* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download A. Shield volcanoes
Survey
Document related concepts
Transcript
English for Developing Teaching Science Course code: 1002408 Number of credits 3 (2-2-5) Category of the course : Specific course (compulsory) Dr. WORRAWAT PROMDEN Program of General Science, Faculty of Education, Buriram Rajabhat University , Lesson 3 English for Specific Purposes: Earth Science Earth science (also known as geoscience, the geosciences or the Earth sciences) is an all-embracing term for the sciences related the planet Earth. Fields of to study The following fields of science are generally categorized within the geosciences: • Geology • Physical geography • Geophysics • Soil science • Oceanography and hydrology • Glaciology • Atmospheric sciences Earth's spheres Earth science generally recognizes four spheres, the atmosphere, the lithosphere, the hydrosphere, and the biosphere; these correspond to air, rocks, water, and life, respectively. NASA. Photo taken by either Harrison Schmitt or Ron Evans (of the Apollo 17 crew). The Earth seen from Apollo 17 Atmosphere Earth's atmospheric gases scatter blue light more than other wavelengths, giving the Earth a blue 5 halo when seen from space. Troposphere The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 80% of the atmosphere's mass and 99% of its water vapor and aerosols. The troposphere begins at the surface and extends to between 9 km (30,000 ft) at the poles and 17 km (56,000 ft) at the equator. The average depth of the troposphere is approximately 17 km (11 mi) in the middle latitudes,with some variation due to weather. The temperature of the troposphere generally decreases as altitude increases. Temperatures decrease at middle latitudes from an average of 15°C at sea level to about -55°C at the top of the tropopause. Tropopause The tropopause is the atmospheric boundary betwe and the stratosphere. Most commercial aircraft are lower stratosphere, just above the tropopause, whe usually absent, as also are significant weather pertu Lithosphere The lithosphere is the rigid outermost shell of a rocky planet. On Earth, it comprises the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater. Depth (Km) 100 500 700 3000 5000 6300 Crust Continental CrustOceanic Crust 5-10Km 5-70 Km Lithosphere Upper mantle (Rigid) Transition zone (highly plastic) Asthenosph ere Mantle 2600(mildly plastic) Mesosphere Km Outer core 2200 Km (Molten) Inner core 1200 Km (Solid) 9 Hydrosphere The hydrosphere in physical geography describes the combined mass of water found on, under, and over the surface of a planet. The total mass of the Earth's hydrosphere is about 1.4 × 1018 tonnes, which is about 0.023% of the Earth's total mass. About 20 × 1018tonnes of this is in the Earth's atmosphere (the volume of one tonne of water is approximately 1 cubic meter). Approximately 75% of the Earth's surface, an area of some 361 million square kilometers (139.5 million square miles), is covered by ocean. The average salinity of the Earth's oceans is about 35 grams of salt per kilogram of sea water (3.5%) Biosphere The biosphere is the global sum of all ecosystems. It can also be called the zone of life on Earth, a closed (apart from solar and cosmic radiation), and self-regulating system. From the broadest biophysiological point of view, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, hydrosphere, and atmosphere. The biosphere is postulated to have evolved, beginning through a process of biogenesis or biopoesis, at least some 3.5 billion years ago. Plate tectonics 13 Plate Tectonic Theory Types of plate boundaries Diverge Transform fault Converge • Divergent boundaries • Convergent boundaries • Transform boundaries 14 Three types of plate boundary. Convergent Plate Boundary or Destructive Plate Boundary 1. Oceanic-Continental convergence 16 17 Subduction of the Nazca Plate beneath the South American Plate to form the Andes. 18 Subduction of the Nazca Plate beneath the South American Plate to form the Andes. 19 Convergent Plate Boundary or Destructive Plate Boundary 2. Oceanic-Oceanic convergence 20 21 Oceanic - Oceanic Convergent 22 The Mariana Arc and the Mariana Trench, where the Pacific Plate is subducting under the Phillipine Plate. 