Geology final
Physical processes observed today (such as erosion and volcanic eruptions) have been active in the past and are responsible for the geologic history we see preserved in the rock record.
As understood by modern geologists, the principle of uniformitarianism implies that:
Ocean; trench
At converging plate boundaries, the plate containing ___________ crust subducts and forms a deep ocean _____________.
10%
At present, glaciers cover about ____ of the surface of continents.
Mountain glaciers
Cirques and horns are features associated with ______________.
Particle size
Clastic sedimentary rocks are subdivided according to __________________.
Rift valleys, Red Sea, Atlantic Ocean
Consider the modern Red Sea, Atlantic Ocean, and African Rift valleys. In which order, beginning with the earliest stage and ending with the most advanced, do they illustrate the evolutionary process of a divergent plate boundary?
Agree that continental drift occurs and the mechanisms that drive drift are at work in the ocean basins and upper crust, which were unknown in Wegener's time
Currently, most geologists _____________________.
The flow of the liquid outer core
Earth's magnetic field is generated by ___________________.
Earth's magnetic field
Earth's surface is protected from solar wind and cosmic radiation by _______________.
Brittle
Faults and earthquakes are examples of what type of behavior?
The percentage of pore space is high but the pore spaces are too small to transmit fluid. ?
How can a rock have high porosity and low permeability?
More mafic in composition
If a body of magma is subjected to fractional crystallization, the resulting magma will be ______________.
Original continuity
If two rock bodies on opposite sides of a canyon are identical, then they were likely physically connected at one time and formed part of an extensive, sheet-like layer of rock. This idea summarizes the principle of ________________.
Felsic
Igneous rocks that contain the first minerals to melt and consist mainly of feldspars and quartz are said to have a _____________ composition.
Supersposition
In an undisturbed sequence of sedimentary rocks, younger layers overlay older layers according to the principle of _____________.
200 million years
In an unweathered sample of igneous rock, the ratio of an unstable isotope to its stable daughter isotope is 6.25%. If no daughters were present at the time the rock cooled and solidified and the half life of the reaction is 50 million years, how old is the rock?
The Universe is considerably older than the Earth
In our current understanding of the Big Bang, _______________________.
Earth orbits around the sun
In the heliocentric model ______________________.
Cementation
Lithification is a process that involves burial, compaction, and _______________.
More viscous
Magma extruded at high temperature tend to be _________________.
Tend to be very viscous
Magmas with high silica content:
Mid ocean ridges
Magnetic anomalies in the sea floor are in belts that run parallel to __________________.
At an angle to prevailing winds as a result of the Coriolis effect
Major oceanic surface currents travel _______________.
Index minerals
Metamorphic minerals that form under a limited range of temperature and pressure and called ___________.
High; low ?
Metamorphism requires rocks to remain solid during all stages of transformation. Therefor, rocks containing mafic minerals metamorphose at ________________ temperatures, whicle rocks containing felsic minerals metamorphose at _____________ temperatures.
Experienced other climates in the geologic past.
Most regions that are now deserts have _______________________.
Overlies a subduction zone where continental and oceanic crust meet. ?
Mount St. Helens in Washington State:
U; V
Mountain valleys carved by glaciers tend to be shaped like the letter ______, whereas mountain valleys carved by water tend to be shaped like the letter _____.
Divergent; convergent
Normal faulting is most often associated with _________________ boundaries, while reverse faulting is most often associated with _____________________ boundaries.
Oceanic
Of these choices, which type of lithospheric plate is denser?
That S waves will not travel through the outer core and S waves will not travel through liquids; That pressure is higher in the outer core than inner core.
One important piece of evidence indicating that the Outer core is liquid is ______________.
Evaporates (salt)
Playas are places where you would expect to find abundant __________________ exposed at the surface.
The upper mantle and is a weak plastic layer
The asthenosphere is ___________________.
10,000
The current interglacial interval began a little more than _____________ years ago.
Sea floor spreading
The current theory of Plate Tectonics includes Wegener's Continental Drift Hypothesis and ___________ by Henry Hess.
Faults are fractures along which displacement has occurred; displacement does not occur along joints
The distinction between joints and faults is that _______________.
Bathymetry
The form and topography (depth profile) of the ocean floor is termed ______________.
Jupiter, Saturn, Uranus, Neptune
The gas-giant or Jovian planets are _______________.
In the subtropics, between 20 and 30 degrees north or south of the equator.
The most expansive hot deserts in Earth occur _____________________________.
Oceanic crust is more dense than continental crust
The ocean basins sit lower in the mantle than the continents because _____________.
Changed in the solid state
When rocks are metamorphosed, the mineral components of the rock are __________________.
a stream, a nearshore marine environment, and a desert
Which environment(s) will produce sediments with cross bedding?
