Plate Tectonics ( 20 Points ) - 1678 Words

Question 1: Plate Tectonics (20 points) Plate tectonics is a theory where earth’s crust in the lithosphere is made up of plates that float on a hot layer of molten magma in the asthenosphere, and moves constantly and under different circumstances causes mountains, volcanoes, and earthquakes to appear. With the evidence of plate tectonics and fossils, it is believed that about 225 million years ago, all the major continents had formed one giant continent known as Pangaea. However, due to possible heat build up underneath the giant continent, Pangaea broke up thus splitting up populations of plants and animals. With the rift, ocean waters filled the areas that once were the giant continent, therefore separating these continents. To this day, landmasses continue to move apart, riding upon their respective plates. The movement of earth’s twelve major tectonic plates helped determine the position and shape of the continents for millions of years. Where the plates meet, and its motions determine the type of boundary. There are four types of boundaries where activity of plate tectonics can be found: divergent, convergent, collisional, and transform boundaries. A divergent boundary in plate tectonics is also known as a constructive boundary. It exists when two tectonic plates are moving away from each other and create rift valleys. This usually occurs between oceanic plates. The sea floor spreading is an example of divergent boundaries. An underwater chain of mountainsShow MoreRelatedThe Plate Tectonics Of New Zealand1581 Words   |  7 PagesStudy of the plate tectonics of New Zealand has been undertaken since the early 1800s, however the most notable discovery regarding the plate tectonic setting was made in the 1940s by Harold Wellman, who discovered the Alpine Fault. Since then, our knowledge of the plate tectonic setting of New Zealand has been vastly expanded, leading to our present day understanding of the topic. A large part of our present day knowledge of the plate tectonic setting has been gained through the study of activeRead MorePlate Tectonics and Crust Oceanic Lithosphere1542 Words   |  7 Pagescrust is 20 to 70 kilom eters thick and composed mainly of lighter granite. The density of continental crust is about 2.7 grams per cubic centimeter. It is thinnest in areas like the Rift Valleys of East Africa and in an area known as the Basin and Range Province in the western United States (centered in Nevada this area is about 1500 kilometers wide and runs about 4000 kilometers North/South). Continental crust is thickest beneath mountain ranges and extends into the mantle. Plate Tectonics * TheRead MoreThe Big Pine, Garlock, And San Andreas Fault929 Words   |  4 Pagesrequires such knowledge to effectively determine conditions at any given point in time. Tectonic Stress and the San Andreas Fault According to Townend and Zoback (2004) the San Andreas Fault (SAF) region has been noted for its possession of stress orientations in addition to the lack of a distinct heat flow anomaly at the trace of the fault. These findings indicate that there are average shear tractions that are less than 20-25 MPa in the seismogenic upper crust. Oftentimes, shear tractions measureRead MoreLab Lesson 2 Essay942 Words   |  4 PagesPart 1 of 1 - 100.0/ 100.0 Points Question 1 of 22 4.0/ 4.0 Points Who proposed that all of the present continents were once joined together in a single supercontinent called Pangaea? A.Alfred Wegener B.Charles Darwin C.Arthur Holmes D. Harry Hess Answer Key: A Question 2 of 22 4.0/ 4.0 Points The scientific community rejected the theory of plate tectonics because Alfred Wegener could NOT A.identify a mechanism to move the continents. B.disprove competing theoriesRead MoreU.s. Geological Survey Registered The Tohoku Earthquake1546 Words   |  7 Pagesearthquake is one that occurs in a subduction zone, an area where one of the earth’s tectonic plates sinks under another (Fig. 2). Although it takes hundreds of years for a megathrust earthquake to start, they are particularly devastating because they deform the ocean floor, resulting in a tsunami.4,5 A tsunami is a huge wave of water caused by vertical movements on the sea floor (Fig. 2).6 The movement of tectonic plates leads to an enormous displacement of water, creating a series of waves.6 As theseRead MoreEssay on EarthQuakes2694 Words   |  11 Pagesintroduced it was learned that many earthquakes are the result of sea floor spreading, but most are caused by volcanic eruptions and plate tectonics. The plate tectonic theory explains that the earth is made up of 20 different plates that are always moving slowly past each other. This action pulls and compacts the plates, creating intense forces that cause the plates to break. This, in turn, causes earthquakes. The energy released then travels along fault lines in seismic waves (World Book Encyclopedia)Read MoreEarth Is The Planet Of Earth1586 Words   |  7 Pageswith surface soils and sediments. In most areas it is about 20-55 miles thick, and is held together by tectonic plates. These plates span across the entire planet , and interact with each other forming geographical features like oceans, mountains, trenches and volcanoes. Before the dawn of mankind it is commonly accepted that entire planet encompassed one giant continent known scientifically as Pangea, but over time, earth’s tectonic plates retracted causing the modern day seven continents. AlfredRead MoreVolcanic and Seismic Events as Proof of Plate Tectonic Theory2670 Words   |  11 Pagesevidence towards proving that plate tectonics theory is valid. A seismic event is the transient motion and release of kinetic energy caused by sudden failure of the earths crust, usually felt as shaking or tremors in the rock mass. Seismic events range in size from barely perceptible tremors to major earthquakes. Volcanic events occur when there is a release of magma, gas and ash from the Earth’s crust. The entire outer surface of the planet is divided into these plate formations with approximatelyRead MoreUsing Paleomagnetic Data For The World s Landmasses Of The Late Triassic Early Jurassic1389 Words   |  6 PagesJurassic. This concept of a supercontinent was originally proposed by Alfred Wegener (Wegener, 1915). He suggested that all continents assembled into a single supercontinent, approximately 300 million years ago, and then according to the theory of plate tectonics, began to break apart 175 million years ago (Rogers et al., 2004) Immense geologic and geophysical evidence have been presented, by Wegener and others, to support this theory for the Late Triassic-Early Jurassic. However when analyzing the paleomagneticRead MoreThe Deaths of People in the Kobe Earthquake Essay1212 Words   |  5 PagesDeaths of People in the Kobe Earthquake As a class we have been asked to investigate Why did so many people die in the Kobe earthquake? In this project I will be covering: 1.Where, when and why the earthquake happened and which plates were involved. 2.What the primary and secondary effects were. 3.How well prepared the Japanese people were for the earthquake. 4.How well people coped with the disaster. 5.How the Japanese authorities put things right