physical Geology
________________________________ are atoms with the same atomic number but different mass numbers.
isotopes
________________ is thick (30 - 75 km), old (up to 4,400,000,000 years), composed of felsic (granitic) silicates, light (~2.7 g/cm3), and is highly deformed by folding.
Continental crust
The lithosphere is made up of the upper-most mantle and the
Crust
Which is the oldest eon?
Hadean
Which geoscientist was the first to introduce the idea of geological (or deep) time?
James Hutton
Which is the thinnest physical (mechanical) layer of the Earth?
Lithosphere
In which layer of the Earth does the convection necessary for plate motion occur?
Mantle
What property of the crust allowed it to form as the exterior of Earth?
Materials that make up the crust are less dense and rose to the top
Approximately how old is the oldest oceanic crust?
180,000,000 years
Atoms of AA decay to atoms of BB with a half-life of 100,000 years. If there are 20,000 atoms of AA to begin with (and 0 atoms of BB), how long will it take for there to be 2,500 atoms of AA?
300,000 years
How old is the Earth?
4,600,000,000 years
Which scientist developed the Continental Drift hypothesis?
Alfred Wegener
The Phanerozoic eon is divided into three eras. Which of the following is NOT one of those eras?
Neogene
Which type of convergence will result in a continental volcanic arc?
Oceanic-Continental
The supercontinent in the Continental Drift hypothesis was called ___________
Pangea
Which would generally NOT be involved in determining the relative age of rock strata?
Radioactive decay
What statement best describes the difference between a rock and a mineral?
Rocks are aggregates of minerals.
The number of protons in the nucleus, which is characteristic for a particular element, is that element's
atomic number
Which of the following radioactive isotopes is most useful for dating a very young sample (<20,000 years) of wood?
carbon-14
If you wanted to search for really, really old (i.e. billions of years old) rocks to date , would you go looking for continental rocks or oceanic rocks?
continental rocks
The kind of bonding characterized by the sharing of electrons is
covalent
When molten rock cools, minerals form. This is the process of:
crystallization
Order the divisions of geologic time from the longest to the shortest
eons, eras, periods, epochs
When did geologists develop the theory of plate tectonics?
in the 1960's
What scientific avenue of investigation gave scientists the best estimate of the age of the Earth?
radiometric dating
The principal of original horizontality states that ________ .
sediments are deposited as essentially horizontal layers
The thickness of ocean sediments that are close to a mid-ocean ridge is __________ the thickness of ocean sediments that are far from mid-ocean ridges.
less than
The most common element found in the Earth's crust is ___________, followed by ____________.
oxygen, silicon
__________________ are scratches or gouges cut into bedrock by glacial abrasion.
striations
This principle is often stated as "the present is the key to the pas
Uniformitarianism
George Geologist finds that unit F contains eroded pieces of unit G. Which of the following statements is true?
Unit G is older than unit F
13.82 billion years ago, the Big Bang created the _____________ from a point source.
Universe
Which of the following is a common mineral of the sulfide group?
Galena (PbS)
What element is diamond made of?
Carbon
What geologic era do you live in?
Cenozoic
A ________ is a geographic low marking the location where oceanic lithosphere descends into the mantle. Mid-Ocean Rift
Deep-Ocean Trench
Harry Hess' theory of __________ explained how ocean crust is generated and destroyed
Seafloor Spreading
What provides us with the most information about the interior of the Earth?
Seismic energy (earthquake) waves
What is the definition of the asthenosphere?
Solid, but "plastic" region of the upper mantle
At a ________, one colliding plate will be forced beneath another because of differences in density.
Subduction Zone
What happens when an oceanic plate converges with a continental plate?
The denser oceanic plate slides under the less dense continental plate.
If the temperature in the Earth generally increases with depth, how is it possible that the Inner Core is a solid?
The pressures in the core are immense and keep it in a solid state in spite of the temperature
What was the main reason the Continental Drift hypothesis was rejected?
The scientist who proposed it could not provide a mechanism for the movement of the continents
Who is credited with developing the principle of fossil succession?
William Smith
How will the age and temperature of the subducting plate affect its angle of descent?
Younger and warmer plates will have a shallow angle of descent
A nonconformity is _________ .
a gap in the geologic record bounded below by metamorphic or igneous rocks and bounded above by sedimentary rocks
What is the polarity of a magnetic field that has the same polarity as the present magnetic field?
a normal polarity
A disconformity is ___________ .
an erosional surface between horizontal sedimentary rocks
An atom that has gained or lost electrons is
an ion
The Red Sea is an example of:
initial rifting of a continent
The Hawaiian Islands are thought to have been formed at a ____________.
mantle plume/ hot spot
The study of fossil succession allows _________
matching of similarly-aged rocks from different outcrops
A divergent boundary is a boundary between two plates that __________.
move away from each other
All minerals are __________
naturally occurring
Divergent boundaries are places where:
new ocean lithosphere is created shallow earthquakes occur basaltic magma erupts
An undeformed sedimentary layer is __________ than the layer above and _______ than the layer below.
older --- younger
The only layer of the Earth that is a liquid is the
outer core
The most abundant compositional group of minerals in the Earth's crust is the _________________
silicates
The San Andreas Fault represents a:
transform boundary
Rocks close to mid-ocean ridges are __________ rocks far from mid-ocean ridges.
younger than