The Sierra Nevada Mountains on the Pacific coast of North America and the Andes on the coast of South America were cited. Wegener also suggested that India drifted northward into the Asian continent thus forming the Himalayas. Many other scientist provided evidence toward this theory of a “continental jigsaw”, this evidence included geological matches in the rock type on two different continents coastlines found thousands of miles away e.g. Scotland and Canada and South America and Africa. Fossil evidence was also provided; trilobites of the same species found in Canada and Scotland and also, coal deposits were located in Antarctica.
Wenger’s proposition was that the continents were slowly moving along with tectonic plates and that was why they shifted position on the earths surface, the evidence to support his theory was the same plant fossils and similar rock formations all found on different continents. Wenger believed that the continents had once formed to make one whole continent known as Pangea, which is Greek for ‘all the lands’. According to Wenger’s theory Pangea began to break up about 225-200 million years ago and eventually fragmented into the continents we know
Plate tectonics (also known as the conveyor belt principle) is a scientific theory that describes the large-scale motions of the Earth’s lithosphere, building on concepts from the theory of continental drift (movement of the Earth’s continents relative to each other). The lithosphere is broken up into 7 main tectonic plates which move from 0-100mm annually. It is thought that the continents once formed a single land mass called Pangea that drifted apart, this is the start of the main idea of plate tectonics. In 1596, Abraham Ortelius first made the speculation that continents might have ‘drifted’ but the concept was developed further by Alfred Wegener in 1912. Presently, Earth Scientists agree on the observation and assumption that the plates have moved with respect to one another, but they still debate as to how and when.
Theory of continental drift The hypothesis that the continents had once formed a single land mass before breaking apart and drifting to there present locations was first presented by Alfred Wenger. He believed that the continents were once joined in a super continent that scientists now call Pangaea. Over a vast period of time the continents drifted apart due to the earth’s rotation. In 1915 he published a book about his theory. His main evidence was the continents appear to have a jigsaw like fit, the west coast of Africa and South America have the same pattern of rock layers and have the same plant and animal fossils; some of these animals are only found in those parts of the world and their fossils show they could not swim.
Plate tectonics was first suggested as a theory by the geologist Alfred Wegener in 1915 when he proposed the concept of continental drift. Back in the geological past, what is now South America, Africa, Australasia and Antarctica fitted together into a supercontinent known as Gondwanaland; with North America, Europe and Asia fitting into another supercontinent known as Laurasia. (OCR AS/A2 Geology, Mugglestone et al, 2008). These were once believed to be joined to form one major central global landmass known as Pangaea (Introducing Geology, Graham Park). But now due to the global distribution of these major plates it has been proposed by Wegener and his successors that convection currents in the mantle are the cause of the movement of plates.
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.
The Era is made up of six Geologic periods, the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and the Permian. Much of the plants and animals that exististed and evolved was due to the climate and location of the continents. At the beginning of the Paleozoic period, the continents were far apart, but by the end they were close together and on the way in forming the supercontinent called Pangaea. The land was moving by Plate Tectonics. Four hundred and thirty million years ago there was glaciation; this caused an ice sheet to cover what is now North Africa.
The reason for the movement is convection currents originating in the core caused by radioactive decay. Knowing the theory of plate tectonics is a useful tool in understanding the distribution of earthquakes and volcanoes as they correlate very closely. If we map out the location of major earth quakes, location of active volcanoes and a map of general plat tectonic, the 3 would overlap. This gives us a general idea of locations and correlations. Each boundary between 2 plates have the capability of being a different type of boundary.
is quite late in the history of the Universe, which -- as we told you in our lastInstruction -- is thought to have begun about 15 million years ago with an almostunimaginable explosion called The Big Bang.At first, the Earth was just a ball of molten rock and gasses. As it began to cool,dense materials like iron sank down into its core. Lighter materials likecompounds of oxygen and water rose toward the surface.That's why the Earth is made up of different layers -- as you can see in this crosssection:There are three layers in the Earth: the Crust, the Mantle and the Core. For another way to look at them, click:http://mediatheek.thinkquest.nl/~ll125/en/fullstruct.htm -------------------------------------------------------------------------------- Page 2 www.etap.orgEarth Science Lesson 3Dynamic Earth Processes (Grades 8-12 )Instruction 3-1The Internal Structure of the Earth2 of 2California Content Standards Earth Science 3.b.B. J. Subbiondo © 2004The CrustThe outer layer of the Earth is called the crust.
Tectonic Plates:- The movement of Continental plates, furthermore renowned as Tectonic Plates, is renowned as “Tectonic Movement”. It is a technical theory that recounts the large-scale movement of Earth's lithosphere i.e. the outer layer of earth. Geologically, the outer layer of earth, which is also renowned as “Crust”, is divided into “lithosphere” and “Asthenosphere”. This is founded on dissimilarities in mechanical properties and in the procedure for the transfer of heat.