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© 2006 Pearson Prentice Hall
Lecture Outlines PowerPoint
Chapter 1
Earth Science 11e
Tarbuck/Lutgens
Earth Science, 11e
Introduction to Earth Science
Chapter 1
Earth Science
Encompasses all sciences that seek to understand • Earth • Earth's neighbors in space
Earth Science includes• Geology - literally the “study of Earth” • Oceanography – a study of the ocean
Earth Science
Earth Science includes• Meteorology - the study of the atmosphere
and the processes that produce weather • Astronomy - the study of the universe
People and the environment
Environment • Surrounds and influences organisms • Physical environment encompasses water,
air, soil, and rock• Term “environmental” is usually reserved
for those aspects that focus on the relationships between people and the natural environment
People and the environment
Resources • An important focus of the Earth sciences • Includes water, soil, minerals, and energy• Two broad categories
• Renewable – can be replenished (examples include plants and energy from water and wind)
• Nonrenewable – metals (examples include metals and fuels)
People and the environment
Population • Population of the planet is growing rapidly • Rate of mineral and energy usage has
climbed more rapidly than the overall growth of population
Environmental problems• Local, regional, and global
People and the environment
Environmental problems• Human-induced and accentuated
• Urban air pollution• Acid rain• Ozone depletion• Global warming
• Natural hazards • Earthquakes • Landslides
People and the environment
Environmental problems• Natural hazards continued
• Floods• Hurricanes
• World population pressures
Quiz Break Section 1
Scientific inquiry
Science assumes the natural world is • Consistent• Predictable
Goal of science • To discover patterns in nature• To use the knowledge to predict
Scientific inquiry An idea can become a
• Hypothesis (tentative or untested explanation) • Theory (tested and confirmed hypothesis) • Paradigm (a theory that explains a large number
of interrelated aspects of the natural world)
Scientific method • Gather facts through observation • Formulate hypotheses and theories
Scientific inquiry
Scientific knowledge is gained through • Following systematic steps
• Collecting facts• Developing a hypothesis • Conduct experiments • Re-examine the hypothesis and accept, modify,
or reject
• Theories that withstand examination • Totally unexpected occurrences
Early evolution of Earth
Origin of Earth • Most researchers believe that Earth and the
other planets formed at essentially the same time
• Nebular hypothesis • Solar system evolved from an enormous rotating
cloud called the solar nebula • Nebula was composed mostly of hydrogen and
helium
Early evolution of Earth
Origin of Earth • Nebular hypothesis continued
• About 5 billion years ago the nebula began to contract
• Assumes a flat, disk shape with the protosun (pre-Sun) at the center
• Inner planets begin to form from metallic and rocky clumps
• Larger outer planets began forming from fragments with a high percentage of ices
The Nebular hypothesis
Figure 1.7
Early evolution of Earth Formation of Earth’s layered structure
• As Earth formed, the decay of radioactive elements and heat from high-velocity impacts caused the temperature to increase
• Iron and nickel began to melt and sink toward the center
• Lighter rocky components floated outward, toward the surface
• Gaseous material escaped from Earth’s interior to produce the primitive atmosphere
Earth's “Spheres"
Hydrosphere • Ocean – the most prominent feature of the
hydrosphere • Nearly 71% of Earth's surface • About 97% of Earth's water
• Also includes fresh water found in streams, lakes, and glaciers, as well as that found underground
Earth's “Spheres"
Atmosphere • Thin, tenuous blanket of air • One half lies below 5.6 kilometers (3.5 miles)
Biosphere• Includes all life • Concentrated near the surface in a zone that
extends from the ocean floor upward for several kilometers into the atmosphere
Earth's “Spheres"
Solid Earth • Based on compositional differences, it
consists of the crust, mantle, and core• Divisions of the outer portion are based on
how materials behave • Lithosphere - rigid outer layer • Divisions of Earth’s surface - continents and
ocean basins
Quiz Break Section 2
Earth’s layered structureUsing the following:
V = 4/3 π r3
Ave. Crust thickness = ~30 Km
Upper mantle = 670 Km
What makes up the greatest volume of Earth?
a) Crustb) Upper mantlec) Lower mantled) Outer coree) Inner Core
Earth system science
Earth is a dynamic body with many separate but highly interacting parts or spheres
Earth system science studies Earth as a system composed of numerous parts, or subsystems
System - any size group of interacting parts that form a complex whole
Earth system science
System • Closed systems are self-contained (e.g. an
automobile cooling system) • Open systems - both energy and matter
flow into and out of the system (e.g. a river system)
Earth system science
Feedback mechanisms • Negative-feedback mechanisms resist
change and stabilize the system • Positive-feedback mechanisms enhance
the system
Earth as a system • Consists of a nearly endless array of
subsystems (e.g. hydrologic cycle, rock cycle)
Earth system cycles
Figure 1.17
Earth system science
Earth as a system • Sources of energy
• Sun – drives external processes such as weather, ocean circulation and erosional processes
• Earth’s interior – drives internal processes including volcanoes, earthquakes and mountain building
• Humans are part of the Earth system
Quiz Break Section 3
End of Chapter 1