cone Volcano Brief preview slide for what’s coming up on the next few slides.

Composite Volcano Composite Volcano: tall, steep, cone-shaped volcano made of layers of ash, rock, and lava. Explosive eruptions. Ex. Mt. Saint Helens in Washington State There are three types of volcanoes: composite volcanoes, shield volcanoes, and cinder cone volcanoes. Composite volcanoes are also known as stratovolcanoes. They are steep and cone-shaped, made of many layers of volcanic ash, lava, tephra (rock particles), and pumice. They erupt explosively and are most frequently located in the Ring of Fire in the Pacific. Examples are Mt. Saint Helens in Washington State, Mt. Shasta in California State, and Mt. Fuji in Japan.

Shield Volcano Shield Volcano: broad, dome-shaped volcano with gentle slopes. Erupts slowly. Ex. Mauna Loa in Hawaii State Shield volcanoes are broad, dome-shaped volcanoes with gentle slopes. They erupt slow and steadily. Many of the volcanoes found in Hawaii are shield volcanoes.

Cinder Cone Volcano Cinder Cone Volcano: small, steep, cone-shaped volcano. Explosive eruptions. Ex. Paricutin in Mexico Cinder cone volcanoes are also known as scoria cones. They are small, steep, and common around the world. They shoot rocks with their eruptions.

Natural Disasters and Solutions Natural Disaster: major adverse event resulting from natural processes of the Earth Ex. Volcanoes, Earthquakes, Tsunamis Need solutions to reduce impact and speed up recovery Teachers, ask what kind of other natural disasters the kids know of and whether they can remember any recent natural disasters that have occurred. (i.e. Hurricane Katrina, etc). Then ask them to brainstorm any solutions to natural disasters before showing the next three slides containing methods to predict or tools used for detection and preventative measures.

Solutions to Volcanoes Observing volcanic eruption history Satellite Seismograph drums Tiltmeters Volcanologists can predict future volcanic eruptions by observing past volcanic eruptions, setting up observatories near the volcanoes as they did at Hawaii. By picking through the remains of previous eruptions, scientists can map old lava flows, pyroclastic deposits, and other volcanic debris around the crater to reveal timing, type, direction, and magnitude of possible future blows. Satellite data helps scientists better observe volcanic fallout and gas concentrations around the volcano. They are also able to discern the effects of global warming on future volcanic eruptions Observing seismic activity is also important with how earthquakes can cause magma to move beneath volcanoes. Many computer-equipped monitoring systems observe the geophysical status quo within volcanoes through seismic networks among observatories. Tiltmeters and other surveying equipment allow scientists to determine how deep a magma source is, how fast it is moving, and where the eruption will appear on a volcano.