Plate Tectonics There are two main ways scientists learn about Earth’s Interior. The first way is, of rock samples. Scientists use drills to get as close as they can to get to the center of the earth, they also looked at rocks that spat out of volcanos during a volcanic explosion. The second way is, because of seismic waves. They study how seismic waves travel through Earth, seismic waves are vibrations that travel through Earth carrying energy, released during an earthquake. Those were the two main ways how scientists learned about Earth’s interior. Crust, Mantle, and Core
There are three main layers on the Earth. The first is, the crust, the outer layer of Earth. It’s everywhere, on dry land and the ocean floor, however it’s
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The first, would be Land features. Alfred Wegener saw how the coal fields in North America and Europe lined up, he also realized that mountain ranges in North America and Africa lined up. The second, evidence he used were the fossils. There were three types of fossils he found the first was the glossopteris a fern like plant found in Africa, South America, Australia, India, and Antarctica. The second and third were the Mesosaurus and the Lystrosaurus fossils, they were freshwater reptile fossils on continents separated by oceans. The third evidence Alfred Wegener used was, the climate zones. Alfred Wegener looked at the past of the climates and he found scratches in rocks from glaciers in South Africa. Those were the three main evidences Alfred Wegener used to prove Continental Drift …show more content…
One evidence of this theory is molten material. Molten Material is magma erupting from mid-ocean ridges. Alvin the submarine found weird rocks shaped like pillows or toothpaste. This tells us this magma cools quickly underwater. Another type of evidence are magnetic stripes. Magnetic stripes are patterns in the ocean floor to prove Earth’s magnetic field has reversed itself in history. Scientist also looked at the “magnetic memory” of the rocks. Scientist drilled pipes through water to drill holes into the ocean floor. Scientists discovered that the older rocks were further away and younger rocks were closer. Those were the three types of evidence that scientist used to support the theory of Sea Floor Spreading.
Plate Boundaries
There are three different types of plate boundaries. The first type of plate boundaries is, the spreading boundary. A spreading boundary is when two plates move apart. The spreading boundary is also known as a divergent boundary. The second type of plate boundary is a colliding boundary. A colliding boundary is when two plates come together, or collide. It is also known as convergent boundary. The third is, a sliding boundary. A sliding boundary is when two plates slip past each other moving in opposite directions. It is also known as transform boundary. Those were the three different types of plate
Plate tectonics is the theory that Earth's outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. Compared to the mantle, the plates are a hard, tough, and rigid shell. California is made up of different types of plates that are unique in the way that they form and move. (LiveScience)
The theory of plate tectonics states that the Earth’s lithosphere (top layer of the Earth’s crust) is split up into rigid sections called plates that are moving relative to one another as they move on top of the underlying semi-molten mantle. These plates are either continental, The North American Plate, or oceanic, The Nazca Plate.
But in fact these also proved plate tectonic theory because they showed temporal change ie they were once at plate boundaries but have moved away because of plate movement. All the evidence, sea floor spreading, hot spots and subduction proved the plates moved this knowledge then developed into the understanding that something must be providing energy or a current so that the plates could move; This theory then came about as ‘convection currents’. Convection currents is a liquid in the mantle that moves and the currents come from the subduction zones.
There are three distinct types of plate boundaries existing, which are supported by geological observation, geophysical data, and theoretical considerations. Their names and categories are based on if adjacent plates move apart from each other (divergent plate margins), toward one another (convergent plate margins), or slip past one another in a direction parallel to their common boundary (transform plate margins) (Pitman, W.C., 2007).
To support the theory of continental drift is through topography, surveying the floors of oceans, charts of rock magnetism, and statistics on rock ages (Trefil & Hazen, 2010). At one time scientist believed that the deep ocean floors were flat; accumulating the sediment that progressively wore away from the prehistoric landmasses (Trefil & Hazen, 2010). However, they discovered steep-walled valleys and elevated highlands. This was evidences that just as the continents are transformed and are active, so to is the seafloor (Trefil & Hazen, 2010). The Mid- Atlantic Ridge, positioned in the central part of the Atlantic Ocean, is recorded to be the longest mountain range on this planet. Volcanoes, lava flow, and earthquakes are a source of
The youngest oceanic crust is located along the mid-ocean ridges where new crust is formed when the old crust is pushed away from mid – ocean ridges as a result of the seafloor spreading.
