Intrusive igneous rocks, also known as plutonic rocks, are formed inside earth's crust. Molten rock rises and fills openings or melts overlaying rocks. This eventually hardens creating an intrusive igneous rock. An extrusive igneous rock, or volcanic rock, is created by magma rising the earth's surface. Magma is known as lava when it reaches the surface.
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.
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.
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.
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.
Plate Tectonic Theory What is Plate Tectonics? Plate tectonics is the main force that shapes our planet’s surface over a long period of time the study of how the Earth's crust is shaped by geological forces. It relies on the understanding that the crust is divided into large pieces, or plates, that sit on the molten interior of the planet. Currents within the interior cause the plates to move, which causes many different geological events, including earthquakes and the forming of mountains and volcanoes. Understanding how plates move and interact is the main purpose of plate tectonics.
Earthquake shaking and damage is the result of three basic types of elastic waves. Two of the three propagate within a body of rock. The faster of these body waves is called the primary or P wave. Its motion is the same as that of a sound wave in that, as it spreads out, it alternately pushes (compresses) and pulls (dilates) the rock. These P waves are able to travel through both solid rock, such as granite mountains, and liquid material, such as volcanic magma or the water of the oceans.
Lava deltas are created when pahoehoe goes into the ocean and stays there for a long time. Lava deltas are fan shaped pieces of land that form in the ocean. When the lava flows into the ocean, it cools really quickly and breaks into pieces, which can be sand sized or block sized. The different pieces collect on a slope underwater and build the base of a structure that in time can hold up the lava flows that form the delta above the water. When the pieces of lava collect on a steep slope, then the side of the delta crumbles often and creates a bunch of submarine landslides.
Plate boundaries are routinely affiliated with geological events such as earthquakes and are responsible for geological enrichment by conceiving topographic characteristics such as hills, volcanoes, mid-ocean ridges, and oceanic trenches. Furthermore, the most of the world's active volcanoes happen along plate boundaries, with the Ring of Fire, situated on the Pacific Plate's being most active and most broadly known. Couples of examples of tectonic plates are African plate, Pacific plate and North American plate. The formation of all the continents is due to the movement of the tectonic plates and they are still in shift with a variety of 10 to 40 mm/annum which is the most important aspect of the Tectonic Movement. Tectonic motion first began round three billion years ago and the tectonic plates of the world were first mapped in the second half of the twentieth years.
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.