Fluent Essays

check attach Find an event that occurred this week that moves you. You must be able to relate it to the current chapter in some way – creativity is welcome. For instance, let’s say you read about the war in Afghanistan and parts of Pakistan. After reading the article, you check a world map and find that some remote parts of Pakistan are near the Himalayan Mountain Range. You will discover in Chapter 3 that the Himalayas were formed by a convergence of two continental plates, the Indian plate and the Eurasian plate, which causes a convergence zone that resulted in mountain uplift. And, voila!, the Himalayans are formed. Remember, geology is all about connections. The physical environment always sets the context for human events, and, often, they have a more direct influence than you may initially imagine. For example, you’re not worried about a tsunami if you live in North Dakota, but you are much more aware of the Pleistocene glaciations than you would be if you lived in Arizona. You may use an article from the following sources: Reuters National Public Radio Another news outlet if you include a paragraph telling me why you chose it. Turn in: A document that includes the entire story (copy and pasted from the original site). The citation (where you got it and when). The link. A map of the location of the event that was not included in the article. Paragraph of what you think about the news (good, bad, indifferent – just tell me why). Paragraph explaining at least one geologic connection that relates to this week’s chapter. Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Cosmology  Conscious thought distinguishes humans.  Developed across 1,000s of generations.  Lends us curiosity, insight, and the ability to learn.  As a result, we seek to explain our surroundings.  Where do we come from?  Where do we fit in the Universe?  Why are we here? Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Cosmology  Study of the structure and history of the Universe.  Cosmology is a complicated science.  Requires thinking in unfamiliar scales of space and time. Spatial scales. Attometers (10-21 meters), to 10s of billions of light years (9.4622 meters +). Temporal scales. Attoseconds (10-21 seconds), to 10s of billions of years (3.1517 seconds +). Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth’s Changing Place  3,000 years ago, humans knew the heavens well.  They knew that stars were fixed relative to other stars.  They knew that stars moved predictably across the sky.  They saw retrograde motion separating planets from stars.  They did not think of Earth as a planet, however.  Movement in the heavens was attributed to deities. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context An Evolving Image of Earth  The ancients thought the Universe was geocentric.  Heavenly bodies circle around a motionless central Earth.  “Proven” by Ptolemy (100–170 B.C.), the idea was wrong.  The idea held as religious dogma for 1,400 years.  A heliocentric (sun-centered) universe was proposed by the Greeks ~ 250 B.C. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Renaissance  Rebirth of rational thought in 15th century Europe.  Spawned a new age of scientific discovery.  Copernicus – Published evidence for heliocentricity.  Kepler – His elliptical planetary orbits refuted Ptolemy.  Galileo – Observed moons orbiting Jupiter.  Newton – Planet motion explained by his Theory of Gravity.  Natural laws governed natural events.  Geocentricity faded away. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Solar System  Solar system: A sun, planets, moons and other objects.  Earth shares the solar system with 7 planets. A planet…  Is a large solid body orbiting a star (the Sun).  Has a nearly spherical shape.  Has cleared it’s neighborhood of other objects.  Moon – A solid body locked in orbit around a planet.  The solar system also includes asteroids and comets. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The PlanetsThe Planets  Two groups of planets occur in the solar system.  Terrestrial (Earthlike) – Small, dense, rocky planets. Mercury, Venus, Earth, and Mars.  Jovian (Jupiter-like) – Large, low density, gas-giant planets. Jupiter, Saturn, Uranus, and Neptune.  Pluto is no longer considered to be a planet.  Two groups of planets occur in the solar system.  Terrestrial (Earthlike) – Small, dense, rocky planets. Mercury, Venus, Earth, and Mars.  Jovian (Jupiter-like) – Large, low density, gas-giant planets. Jupiter, Saturn, Uranus, and Neptune.  Pluto is no longer considered to be a planet. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Solar SystemThe Solar System  The Terrestrial planets are the 4 most interior.  The Jovian planets occupy the 4 outermost orbits.  The asteroid belt lies between Mars and Jupiter.  Planet orbital planes lie within 3o of the Sun's equator.  The Terrestrial planets are the 4 most interior.  The Jovian planets occupy the 4 outermost orbits.  The asteroid belt lies between Mars and Jupiter.  Planet orbital planes lie within 3o of the Sun's equator. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation  The Nebular Theory.  A 3rd, 4th or nth generation nebula forms ~4.56 Ga.  Hydrogen and Helium left over from the big bang.  Heavier elements produced by stellar nucleosynthesis.  This material coalesces into an accretion disc.  The Nebular Theory.  A 3rd, 4th or nth generation nebula forms ~4.56 Ga.  Hydrogen and Helium left over from the big bang.  Heavier elements produced by stellar nucleosynthesis.  This material coalesces into an accretion disc. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation  The ball at the center grows dense and hot.  Fusion reactions begin; the Sun is born.  Dust in the rings condenses into particles.  Particles coalesce to form planetesimals.  The ball at the center grows dense and hot.  Fusion reactions begin; the Sun is born.  Dust in the rings condenses into particles.  Particles coalesce to form planetesimals. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation  Planetesimals accumulate into a larger mass.  An irregularly-shaped proto-Earth develops. • The interior heats up and becomes soft. • Gravity shapes the Earth into a sphere. • The interior differentiates into a-Fe core and stony mantle.  Planetesimals accumulate into a larger mass.  An irregularly-shaped proto-Earth develops. • The interior heats up and becomes soft. • Gravity shapes the Earth into a sphere. • The interior differentiates into a-Fe core and stony mantle. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation  Soon, a small planetoid collides with Earth.  Debris forms a ring around the Earth.  The debris coalesces and forms the Moon. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation  The atmosphere develops from volcanic gases.  When the Earth becomes cool enough.  Moisture condenses and accumulates.  Comet bombardment adds more water.  The oceans are born.  The atmosphere develops from volcanic gases.  When the Earth becomes cool enough.  Moisture condenses and accumulates.  Comet bombardment adds more water.  The oceans are born. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Solar System FormationSolar System Formation Synopsis Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth  What would solar system visitors notice about Earth?  A magnetic field.  An atmosphere.  Surface features. Continents. Oceans. Polar ice caps. Evidence of humanity? Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Celestial Neighborhood  Interstellar space is a vacuum with scarce matter.  Matter greatly increases approaching the Sun.  The Sun ejects matter into space as the Solar Wind.  Solar Wind…  Magnetically charged particles.  Stream outward in all directions.  Consists of… Protons (+ charge). Electrons (– charge).  A small percentage of the Solar Wind hits Earth. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Magnetic Field  Like a bar magnet, Earth has a dipolar magnetic field.  Magnetic field lines flow from N to S and…  Extend into space and weaken with distance from Earth.  Create a shield around Earth (the magnetosphere). Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Van Allen BeltsThe Van Allen Belts  The solar wind is deflected by the magnetosphere.  Near Earth, the stronger magnetic field forms the Van Allen belts, which arrest deadly cosmic radiation. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Aurorae  Some ions escape Van Allen belts.  Pulled to the magnetic poles, the ions generate light.  Spectacular aurora follow solar flares.  Aurora borealis – Northern lights.  Aurora australis – Southern lights. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Atmosphere  Earth, with an atmosphere, is unique among the planets  Densest at sea-level, the atmosphere thins upward.  The atmosphere is mostly nitrogen (N2).  Oxygen was absent from the atmosphere before 2.5 Ga. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Atmosphere  99% of atmosphere is below 50 km.  The rest (1%) is between 50 and 500 km.  Sea-level atmospheric P = 14.7 psi. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Atmosphere  The atmosphere is layered.  Troposphere (0–11 km). Mixing layer. Weather is limited to this layer.  