Plate tectonics is the scientific theory that attempts to explain the movements of the Earth's lithosphere that have formed the landscape features we see across the globe today” (Briney). Geology defines “plate” as a large slab of solid rock, and “tectonics” is part of the Greek root word for “to build.” Together the words define how the Earth’s surface is built up of moving plates. The theory of plate tectonics dictates that individual plates, broken down into large and small sections of rock, form Earth’s lithosphere. These fragmented bodies of rock move along each other atop the Earth’s liquid lower mantle to create the plate boundaries that have shaped Earth’s landscape. Plate tectonics originated from meteorologist Alfred Wegener’s theory, developed in the early 20th century. In 1912, he realized that the east coast of South America and the west coast of Africa appeared to piece together like a jigsaw puzzle. He further examined the globe and deduced that all of Earth’s continents could somehow be assembled together and proposed the idea that the continents had once been linked in a single supercontinent called Pangaea. To explain today’s position of the continents, Wegener theorized that they began to drift apart approximately 300 million years ago. This theory
The fossils in the lower silty layers were most likely formed below water by normal geological processes. The sea level rose covering the organisms and the layers of silt settled above them. In the upper sandy layers the fossils could have been formed above water by a sudden catastrophic event as a result of ongoing erosive processes. The conditions in which the fossils formed were likely a result of wave action which eroded the coast line until it was unstable. When the sea level receded there was a landslide covering the
The solid part of the Earth consist of solid rocks and soil. The Earths surface is the geosphere. The hydrosphere makes up all of the water on Earth's surface. The Earth is divided into three layers the crust, mantle, and the core. The crust is very brittle and this is why it was easy for Mount St. Helen to blow it to pieces. Tectonic plates are what glides underneath the underlying asthenosphere. This is what causes mountains to shift or grow. This can affect when volcanoes erupt. Volcanos are located near tectonic plate boundaries, where plates either collide or separate.
Alfred Wegener was a meteorologist and astronomer. He was the first scientist to introduce the theory of the continental drift. Wegener theorized that at one time the continents were one large landmass or Pangaea that had drifted apart. His ideas were initially rejected by other scientists. It was not until long after Wegener’s death that proof was obtained and his theory verified.
Scientist who study the floor of the ocean are called geological oceanographers. The study the age, structure, and make of the ocean floor. In addition to this, they also study minerals, sediment, and marine fossils. Some of the tools they use, including drill rigs to uncover the floor, can cost up to $2 million. The also use tools that record seismic waves to study the formation of tsunamis and undersea earthquakes. Recently, geological oceanographers around the world have accepted the theory of plate tectonics. Geological oceanographers always have their master's degree. For those who were involved with research will have a PhD in addition to their master's. Advanced education in geological oceanography can prepare a person to make significant
Earth is in fact an intricate planet that has multiple layers of differing compositions. To be exact the earth has four main layers. The uppermost layer is the one humans come in most contact with, the crust. The crust consists of “thin silicate rock material”(Structure of the). Although the crust is not entirely the same. Actually there are two distinct types of crust, oceanic and continental. “The continental crust is made up of mostly rocks similar to granite while the oceanic crust is much denser and made up of a material similar to basalt”(Structure of the, Rose). The second layer is called the mantle. “The mantle is much denser than the crust and contains similar to the crust mostly solid silicate crust”(Structure of the). “As we travel further down the earth we wind up in the outer core. The outer core is a core of molten nickel and iron. Finally there’s the inner core. The inner is a solid metal core made up of nickel and iron”(Structure of the). All these layers functioning together cast out a magnetic
When collisions between plates occur, the crust is pushed up sometimes forming ranges of mountains. This is the way that most
Science is all about discovery, and learning why things happen. The world is full of mysteries and it takes a special person to desire to discover the answer to the world’s biggest mysteries. Scientists everywhere devote their time and energy to discovering information that will change how people view the Earth. One of the most important discoveries is how our continents were once together and how they divided.