23 The Mariana Trench 24 Pacific Ring of Fire 25 Convergent Plate Boundary or Destructive Plate Boundary 3. Continental-Continental convergence 26 The collision between the Eurasian Plate and the Indian Plate that is forming the Himalayas 27 The collision between the Eurasian Plate and the Indian Plate that is forming the Himalayas 28 Divergent Plate Boundary 1. Continental – continental divergence 2. Oceanic - Oceanic divergence 29 Lake Malawi lies in a valley formed by the opening of the East African Rift, where the African tectonic plate is being split into two pieces. This is called a divergent plate tectonics boundary. Lake Malawi is Lake Malawi seen from orbitbetween 560 and Lake Malawi in Africa, photographed 580 kilometres long, by astronauts aboard the Space 30 The Red Sea Rift is a spreading center between two tectonic plates, the African Plate 31 Mid-Atlantic Ridge The average spreading rate for the ridge is 32 Transform fault or transform boundary or conservative plate boundary) 33 North American Plate The San Andreas Fault is a continental runs a length of miles (1,300 km) California in the The fault's motion is lateral strike-slip motion). It forms the boundary between Plate and the North Plate. Pacific Plate General Geology 4052101 34 Transform fault General Geology 4052101 Dr. WORRAWAT The San Andreas Fault on the Carrizo Plain in southern California 35 Volcano Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Author : ISS Crew Earth Observations experiment and the Image Science & Space Station, May 2006. 36 Volcanic activity Volcanoes can be described in terms of activity : still active and erupt frequently dormant (temporarily inactive but not fully extinct) extinct (never likely to erupt again) 37 38 Structure of Volcano 39 Structure of Volcano A volcano constitutes a vent, a pipe, a crater, and a cone. The vent is an opening at the Earth's surface. The pipe is a passageway in the volcano in which the magma rises through to the surface during an eruption. The crater is a bowl-shaped depression at the top of the volcano where volcanic materials like, ash, lava, and other pyroclastic materials are released. Solidified lava, ashes, and cinder form the cone. Layers of lava, alternate with layers of ash to build http://www.bing.com/images/search?q=pyroclastic flow#x0y5505 Pyroclastic Flows A pyroclastic flow is a mixture of hot steam, ash, rock and dust. 41 http://www.volcanodiscovery.com Lava Flows 42 Volcanic features 1. Stratovolcanoes or Composite Volcanoes 2. Shield Volcanoes 3. Tephra Cones or Cinder Cones or Scoria cone 4. Craters and Calderas A. Shield volcanoes B. Composite Cones slope < 15o andesitic lava/pyroclastic basalt debris Ex. Hawaii, Galapagos, steep near summit, gentler sides C. Cinder cones o slopes most violent angle of repose; 30o - 40 Arizona Ex. Fuji, Andes, Mt. St. Ex. cinder cone, northern 44 Ex. Mount Capulin, NE NewHelens Mexico 1. Stratovolcanoes or Composite Cone Volcano Lava Ash http://www.bbc.co.uk/schools/gcsebitesize/geography/natural_hazards/volcanoes_r ev3.shtml 45 • They are usually found at subduction zone, forming chains along plate tectonic boundaries where oceanic crust is drawn under continental crust or another oceanic plate. • The eruptions from these volcanoes may be a pyroclastic flow rather than a lava flow. A pyroclastic flow is a mixture of hot steam, ash, rock and dust. General Geology 4052101 Dr. WORRAWAT Characteristics of a Stratovolcanoes •(composite) Compositevolcano volcanoes are made up of alternating layers of lava and ash (other volcanoes just consist of lava). 46 http://en.wikipedia.org/wiki/Stratovolc ano Stratovolcanoes (composite volcanos) are common at subduction zones 47 Two famous stratovolcanoes are • Krakatoa, best known for its catastrophic eruption in 1883 and • Vesuvius, famous for its destruction of the towns Pompeii and Herculaneum in 79 A.D. An early 19th century illustration of Krakatau. The volcano exploded in 1883, killing 36,000 people . Eruption of Vesuvius in 1630 48 Volcanic activity at Anak Krakatau, 2008 49 http://en.wikipedia.org/wiki/Mount_Vesuvius A Map showing the cities and towns affected by the eruption of Mount Vesuvius in 79 AD. Pompeii and other cities affected by the eruption of Mount Vesuvius. The black cloud represents the general distribution of ash and cinder. 