Chapter2_post - Outline Sources of energy in natural...

Info iconThis preview shows pages 1–14. Sign up to view the full content.

View Full Document Right Arrow Icon
Outline Sources of energy in natural hazards Internal External Formation of the Solar System and Earth. Sources of heat energy inside the Earth Primordial Radioactive Internal structure of the Earth Density variations: core, mantle, crust Types of crust: oceanic, continental Strength variations: lithosphere, asthenosphere Lithospheric plates and mantle convection Plate tectonics Seafloor spreading Subduction Development of the theory of plate tectonics Types of plate boundaries and associated earthquakes Convergent – large earthquakes Transform – medium/large earthquakes Divergent – smaller earthquakes
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
What is a natural disaster? Naturally occurring event that causes devastation to humans or human property Foreseeable (though not predictable) part of plate tectonic cycle or hydrologic cycle Unusually large, severe or prolonged event Localized concentration of energy
Background image of page 2
Energy Sources of Disasters Internal : Release of Earth’s Heat – Plate Tectonics Formation of continents, oceans and atmosphere over long time scales , and continual release of energy as earthquakes and volcanic eruptions External : 1. Sun’s Energy (combined with gravity) Together, drive winds, waves, currents, hydrologic cycle and various agents of erosion 2. Impact of Extraterrestrial Bodies Infrequent collisions of Earth with asteroids and comets can have global effects on life
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Origin of the Solar System
Background image of page 4
Hubble Telescope Images of Protoplanetary Disks (Solar Nebula)
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Gas, ice and rock fractions in primordial nebula Rock
Background image of page 6
Origin of the Solar System Greatest accumulation of matter at center of disk forms sun, with main constituents hydrogen (H) and helium (He), light elements Mercury, Venus, Earth, Mars • Inner planets close to sun lighter elements driven away by solar radiation rocky (terrestrial) planets Jupiter, Saturn, Uranus, Neptune, Pluto (?) • Outer planets far enough from sun and massive enough to retain lighter elements icy (gas) planets of H and He
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Formation of Earth during accretion planetary embryos form and sweep up smaller planetesimals - perhaps a few hundred embryos at most
Background image of page 8
Formation of Earth’s Moon near end of Solar System formation, only large bodies remain resulting in giant impacts - type that formed Moon giant impact energy commonly resulted in whole or nearly whole planet melting
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Earth begins to differentiate
Background image of page 10
Geologic History of the Earth, continued
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
An aside: how do we estimate the age of the Earth? …radiometric dating of minerals certain elements are radioactive, meaning they are unstable in their present form and slowly transform to other elements or isotopes we can measure the rate of “decay”, ie, decay rates for these elements are well established Find a rock, measure abundances of the element and its decay product, use the decay rate to figure out how much time has passed to produce the present-day abundance of the decay product
Background image of page 12
1. Primordial Heat
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 14
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 66

Chapter2_post - Outline Sources of energy in natural...

This preview shows document pages 1 - 14. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online