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Geology 104--Earth Science

Exam #1 Study Guide

Discuss three important characteristics of a scientific theory.  How do theories differ from hypotheses and laws in science? Briefly describe the "scientific method."  What distinguishes science from other fields of knowledge?

Compare and contrast the Ptolemaic and Copernican models of the solar system.  How do both of these models differ from Kepler’s model?

Discuss Kepler’s laws of planetary motion and how they relate to the details of Earth’s orbit around the sun.

Understand the scientific definitions of force, mass, velocity, and acceleration. Explain Newton’s four laws of motion and how they enable us to make sense of Earth’s orbit around the sun. 

Describe the nebular hypothesis. What evidence supports this hypothesis?  What accounts for the difference in composition between the inner, rocky planets (Mercury, Venus, Earth, Mars) and the outer “Jovian” planets (Jupiter, Saturn, Uranus, and Neptune)?

What are Earth's principal compositional layers?  How do these layers differ in terms of chemical composition and density?  How do continental and oceanic crust differ in terms of density and composition? What elements is each Earth layer enriched in? 

Summarize the theory of plate tectonics. Distinguish between the lithosphere and asthenosphere.  Be able to draw simple sketches of the three main types of plate boundaries, including subduction zones, collision zones, transform boundaries, and divergent boundaries.  Be able to summarize the evidence that supports the theory of plate tectonics.  What processes are thought to drive plate motions?

Discuss how plate tectonic theory enables us to explain various seafloor features, including mid-ocean ridges, transform faults, fracture zones, trenches, guyots, and passive/active continental margins.

Important Vocabulary (not exhaustive):

Discuss three important characteristics of a scientific theory. Briefly describe the "scientific method."  What distinguishes science from other fields of knowledge?

Describe the nebular hypothesis. What evidence supports this hypothesis?  What accounts for the difference in composition between the inner, rocky planets (Mercury, Venus, Earth, Mars) and the outer “Jovian” planets (Jupiter, Saturn, Uranus, and Neptune)?

What are Earth's principal compositional layers?  How do these layers differ in terms of chemical composition and density?  How do continental and oceanic crust differ in terms of density and composition? What elements is each Earth layer enriched in? 

Summarize the theory of plate tectonics. Distinguish between the lithosphere and asthenosphere.  Be able to draw simple sketches of the three main types of plate boundaries, including subduction zones, collision zones, transform boundaries, and divergent boundaries.  Be able to summarize the evidence that supports the theory of plate tectonics.  What processes are thought to drive plate motions?

What defining characteristics do all minerals possess? Understand the difference between silicate and non-silicate minerals. Know the basic chemical building block of the silicate minerals and how to draw this structure.  Understand the difference between ferromagnesian and non-ferromagnesian silicate minerals. 

How are igneous rocks classified? What textural feature distinguishes intrusive from extrusive igneous rocks?  Be able to describe the following common igneous rocks in terms of texture and composition: granite, rhyolite, diorite, andesite, gabbro, basalt.  Be able to discuss the plate tectonic settings where most igneous rocks are found. 

How are sedimentary rocks classified?  Be able to describe the common detrital, inorganic, and organic (biochemical) sedimentary rocks in terms of grain size (for detrital rocks) and composition (for chemical rocks).   

How are metamorphic rocks classified? Be able to distinguish foliated and non-foliated metamorphic rocks and be able to describe several examples of each.  In which plate tectonic settings do most metamorphic rocks form?  

Be able to draw out the rock cycle.  

Know the difference between an earthquake focus and epicenter.  Be able to describe the various types of seismic wave and the elastic deformation they cause.  Given a seismogram, be able to distinguish between P waves, S waves, and Surface waves.  Understand the difference between seismic wave amplitude (wave height) and period (time between successive wave crests).  What is the minimum number of seismogram records (each from a different location) needed to locate the source of an earthquake? For each increase of one point on the Richter scale, approximately how much more energy is released? 

What lines of indirect evidence give us information about Earth’s interior?  How do we know that the Earth’s interior is layered?  How do we know that the outer core is liquid?  How do we know that the mantle is solid?  Where does Earth’s magnetic field originate? Has Earth’s magnetic field always been oriented toward the present-day North Pole?  Explain. 

Important Vocabulary...