50 The casts of the corpses of a group of human victim of the 79 AD eruption of the Vesuvius, found in the so-called “Garden of the fugitives” in Pompeii. Photo taken by Lancevortex, 30 Jan, 2000 51 A Cast of a dog dead in the 79 AD eruption Author : Claus Ableiter 52 富士山 Fuji-san 53 General Geology 4052101 Dr. WORRAWAT Mount St. Helens, Washington 54 General Geology 4052101 Dr. WORRAWAT Mount St. Helens, Washington 55 General Geology 4052101 Dr. WORRAWAT 2. Shield Volcano 56 Mauna Loa is one of five volcanoes the Island of U.S. state of Pacific Ocean, and largest on Earth in volume and area is an active shield with a volume approximately http://en.wikipedia.org/wiki/Mauna_Loa57 http://en.wikipedia.org/wiki/Kohala_(mountain) Kohala volcano as seen from Mauna Kea The location of Kohala relative to the other volcanoes Shield volcano, Hotspot volcano 58 http://en.wikipedia.org/wiki/Mauna_Ke a A view of the Mauna Kea volcano of Hawaii from the ocean 59 3. Tephra Cones or Cinder Cone or Scoria cone http://en.wikipedia.org/wiki/Cinder_co ne A cinder cone or scoria cone is a steep conical hill of tephra (volcanic debris) that accumulates around and downwind from a volcanic vent 60 http://en.wikipedia.org/wiki/Capulin_Volcano_Na tional_Monument Capulin Mountain, Capulin Volcano National Monument, New Mexico. U.S. Geological Survey Photographic Library 61 4. เครเตอร ์และแคลดีรา (Craters and Calderas) A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption. They are sometimes confused with volcanic craters. The central cone group of Aso consists of five peaks: Mt. Neko, Mt. Taka, Mt. Naka, Mt. Eboshi, and Mt. Kishima. 62 The Aso caldera in Japan The steaming crater of Mt. Naka 63 阿蘇山 Aso-san Mount Aso is the largest active volcano in Japan, and is among the largest in the world. Aso has one of the largest calderas in the world (25 km northsouth and 18 km east-west). The caldera has a circumference of around 120 km (75 mi), 64 Kome Zuka (Scoria cone) lies in the vast Aso caldera 米塚 65 http://www.yado.co.jp/kankou/kumamoto/aso/komezuka/komezuka.htm 晩秋の米塚 [ばんしゅうのこめづか] Late autumn of Kome zuka 66 http://www.nps.gov/features/yell/tours/fountainpaint/hotspot_yell.htm 67 The Yellowstone caldera is the largest volcanic system in North America 68 Earthquake An earthquake (also known as a quake) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are measured using observations from seismometers. seismometers Zhang Heng, as Chinese astronomer, mathematician, geographer, cartographer, statesman and literary first seismoscope of world http://jeff560.tripod.com/stamps.html State Post Bureau of the People's Republic of China Seismoscope, Han Dynasty, 132 AD 70 http://www.stampcommunity.org/topic.asp?TOPIC_ID=21044&w The replica of Ancient Chinese Seismoscope http://granitestudio.org/2008/03/01/thehistorical-record-for-march-1-2008-zhanghengs-seismometer/ Chinese scientists and historians successfully built a working replica of 71 http://www.sciencephoto.com/media/3 Chinese earthquake detector, 64754/enlarge artwork V900/0161 Rights Managed Credit: GARY HINCKS/SCIENCE PHOTO LIBRARY 72 http://en.wikipedia.org/wiki/Seismometer Kinemetrics seismograph 73 www.edinformatics.com 74 http://www.ux1.eiu.edu/~cfjps/1300/magnitude.html The diagram below demonstrates how to use Richter's original method to measure a seismogram for a magnitude estimate in Southern California 75 The Richter magnitude scale is any of a number of ways to assign a single number to quantify the energy contained in an earthquake http://www.gg.uwyo.edu/ 76 Haiyuan Earthquake The disaster happened in the year 1920. According to Richter Magnitude Scale, the earthquake had a magnitude of 7.8, but then China claimed that it was 8.5. Whatever was the correct magnitude, it sure did kill thousands of people. Total casualty was reported as 200,000 in a summary published by the United States Geological http://en.wikipedia.org/wiki/1920_Haiy uan_earthquake Survey (USGS). 77