Science Reviewer 1st Quarter - PDF
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This document is a science reviewer covering plate tectonics, and includes information about seismic waves, types of crust, and mantle convection. It provides a basic overview.
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SCIENCE SCIENCE reviewer 1st Quarter ——————————————————————————— PLATE TECTONICS Seismograph - is an apparatus to measure and record vibration (Device), (lithospheric plates) massive irregular shaped...
SCIENCE SCIENCE reviewer 1st Quarter ——————————————————————————— PLATE TECTONICS Seismograph - is an apparatus to measure and record vibration (Device), (lithospheric plates) massive irregular shaped slab of solid rocks Seismogram - Result or the output > suggest that earths crust is made up of plates that. interact in various ways Seismometer - is the data or the main part of (earthquakes,mountains,volcano) seismograph. > lithosphere *crust & upper mantle* *100km thick* *less dense (float) Main Types of Waves: > asthenosphere *plastic below lithosphere* : Surface waves : Body waves TYPES OF CRUST/PLATE Body wave - is a seismic wave that moves > Oceanic Crust - Water or Sea Land, through the interior of the earth. Relatively thinner but denser than continental crust. (3.0 g/cm3) P waves or Primary waves - are the first > Continental Crust - Land, thicker but waves to arrive at a seismograph. less dense (2.7 g/cm Crust - It is the thickest part of the earth. It P waves are the fastest seismic waves is made of a variety of solid rocks like and can move through solid, liquid, or sedimentary, metamorphic, and igneous. gas. Earthquake - sudden and violent shaking of the ground. § waves or Secondary Waves - are seismic body waves meaning they travel Magnitude - is a measure of earthquake size through the Earth's interior. and remains unchanged with distance from the earthquake. S waves velocity is slower than that of Intensity - ground shaking af that location by P waves. considering the effects of the shaking on people Surface wave - is a seismic seismic wave Epicenter - part of the earth's surface directly that is trapped near the surface of the above the focus of an earthquake (point where the crust breaks). earth. Focus - Where the earthquake begins MAIN TYPES OF SURFACE WAVES Fault - a weak point in the tectonic plate :Love waves where pressure within the crust is release to last waves. :Rayleigh Waves Love waves - is a surface wave having Harry Hammond Hess - envisaged that oceans a horizontal motion that is transverse grew from their centres, with molten material (or perpendicular) to the direction the (basalt) oozing up from the Earth's mantle along wave is traveling. the mid ocean ridges. Rayleigh Waves - move the surface of Harry Hess and Robert Dietz 1960- They were the earth around in a circle, forward oceanographers who further developed the and down then back and up. idea that the seafioors were spreading. Triangulation method - can be used to locate an earthquake. Mid-Ocean Ridge - the undersea mountain Pacific Ring of fire, ring of Fire or Circum - chain where new ocean floor is produced: a pacific belt - is a region around much of the divergent plate boundary rim of the Pacific Ocean where many. volcanic eruptions and earthquakes. Sonar - a device that determines the distance of an object under water by recording echoes of 75% of Earth's volcanoes-more sound waves. than 450 volcanoes are located along the Ring of Fire. 90% of Earth's earthquakes occur along its MANTLE CONVECTION path. including the planet's most violent and dramatic seismic Density: Convection current is events. caused by differences in Seafloor Spreading temperature resulting to variation Seafloor Spreading- mechanism by It is a measure of how much mass which new oceanic lithosphere is there is in a volume of a substance. created at and moves away from divergent plate boundaries. Shows the amount of matter in a given space for a substance. Supporting ideas about the seafloor Scientists believe that she motion ol spreading theory: tectonic plates is caused by Convection Rocks are younger at the mid Currents ocean ridge. Rocks far from the mid ocean ridges Plates move siowly and continuously when the hot less dense material rises. are older. The rising hot material cools down in a Sediments are thinner at the ridges certain area. Rocks at the ocean floor are younger than those at the continents Volume - measures how much space a Ridge push happens when the substance occupies. lithosphere is pushed up by the Mass - measures the amount of matter in asthenosphere because of convection the substance. currents from the mantie. Hot molten materials in a convection cell rises near the mantle The mantle is the second inner layer of Earth, Slab pull (gravity): takes place when made up of mostly hot rocks and magma. It is a very hot layer because of the heat generated by subducting slab sinks into the hot mantle the core. because of a difference in temperature. The Core- The source of heat in mantle The rest of the plate to which the slab is convection current. attached to is being pulled in as well. Mantle convection - is a process by which thermal convection occurs in the inner layer of the earth. Subduction - is the process of one plate Plate Tectonic - The idea that Earth's moving under another plate. lithosphere is broken up into separate plates that float on the mantle. Plate Tectonic Theory was developed in 1960s, stating that the Earth's Tectonic plates ride on Asthenosphere lithosphere-the crust and the upper mantle- is broken up into several pieces called plates that The asthenosphere is a soft, less rigid move slowly. upper part of the mantle where the Subduction zone - The region in which one lithospheric plates float and move plate moves under another. around. Subduction zone is formed if one plate moves underneath the other. At the mid - ocean ridge - The region Convection currents - The motion of gas or liquid caused by differences in temperature. where old crust melted back into magma. A convection current is a heat transfer process that involves the movement of energy from one place to another. Ridge push - A driving force for plate motion at mid-ocean ridges as a result of the rigid lithosphere sliding down Primary Plates - (Pacific, North America, Orogenic belt - is a region of Eurasia, Africa, Indo-Australian, Antarcfica, deformed rocks. and South America) that make up the majority of the earth's surface and the Pacific Ocean. Subduction - is when the less denser Secondary Plates - Caribbean, the Cocos, the plate will go up and the denser plate will Juan de Fuca, the Nazca, the Philippines Sea, go down and the Scotia