Volcanoes and earthquakes In the world, there are many natural disasters which occur without the human's contribution. Volcanoes and earthquakes are some disasters that have a huge impact on many things. These two types of natural events can compare or contrast to each other. These natural disasters have differences more than similarities. Volcanoes and earthquakes are different in three things: the geology, the process, and the effect.
These are boundaries where the plats move towards each other but 1 plate travels underneath (subduction). The less dense oceanic plate is the plate that subsides under the denser continental plate. The oceanic plate with melt as it falls to the asthenosphere creating a mantle plume where we expect to see a strombolian (cone) volcano. These volcanoes are typically tall cone shaped volcanoes. They are as such because they lava is andesitic/rhyolitic which means the lava contains 55%+ silica content.
Gas or its inability to escape is what causes volcanos to become violent. The longer gas is trapped, the more pressure builds up. The cause of gas building up is the result of the viscosity of the magma the gas is trapped in. Viscosity is the measure of the flow or how easily a liquid flows. If a liquid is viscous it is thick and will flow slowly like honey whereas a liquid that is nonviscous will flow like water.
How to predict an volcanic eruption Ground Deformation Ground deformation is the change in shape that happens before during or after a volcanic eruption. This happens because the sides of the volcano change shape because the magma in many ways to measure the change of shape of the volcano, like leveling, triangulation and more recently using continuous Global Positioning System (CGPS). It is also possible to use lakes as large tilt meters. Tilt meters measure the tiny degrees of tilt or slope on land. This is one of the oldest methods of knowing when ground deformation was caused because of rising lava.
Discuss the view that the impact of earthquake hazards depends primarily on human factors [40] An earthquake is a tremor or shockwave in the earth’s crust that is caused by the sudden movement of the crust, resulting in the earth shaking. Most earthquakes are a consequence of tectonic plate movement by tension causing a sudden release of energy or rubbing. These normally occur at plate margins or along fault lines and can cause hazards which need to be prevented where possible. Earthquakes can therefore occur at all plate boundaries, destructive, constructive and conservative but the most damaging tend to happen at destructive margins where the earthquakes have a high magnitude due to the rubbing of the oceanic and continental crusts. A hazard is a natural event that has the potential to effect both life and property.
The actual speed of P and S seismic waves depends on the density and elastic properties of the rocks and soil through which they pass. In most earthquakes, the P waves are felt first. The effect is similar to a sonic boom that bumps and rattles windows. Some seconds later, the S waves arrive with their up-and-down and side-to-side motion, shaking the ground surface vertically and horizontally. This is the wave motion that is so damaging to structures.
J. Subbiondo © 2004The CrustThe outer layer of the Earth is called the crust. It is made up of rock that floated to the surface when the Earth was formed. It is not a continuous layer, but is made up of large masses called tectonic plates.These plates drift slowly across the Earth's surface (tectonic means moving).The movement of these plates creates mountains and valleys.At weak points in the crust, it causes volcanic eruptions. And when plates bump into each other, earthquakes occur -- emitting shock waves or vibrations called seismic waves. The crust is the Earth's coldest layer.
The red colour shows basalt or whin sill. This rock is a hard igneous rock. An igneous rock is a rock formed by the result of volcanic eruption, basalt is a form of igneous rock caused by lava cooling quickly. The only reason why the waterfall is here is because of this rock. Without this rock the waterfall would not have occurred because there would have only been a less resistant rock type meaning that a waterfall wouldn’t be able to hold itself from erosion.
Examples of regional metamorphic rocks include schist and gneiss. Thermal metamorphic rocks, also known as contact metamorphic rocks, are formed by extreme heat along with quite a bit of pressure. The pressure pushes the molten rock against the Earth's surface, causing it to recrystallize. Examples of thermal metamorphic rocks are marble and sandstone
The point on the Earth's surface directly above the hypocenter is called the epicenter of the earthquake. The closer you are to the epicenter of the earthquake, the more dangerous and devastating. The severity of an earthquake can be expressed in terms of both intensity and magnitude. Although the two terms are very different, they are often confused with each other. Intensity is based on the observed effects taken place during the earthquake, for instance the ground shaking underneath people, buildings, and natural features.