Science Quarter One - Reviewer PDF
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This reviewer provides an overview of plate tectonics, including the theory, its discovery, and different types of plate movement. It also covers related topics like the structure of Earth's interior and earthquakes.
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SCIENCE QUARTER ONE - REVIEWER Plate Tectonics (1915): - is the theory that Earth's crust is broken up into plates - plates are constantly moving because of the convection current in the mantle (Convection Current in the Mantle: raising and falling of hot molten materials) - talks...
SCIENCE QUARTER ONE - REVIEWER Plate Tectonics (1915): - is the theory that Earth's crust is broken up into plates - plates are constantly moving because of the convection current in the mantle (Convection Current in the Mantle: raising and falling of hot molten materials) - talks about the movement of the plates HOW WAS PLATE TECTONIC THEORY DISCOVERED? Plate tectonic theory was discovered with the help of Alfred Wegener’s Continental Drift Theory Continental Drift Theory (1912): - Stating that continents are moving away/drifting from each other because of pole fleeing of the Earth - Proposed by Alfred Wegener - Rejected due to lack of evidences and the convection current in the mantle - States that the continents were once been joined by a supercontinent called Pangaea Pangaea - a supercontinent Panthalassa - a body of water surrounding Pangaea Tectonic Plates: - Also called as lithospheric plates - Massive, irregularly shaped slab of solid rocks THE 7 PRIMARY TECTONIC PLATES ON EARTH: (largest to smallest) 1. Pacific 2. North American 3. Antarctic 4. South-American 5. African 6. Eurasian 7. Indian Australian THE 7 SECONDARY PLATES ON EARTH: 1. Caribbean Plate 2. Nazca Plate 3. Cocos Plate 4. Scotia Plate 5. Arabian Plate 6. Philippine Plate 7. Juan de Fuca 3 TYPES OF PLATE MOVEMENT: SCIENCE QUARTER ONE - REVIEWER 1. Mantle Convection - describes the movement of the mantle as it transfers heat from the white-hot core to the brittle lithosphere 2. Slab Pull (Convergent Plate) - a force that results from denser oceanic plates sinking beneath less dense continental plates along convergent boundaries and subduction zones 3. Ridge Push (Divergent Plate) - the pushing force that plates experience as they slide down the raised asthenosphere underneath Mid Ocean Ridges. PLATE BOUNDARIES > are where two or more tectonic plates meet creating a geological features depending on the type of plate boundary and their interactions of tectonic plates > areas of increased geological activity 1. CONVERGENT PLATE BOUNDARIES (Destructive) - occurs when two tectonic plates move towards each other WHY IS IT CALLED DESTRUCTIVE? because of the collision of two plates leading to subduction;this is where earthquakes originate 2. DIVERGENT PLATE BOUNDARIES (Constructive) - occurs when two tectonic plates move away from each other WHY IS IT CALLED CONSTRUCTIVE? when they move apart, magma rises up in the gap 3. TRANSFORM PLATE BOUNDARIES (Conservative) - occur when two plates slide past each other horizontally WHY IS IT CALLED CONSERVATIVE? the crust is neither destroyed nor formed SCIENCE QUARTER ONE - REVIEWER Internal Structure of the Earth 2 Scientific Evidences of Earth’s Interior (Based on the Researchers) 1. Seismic Waves How did Seismic Waves lead to discovery of Earth's interior? - S-Waves can only travel through solids, which helped scientists understand the different layers within the Earth. 2. Rock Samples 3 Major Layers of Earth 1. Crust - 0.5% of Earth's Mass 2. Mantle - 80% of Earth's Mass 3. Core - Composed of the outer core and inner core, together making up about 15% of Earth's volume. The inner core is solid, while the outer core is liquid. As you go DEEPER, TEMPERATURE and PRESSURE increases - celsius temperature 1 DEGREE = 40 METERS Oceanic is YOUNGER than Continental Oceanic Rocks - basaltic and igneous -> Continental is older because it is rarely destroyed or recycled Ionian Sea and Mediterranean Sea: existing oceanic crust but still younger than continental - most of the rocks: oceanic & existing old rocks SCIENCE QUARTER ONE - REVIEWER Earthquake - produced by sudden release/snap off energy - shaking or trembling caused by release of energy - usually associated with faulting or breaking of rocks Where do Earthquakes occur and How often? 90% - Pacific Ring of Fire most of these result from convergent margin activity 15% occur in Mediterranean-Asiatic belt 5% occur in the interior of plates and on spreading ridge centers more than 150,000 earthquakes Top Countries Exposed to Volcanic & Seismic Activities: 1. indonesia 2. Japan 3. Philippines 4. Chile 5. Mexico 6. Kamchatka Peninsula 7. United States 8. New Zealand 9. Alaska 10. Canada Faulting - breaking of crust 1 CM - Movement per year NORMAL FAULT STRIKE-SLIP FAULT REVERSE FAULT - tensional - sheer - compressional - Divergent Plate - Transform Plate - Convergent Plate Boundary Boundary Boundary - shallow and low - shallow and high - deep and high magnitude magnitude magnitude SCIENCE QUARTER ONE - REVIEWER Elastic Rebound Theory - explains how energy was made and released during earthquake Proponent: Harry Fielding Reid (American Seismologist) - BASIS OF THIS STUDY: 1906 San Francisco Earthquake PROCESS OF ELASTIC REBOUND THEORY Friction -› Pressure -› Force -› Energy Chile Great Valdivian Notable Earthquake of 20th Century Lasted for 10 minutes Philippines Killer Luzon July 16, 1990 4:26 PM 7.8 