Volcanic and seismic events describe the activity of volcanoes and earthquakes, that can be recorded and used alongside other data to further enhance our understanding of plate tectonics. This process is the large scale motion of the Earth’s lithosphere; crust that is split into large sections known as tectonic plates move relative to one another, and can converge, diverge and subduct. This causes the formation of volcanoes, and triggers earthquakes of both large and small magnitudes. Recently, we have witnessed the effects of a major earthquake in central Italy. Seismologists and geologists are now using data from the quake, measuring 6.2 on the Richter Scale, to continuously expand their knowledge of plate tectonics and the importance of …show more content…
Mapping the location of seismic events shows that they occur at plate boundaries and fault lines. It is clear that they happen here due to the activity of the tectonic plates; the shaking being caused by the release of energy, and the creation of seismic waves, due to the build-up of pressure. The recent earthquake in central Italy around the towns of Accumoli and Amatrice, is one of millions of seismic events that has enabled scientists to further explore the theory behind this activity. Not only will it allow us to better understand how and why these earthquakes occur, it will ensure we are better prepared in the future and that the amount of damage will be reduced. In the past 100 years, we have experienced over 10,000 strong earthquakes. When recording these on a world map, a positive correlation is clear between plate boundaries and seismicity. Many also appear to occur in clusters around certain areas of plate boundaries, further strengthening the belief that seismicity is another major piece of evidence. It is important to understand that earthquakes can sometimes occur not as a result of tectonic movement, which may be important to consider. For example, fracking for oil and gas production processes within the earth’s crust can trigger relatively minor earthquakes, or volcanic activity can lead to harmonic tremors. Despite this, it is clear that enough evidence supports …show more content…
Since 1596, when Abraham Ortelius suggested that they may ‘drift’, there had been great speculation around the issue. However, following Wegener’s theory, geologists such as Arthur Holmes were able to further develop these ideas, leading to the acceptance of the plate tectonics theory. The evidence that Wegener provided for his theory, was also useful evidence in proving that the plate tectonics theory is valid. Firstly, Wegener noticed that continents such as Africa and South America were able to fit together like a jigsaw puzzle. He also observed that animals and fossils in widely separated lands were similar. For example, remains of mesosaurus and cynognathus were found only in South Africa and South America. Therefore, the plates that these two countries lie upon must have moved apart over time; this will have been due to the tectonic movement of the continental
Earthquakes are best described as a shaking or vibration of the ground caused by breaking of rock. Sometimes they are very strong and other times you would hardly notice them. This shaking occurs when stress that builds up in the crust is suddenly released as the crust breaks free and/or slides against the other pieces of crust. Earthquakes may also be thought of as the breaking of a popsicle stick by applying pressure to both ends at the same time. Should you try this experiment , you will feel the pressure build up as you apply more force until the stick snaps. When the stick snaps you will feel an instant of pain at your fingers as the stress reduces and energy waves move throughout the stick. When the earth's crust is placed under similar types of stress, binding as the stress builds, it will also snap and release the energy into the surrounding rocks, 'ooch'. Thinking about earthquakes will become more clear if you try another experiment.
Earthquakes play a major role into understanding the composition and materials that exist within the Earth (Merali and Skinner, 2009, p.252). Earthquakes are the main source of insight into the inner workings of the earth, due to the nature of the seismic waves they produce. P and S waves are reflected and refracted at different boundaries within the earth, and this enables seismologists to make inferences about the internal composition and structural of planet Earth. (Merali and Skinner, 2009, p.252).
The west coast of the islands is on the edge of a continental shelf created by ancient volcanic movement (Broadhead 5) .This volcanic activity is due to plate tectonic movement which also created the numerous amounts of earthquakes on the island. Compared to the rest of British Columbia, Haida Gwaii has the most earthquake activity (Broadhead 5), the last of which being in a magnitude of 7.7 on t...
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
There are concerns that fracking could be the causation of earthquakes. In areas where fracking operations occur and earthquakes are not the norm, there has been instances of seismic activity. For example, before 2011, the last seismic activity experienced by small town in Ohio named Youngstown was in 1776, but in a span of months during 2011, more than 100 instances of seismic activity ranging from 2.7 to 3.9 on the Ric...
Since record keeping began, sometime in the 18th century, there have been 13 major earthquakes along the San Andreas Fault. However, radiocarbon dating has proved that earthquakes have been happening along the fault for thousands of years. The earliest recorded earthquake happened on July 28, 1769, and was experienced by Spanish explorer Gaspar de Portola while he camped along a small lake he named “San Andreas Lake”. Other notable early earthquakes occurred in 1836, 1838, 1865, 1868, and 1890. Unfortunately, there is no seismographic data recorded for these early earthquakes since it was not until 1887 that seismographs began being used in the United
The science of the natural disaster has baffled many, but from studying the San Francisco earthquake, scientists have made a number of important discoveries and they have a better understanding of earthquakes. At 5:12 on a fateful April morning in 1906, the mammoth Pacific and North American plates sheared at an incredible twenty-one feet along the San Andreas fault, surpassing the annual average of two inches (“San Francisco Earthquake of 1906”)(“The Great 1906 Earthquake and Fires”). The shearing caused a loud rumble in the Californian city of San Francisco. A few seconds later, the destructive earthquake occurred. The ground shifted at almost five feet per second, and the shaking could be felt all the way from southern Oregon to southern Los Angeles to central Nevada (“Quick”)(“The Great 1906 San Francisco Earthquake”). Moreover, the earthquake could be recorded on a seismograph in Capetown, South Africa, an astounding 10,236 miles away from San Francisco (“San Francisco ea...