Tropopause (11–12 km).  Stratosphere (12–47 km).  Mesosphere (47– 81 km).  Thermosphere (> 81 km).  Boundaries between layers are termed “pauses.” Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Surface Features  Earth’s surface: continents are high; oceans are low.  Due to the differing buoyancy of each type of crust. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Elemental Composition  90% percent of Earth is comprised of 4 elements.  Iron (Fe) – 35%  Oxygen (O) – 30%  Silicon (Si) – 15%  Magnesium (Mg) – 10%  The remaining elements?  Form 10% of Earth. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth Materials  Organic chemicals – Carbon containing compounds.  Biological remains (wood, peat, lignite, coal, and oil).  Geologically rare (decompose in contact with oxygen).  Minerals – Inorganic crystalline solids.  Comprise rocks and, hence, most of the earth.  Most minerals on Earth are silicates (based on Si and O). Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth Materials  Glasses – Noncrystalline mineral-like matter.  Rocks – Aggregates of minerals. There are many types.  Igneous – Cooled from a liquid (melt)  Sedimentary – Debris cemented from preexisting rock.  Metamorphic – Rock altered by pressure and temperature.  Sediments – Accumulations of loose mineral grains. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth Materials  Metals – Solids made of metallic elements.  Melts – Rocks that have been heated to a liquid.  Magma – Molten rock beneath the surface.  Lava – Molten rock at the surface.  Volatiles – Materials that turn into gas at the surface.  H2O, CO2, CH4,and SO2,  Volatiles are released from volcanic eruption. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context A Layered Earth  We live on the thin outer skin of Earth.  Early perceptions about Earth’s interior were wrong.  Open caverns filled with magma, water, and air.  Furnaces and flames.  We now know that Earth is comprised of layers.  The Crust.  The Mantle.  The Core. Outer Core. Inner Core. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context A Layered Earth  Hard-boiled egg – Like an egg, Earth has 3 main layers.  Earthquakes – Seismic waves pass through Earth.  Seismic waves permit analysis of the interior. Wave velocity changes with density. Velocity changes give depth of layer changes. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth’s Interior Layers © W . W . Norton  Crust  Continental  Oceanic  Mantle  Upper  Lower  Core  Outer - Liquid  Inner – Solid Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Crust  The outermost “skin” of Earth with variable thickness.  Thickest under mountain ranges (70 km - 40 miles).  Thinnest under mid-ocean ridges (3 km – 2 miles).  The Mohorovicic discontinuity is the base of the crust.  The “Moho” separates the crust from the upper mantle.  Andrija Mohorovičić found this change in P-wave velocity. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Two Types of Crust  Continental crust – Granitic, underlies the continents.  Average rock density about 2.7 g/cm3.  Average thickness 35–40 km.  Oceanic crust – Basaltic, underlies the ocean basins.  Density about 3.0 g/cm3.  Avgerage thickness 7–10 km. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Earth’s Mantle  Solid rock layer between the crust and the core.  2,885 km thick, the mantle is 82% of Earth’s volume.  Mantle composition is the ultramafic rock peridotite.  Below ~100–150 km, the rock is hot enough to flow.  It convects: Hot mantle rises, cold mantle sinks.  Three subdivisions: Upper, transitional, and lower. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context The Core  Outer core Liquid iron-nickel-sulfur 2255 km thick. Density – 10-12 g/cm3  Inner core Solid iron-nickel alloy. Radius of 1220 km. Density – 13 g/cm3.  An iron-rich sphere with a radius of 3,471 km.  2 components with differing seismic wave behavior.  Flow in the outer core generates the magnetic field. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Lithosphere–Asthenosphere  Lithosphere – The outermost 100–150 km of Earth.  Nonflowing, rigid material that moves as tectonic plates.  Made of 2 components: Crust and upper mantle.  Asthenosphere – Upper mantle below lithosphere.  Shallow under oceans; deep under continents.  Flows as a soft solid. Edited by Joao Santos Essentials of Geology, 3rd edition, by Stephen MarshakEssentials of Geology, 3rd edition, by Stephen Marshak Chapter 1: The Earth in ContextChapter 1: The Earth in Context Next Chapter Chapter 3 Plate Tectonics Edited by Joao Santos