Subduction zone - is the place where two Oceanic Plates - plates below the ocean lithospheric plates come together, one Continental Plates - plates below a continent. riding over the other (overlapping). Types of Boundaries: Convergent (Collide) Subducton zone form when a Divergent (separation) continental crust and oceanic rust collide. Transform (Sliding) Oceanic - Oceanic Convergence - A Divergent plate boundaries - mostly happen boundary between the crusts is created - under the oceans. trench. Rift Valley - a vertical space that may extend deep down into the lowest layer of the crust is Trench - a long, narrow depression in the created as plates pull away from each other. ocean floor and a crack on the crust which is underwater. Isunamis may be Mantle Convection- is the very slow creeping formed. Earthquakes may happen. motion of Earth's solid silicate mantle as convection currents carrying heat from the Volcanic Island Arc. - series of voicanoes interior to the planet's surface. surrounded by water. These materials pile up near the tension zone forming mountain-like structures called At the mantle, the leading edge of the oceanic ridges. subducting plate melts and becomes fluid which turns into a hot molten material called Seatloor Spreading - is the filled-up space Magma. between the plates becomes a new seafloor. Mantle Plume - the column of rising magma Convergent Plate Boundary - It occurs when two plates slide towards each other and form Volcanic Arc - a group of volcanoes is formed either a SUBDUCTION ZONE (if one plate at the surface of the continental crust along the moves underneath the other) or an OROGENIC boundary where the two crusts converged. BELI (if the two simply collide and compress] transform fault plate boundary. - The plates slide Tsunami - a Japanese term for harbor against each other in opposite directions. No wave, This event is very dangerous mountains, frenches or volcanoes are produced. when it moves in land and destroys lives Processes and Landforms along with the and properties. convergence of plates Oceanic - Oceanic Collision Zone - occurs when two Oceanic - Continental continental crusts or plates converged Continental - Continental and could cause shallow earthquakes. Continental Drift Theory In Continental - Continental Convergence there is NO VOLCANOES Alfred Lothar Wegener proposed the theory of continental drift - the idea that Earth's continents move or ISUNAMIS may formed and happer!. 1910 - In this year Wegener stated his theory. The convergence will result in the 1960 - When continental drift finally became part of formation of a group of high landforms - mainstream science. Mountain Ranges. Brazil and Western Africa - First Expedition Density, - is the mass of an unit volume Wegener came up with his theory_by noticing the of a material substance. similarity in the coastlines of eastern South America and western Africa seemed to fit together, rather like liasaw. pieces. Granite - made in continental crust and has a low density. Brazil and western Africa - are places were in physical contact when the fossilized animals and plants were The granite and recycled material are alive. much lighter than the heavy basalt Fossil and geological evidence - are evidences that layers of the ocean plates Wegener found in Brazil and Western Africa. Greenland - Second Expedition Basalt - Made in oceanic crust and has a high density. His work on continental drift then suffered two interruptions: a second expedition to Greenland, followed by the outbreak of World War 1 - Wegener was Basalt is denser and heavier than conscripted into the German Army. the granite that makes up the continental plates. The Origin of Continents and Oceans.-while being in prison Wegener published his groundbreaking book. Pangaea In 1920, 1922 and 1929 Wegener published All Earth updated editions of Ihe Origin of Continents Super Continents and Oceans Just before the days of the dinosaurs the Earth's continents were all connected into He also added further evidence he had one huge landmass. gathered in Greenland, which showed that Panthalassa Greenland and North America were once This huge supercontinent was surrounded linked. by one gigantic ocean. Frank Bursley Taylor - An American geologist Super Ocean who had published evidences to support the THE EVOLUTION OF PANGEA idea of Continental Drift or Wegener's theory. Permian - Earth's crustal plates formed a single, massive continent Geological "Fit" Evidence - It is the matching of called Pangaea. large-scale geological features on different Period 250 - 300 million years ago illustration showing similar rock assemblages across different continents. Triassic - This era is popularly known as the "Age of Reptiles" The Appalachian Mountains of eastern North America linked with the This is the time when the Scottish Highlands. supercontinent was divided into two big continents. The familiar rock strata of the Karroo system of South Africa matched correctly with the Laurasia - Northern Continents Santa Cataring system in Brazil. Gondwang - Southern Continants Brazil and Ghana Mountain ranges agreeing over the Atlantic Ocean. Jurassic - was a golden time for dinosaurs. Glaciers carve- rocks and leave marks as they move Cretaceous - last period and ending. with the extinction of the dinosaurs Coal deposits- are found in sedimentary rock basins, where they appear as successive layers. Mesosaurus - is known to have been a type of Wegener's Evidences: reptile, similar to the modern crocodile: which propelled itself through the water with its long continental fit hind legs and limber tail. rocks fossils (Found solely in South Africa and Eastern Coal deposits South America.) Ancient climate Glaciers scars. Cynognathus - was a mammal-like reptile. Roaming the terrains during the Triassic period (250 to 240 million years ago), it was as large as South America and Africa - two a modem wolf. specific continents fit together most noticeably. Lystrosaurus - which translates to "shovel ceptile." is thought to have been a herbivore with a stout built like a pig. (Found in Antarctica, India, and South Africa) Glossopteris - the most important fossil evidence found in the plant found in Australia, Antarctica, India, South Africa, and South America-all the southern continents.) Glossopteris seed - is known to be large and bulky and possibly could not have drifted or flown across the oceans to a separate continent. Added Questions: Alfred Lothar Wegener - He was credited for the idea of Continental Drift Theory. Pangaea - All continents were once joined together forming a supercontinent Glossopteris - If is possibly the most important fossil plant avidence that continents are drifting.