From studying the science behind the San Francisco earthquake, scientists have made a number of important discoveries involving how earthquakes function. At 5:12 on a fateful April morning in 1906, the mammoth Pacific and North American plates sheared each other at an incredible twenty-one feet along the San Andreas fault, surpassing the annual average of two inches (“San Francisco Earthquake of 1906”) (“The Great 1906 Earthquake and Fires”). A few seconds later, the destructive earthquake occurred. The ground shifted at almost five feet per second, and the shaking could be felt all the way from southern Oregon to southern Los Angeles to central Nevada (“Quick”) (“The Great 1906 San Francisco Earthquake”). In fact, the earthquake could be registered in a seismograph on Capetown, South Africa, an astounding 10,236 miles away...
Before examining the Northridge event, understanding the naturally occurring hazard that is an earthquake will help to better understand exactly what happened and why it was such an important geological event. With four distinct layers, two layers, the crust and upper portion of the mantle, compose the skin that is the surface layer of the Earth. The crust is not a single, continuous piece. It is actually several different pieces, or plates, that come together to form the puzzle that comprises the surface of the Earth. These plates are in constant motion rubbing against one another. These areas, known as fault lines, where the plates rub up against one another have spots where one plate ”gets stuck while the rest of the plate keeps moving. When the plate has moved far enough, the edges unstick and is how most of the earthquakes around the world occur” (Wald, 2012). The energy stored from the friction of the two plate...
The plate tectonic theory was first proposed in 1915 by a man named Alfred Wegener, who was one of the first to identify that the continents of earth look like they fit together in a jig saw puzzle, but what separates him is the fact he suggested that the earth had separated over a period of time, introducing the future theory of plates. As Wegener had no explanation of why the earth's crust had separated many geologists turned against his ideas, these people were called anti-mobilists. The only evidence that was proved to help Wegener's theory was that palaeontologists had found fossils of similar species on different continents, which suggests that the same species were once on the same area of land with the only explanation being that they had been separated by the motion of land. As years passed more and more evidence was uncovered to support the idea of plates move constantly over time.
Since the beginning of human kind there has been a cloud of wonder of how our planet was formed. Scientist interested in this field through out the years have developed many different theories to how our planet came about. Before the Twentieth Century, scientists and geologists thought that mountain structures were due to the massive tightening of the earth caused by the gradual cooling of molten rocks. In 1900, American scientist Joseph Le Conte, published an article in the Appleton's Popular Scientific Monthly. He described that the problem in understanding mountain building was establishing the cause of sideways pressure. It was not until 1910, that an American Geologist named F.B.Taylor, proposed the idea of a continental drift. Other scientists dismissed Taylor's idea, because there was just not enough proof. However, Taylor's idea was then backed up by a German scientist named Alfred Wegener. He proposed that the continents surrounding the Atlantic Ocean, Africa and South America fit together like a jigsaw puzzle. His broad range of studies enabled him to incorporate his theory of Plate Tectonics. Wegener, later in 1915 while in the German military published his idea that interpreted how his continental drift theory worked. He proposed that a huge landmass called Pangea, meaning ("all land") existed 200 million years ago. He furthered explained that this super continent began to drift apart very slowly throughout millions of years into what it looks like now. Wegener went on several expeditions through out his life to the continents of South America and Africa.
The earth is split into four layers, inner and outer core, the mantle and crust. The top of the mantle and crust make up what is like the skin of our earth (see source 2). The skin is split up like a puzzle and we call these puzzle pieces’ tectonic plates (see source 1). These plates are constantly moving and the plate boundaries (edges of the plates) move and slide past one another. Sometimes as the plates move the plate boundaries become stuck. Pressure builds up in the stuck area over time and eventually breaks. This is why earthquakes occur due to the sudden movement of the plate sliding and breaking creating a fault line to go off. The fault line is the line on which the
Volcanoes are one of the most destructive forces on Earth. It is estimated that some 500 million people live near active volcanoes (Lutgens and Tarbuck, 2013). Of the Earth's known volcanoes, 70 are expected to erupt each year with at least one large eruption each decade (Lutgens & Tarbuck, 2013). As populations continue to increase and more people are attracted to the beauty surrounding these areas, the immediate threat to humans from these sometimes sleeping giants grows. Due to this, the study of volcanoes and the service that volcanologists provide to the public by way of information and predictions on activity is immeasurable.
Convergent boundaries, divergent boundaries and convection currents all examples of physical evidence that supports the theory of plate tectonics. Continental drift is the theory contrived by Alfred Wegener in 1912 that states that Earth’s tectonic plates are in slow constant movement. At the time he didn’t know how the continents moved. The theory was soon modernized in the 50’s and the theory of plate tectonics became was born. Plate tectonics is the theory that tectonic plates are in slow constant movement due to convection currents in the mantle. Now we know for sure, thanks to scientific studies of convergent boundaries, divergent boundaries, and convection currents in the Earth’s mantle, that the continental drift and plate tectonics theories are not
Earthquakes belong to the class of most disastrous natural hazards. They result in unexpected and tremendous earth movements. These movements results from dissemination of an enormous amount of intense energy in form of seismic waves which are detected by use of seismograms. The impact of earthquakes leaves behind several landmarks including: destruction of property, extensive disruption of services like sewer and water lines, loss of life, and causes instability in both economic and social components of the affected nation (Webcache 2).