Geology Final Exam Flashcards
The _____ is thought to be a liquid, metallic region in the Earth’s interior.
outer core
What is the source of the energy that powers the Earth’s system?
The Sun & heat from the Earth’s interior
The asthenosphere is actually a part of the Earth’s_____.
mantle
Much of the original free oxygen in the atmosphere combined with iron dissolved in water to become iron oxide. True or False
True
Earth’s primitive atmosphere evolved from gases ________________
expelled from within
A ______ system is one in which energy moves freely in and out, but no matter enters or leaves the system.
closed
Which of the following energy sources is thought to drive the lateral motions of Earth’s lithospheric plates?
Export of heat from deep in the mantle to the top of the asthenosphere.
Bowen’s reaction series predics the sizes of the different mineral grains that grow from crystallizing magmas. True or False
False
Assimilation involves _________________
incorporation of the surrounding host rock into magma
Crystal settling involves
crystals sinking to the bottom of a magma chamber.
Olivine and quartz are commonly found together in the same igneous rock. True or False
False
Which of the following minerals is a silicate?
Feldspar
Pegmatites are composed of unusually tiny crystals. They are generally rich in diamonds. True or False
False
The west coast of South America is a ________ plate boundary?
Convergent
New oceanic crust and lithosphere are formed at
divergent boundaries by submarine eruptions and intrusions of basaltic magma.
Mount St. Helens and the other Cascade volcanoes are…….
young, active stratovolcanoes built on a continental margin above a sinking slab of oceanic lithosphere.
Which of the following statements apply to the asthensophere, but not the lithosphere?
Zone in the upper mantle that deforms by plastic flowage.
Deep ocean trenches are surficial evidence for…
sinking of oceanic lithosphere into the mantle at a subduction zone.
The modern-day Red Sea is explained by plate tectonics theory because it is a _______.
Rift Zone
The _____ _____ is a logical evolutionary analog of the African Rift Valleys ten million years from now.
Red Sea
Why is there no sea floor from over 180 million years?
Subduction
Where is the youngest sea floor?
Mid Ocean Ridge
_________ refers to the tendency of foundation material to lose its internal cohesion and fail mechanically during earthquake shaking.
Liquefaction
The Mercalli Scale is a scale from _____ to _____
I to XII
When an earthquake occurs energy radiates in all directions from its source. The source is also called ______
Focus
Approximately how much more energy is released in a 6.5 Richter magnitude earthquake than in one with magnitude 5.5?
30 times
Earthquakes near Memphis happen along a plate boundary.
False
The lithosphere is defined as ________
a ridgid layer of crustal and mantle material.
The mantle is composed mainly of metallic iron with small amounts of magnesium silicate minerals.
True
Continental crust is generally thicker than oceanic crust.
True
The asthenosphere is located in the ______ _______.
Upper Mantle
Assume that water filling a crack in a rock undergoes cycles of freezing and melting. Which of the following statements is true?
Water expands as it freezes, causing the crack walls to be pushed apart
Feldspars commonly decompose during weathering to clay materials, silica, and soluble constituents.
True
Sheeting is mainly a process of mechanical weathering.
True
According to most scientists, the universe was “born” more than __ ______ years ago.
13 billion
Igneous rocks solidify from ______ rock
Molten
The Marianas Trench - the deepest place in the ocean - is located at a _________ plate boundary.
convergent
As volcanic hazards go, “perhaps the greatest threat to life are _______ _______”.
pyroclastic flows
While attempting to service a GPS site in ______ _______ (UT), Dr. Abolins succeeded in getting a snowmobile stuck in the snow.
Wasatch Range
Since the 1811-1812 earthquakes, there have been no earthquakes with a magnitude of 6 or greater in the New Madrid Seismic Zone.
False
About fifteen years ago, the Richter scale replaced the Earthquake magnitude scale for most purposes. Today, the USGS commonly uses the Richter scale to communicate the “strength” or “size” of an earthquake to the public.
False
The slowest seismic wave is the _____ wave.
surface
Bangladesh is far from any tectonic plate boundaries, but earthquakes happen there anyways.
False
If you wanted to collect andesite samples, you would visit a ________ ______.
composite cone
The law of superposition states that younger features cut across older features.
False.
____ author of the first geology textbook.
Lyell
______ theory of plate tectonics
Wilson
The Paleozoic Era began ___ ______ years ago.
542 million