Magnitude Epicenter: Nueva Ecija Seismic Waves SCIENCE QUARTER ONE - REVIEWER the shaking of the ground is caused by: ELASTIC STRAIN ENERGY (Stored Energy) CROSS SECTION OF AN EARTHQUAKE Hypocenter (HYPO): The point beneath the Earth's surface where the earthquake originates. Epicenter (EPI): The point on the Earth's surface directly above the hypocenter. SCIENCE QUARTER ONE - REVIEWER BODY WAVES Higher Frequencies and Lower Amplitude - (interior) mantle up through the core - higher frequency - arrives before the surface waves - speed is directly proportional to frequency - amplitude is inversely proportional to frequencies - stops traveling at the mantle PRIMARY WAVES SECONDARY WAVES - Compressional Waves - Shear Waves - fastest wave - perpendicular (up & down) - moves back and forth - slower than P-Waves - refracted - refracted: creates shadow REFRACTION - Slow Down and Bending of waves as they trav through layers of Earth. REFRACTED - Bended or Distorted SURFACE WAVES Lower Frequency and Higher Amplitude - traveling only through the crust - responsible for earthquakes RAYLEIGH WAVES LOVE WAVES - elliptical motion/circular - fastest s-wave - no transverse/perpendicular - horizontal motion - ripple up and down - shake from side-to-side - John William Strutt & Lord Rayleigh - named after: British mathematician (1855) Augustus Edward Hough Love. PLSR - PRIMARY, SECONDARY, LOVE AND RAYLEIGH SEISMOMETER is the INNER PART OF SEISMOGRAPH SEISMOGRAM - result and it records the motion of earthquake/any gram motion TRIANGULATION METHOD SCIENCE QUARTER ONE - REVIEWER - A technique used to determine the location of an earthquake's epicenter by using data from three or more seismic stations. - Three stations are the minimum required to accurately determine the epicenter, as fewer stations would provide insufficient data. Mohorovicic Discontinuity: boundary between the crust and the mantle discovered by: Andrija Mohorovicic in October 8, 1909 Project Moho (1958): project which aims to get a sample of earth's crust: - started 1958 - drilling started in 1960 - only stopped til the crust Conducted by: American Miscellaneous Society Discontinued due to: 1. political issues 2. budget issues 3. scientific issues Gutenberg Discontinuity: boundary between the mantle and core proposed by: Beno Gutenberg SCIENCE QUARTER ONE - REVIEWER Wadati Benioff Zone: seismological activities in the upper mantle while the lithosphere plate subducts or a planar zone of seismicity corresponding with the down-going slab in a subduction zone originates from: kiyoo WADATI (jp seimo) and hugo BENIOFF (american seismo) Hellhole (borehole) conducted by the USSR in order to compete/beat the US' project moho conducted in: Murmansk, Russia Project Moho was conducted in Guadalupe, Mexico SCIENCE QUARTER ONE - REVIEWER Continental Drift Theory Alfred Loathar Wegener - proposed the idea of continental drift (the idea that Earth's Continents move) HOW DID HE CAME UP WITH THIS THEORY? - by noticing the similarity in the coastline of Eastern South America and Western Africa seemed to fit together, rather like jigsaw puzzle THE EVOLUTION OF PANGAEA Pangaea - supercontinent surrounded by Panthalassa PERMIAN - Earth's crustal plates formed a single, massive continent called Pangaea Period: 250 - 300 Million Years Ago TRIASSIC - Popularly known as the "Age of Reptile" and this is the time where the supercontinent was divided into two: - Laurasia - North America, Europe and Asia - Gondwanaland - Australia, Antarctica, South Africa and America EVIDENCES OF CONTINENTAL DRIFT THEORY 1. Geological Fit Evidence - the matching of large-scale geological features on different illustrations showing similar rock assemblages across different continents - jigsaw puzzle 2. Climate Evidence - shows that glaciers moved from Africa towards the Atlantic Ocean and from Atlantic to South America - Glaciated Landscapes 3. Fossil Evidences - different kinds of fossils found in different areas CYNOGNATHUS, MESOSAURUS, LYSTROSAURUS AND GLOSSOPTERIS SCIENCE QUARTER ONE - REVIEWER CONTINENTS BEFORE PANGAEA: - Kenorland - Columbia - Rodinia - Panottia PAN - OLD GEO - EARTH SCIENCE QUARTER ONE - REVIEWER SEAFLOOR SPREADING - the process that continually adds new material to the ocean floor while pushing older rocks away from the ridge - inconsistent movement Mid-Ocean Ridge – the longest chain of mountains in the world---these are divergent plate boundaries. SEAFLOOR SPREADING - Harry Hess 1960 Sonar - a device that bounces sound waves off under-water objects and then records the echoes of these sound waves. The time it takes for the echo to arrive indicates the distance to the object. DRIVING MECHANISM: Convection Current in the Mantle FUEL: Magma SLOWLY SPREADING RIDGES RAPIDLY SPREADING RIDGES - tall, narrow underwater cliffs and - formations with low peek mountains - high peek EVIDENCES OF SEAFLOOR SPREADING: 1. Evidence from Molten Materials - rocks shaped like pillows show that molten material has erupted again and again from cracks along the mid-ocean ridge and cooled quickly - shape built because of the pressure 2. Evidence from Magnetic Stripes - rocks that make up the ocean floor lie in a pattern if magnetized stripes which hold a record of the reversals in Earth's magnetic field - normal and reverse formation of line - 100 - 300 years: magnetic reversal 3. Evidence from Drilling Samples SCIENCE QUARTER ONE - REVIEWER - core samples from the ocean floor shows that older rocks are found farther from the ridge while the younger rocks is located near the ridge