Proterozoic
Which eon of geologic time represents the present?
Core
Which of Earth's layers has the greatest density?
The alignment of minerals or grains due to differential stress in metamorphism.
Which of the following best describes foliation?
The only common mineral composed entirely of silicon and oxygen.
Which of the following best describes quartz?
These rocks are made of only one composition.
Which of the following best describes why non foliated metamorphic rocks do not show foliation?
Water vapor, carbon dioxide, sulfur dioxide
Which of the following includes gases that are abundantly emitted by volcanoes?
Loss of volatiles to the atmosphere
Which of the following is NOT a process by which magma is formed within the crust?
Permeability
Which of the following is a measure of a material's ability to transmit water through interconnected pore space?
Ice, when it occurs naturally for example, glacial ice.
Which of the following is a mineral?
Features include a wide, gently sloping continental shelf that collects large volumes of sediment.
Which of the following is associated with passive continental margins?
Organic
Which of the following is not a requirement to be a mineral?
Silicates
Which of the following is the most common mineral group in Earth's crust?
Clay
Which of the following is the smallest?
Cold temperature; high salinity
Which of the following ocean waters would be the densest?
Contains one silicon atom and four oxygen atoms.
Which of the following statements about the silicate tetrahedron is true?
Sandstone
Which of the following will most likely form an aquifer?
Mountains stand high because they are gravitationally balanced by their deep crustal roots.
Which of these properly illustrate the principle of isostacy?
They rocks may be different sizes.
Why can two igneous rocks have the same chemical composition and different names?
On the inner banks building a point bar.
Within a meander, where is sediment most likely to be deposited?
along mid-ocean ridges
Within the sea floor, the rate of heat flow is greatest ______________.
Shortening
A body of rock affected by compression will likely undergo _______________.
A place that receives less than 50 inches of precipitation per year. ?
A desert is defined as _____________________________.
Strike-slip
A fault that exhibits a large fault scarp is likely a ______________________________ fault.
Anticline
A fold where the limbs dip away from the hinge line is termed a(n) ________________.
Smaller glacially carved valley intersects a larger glacially carved valley
A hanging valley is formed when a _______________.
Aquitard
A layer of rock or sediments with exceptionally low permeability is termed a(n) ___________ in hydrologic contexts.
Formed from sediment that did not travel far from the source before becoming rock
A sedimentary rock made of angular particles most likely ____________________.
Ductile behavior
A warm body of rock is more likely to exhibit ____________ than is a cold body of rock.
14 billion
Among the choices below, the best estimate of the age of the Universe is _____________ years old.
Orogeny
An episode of mountain building is termed a(n) _________________.
Fragmental
An igneous rock made of pyroclastic material has a texture called _______________.
Carbon dioxide
An important long term factor determining whether glacial ice accumulates on the continents has been the concentration of which atmospheric gas?
Firn
An intermediate product in to transformation of snow to glacial ice is ____________.
Spring
Any place where groundwater naturally flows outward at the surface of Earth is termed a(n) _______________.
One-half
As a wave approaches the shore, it will start to "feel bottom" and start to break at a depth equal to ____________ of the wavelength.
Solidify at lower temperatures
As compared to mafic materials, all felsic materials __________________.
An absence of sorting
Sediments deposited directly by glaciers as they melt are characterized by ________________.
There is a large amount of suspended sediment. ?
Some rivers, such as the Rio Grande and Mississippi have a muddy appearance (like chocolate milk). What is the likely cause for this appearance?
By glacial outwash streams
Stratified, sorted sand and gravel are deposited __________.
Firn
Strong winds at the base of glaciers blow fine grain sediments away from the glacier. This material is called __________ when it is deposited.
Strike slip fault
The San Andreas is what type of fault?
Increases
The age of oceanic crust ________________ with increasing distance from a mid ocean ridge.
Multiple properties must be used to identify a mineral.
The single property that can be used to identify any mineral is _______________.
Fault
The surface along which rock on opposite sides is offset by movement is called a(n) _______________.
Colorado, New Mexico, Texas, and Mexico
The watershed of the Rio Grande River covers which of the following areas?
Nonconformity
This surface below sedimentary rocks that overlie igneous or metamorphic rocks is termed a(n) _________.
Isotopes
Two atoms of a single element that differ in number of neutrons are said to represent two distinct __________ of that element.
3.5 or greater
Using the Moh's hardness Scale, a geologist determines that a mineral can be scratched by a copper penny but not a fingernail. What is the approximate hardness of the mineral?
Mountains/other highland areas where streams are beginning their "youthful" stage and flowing rapidly down steep slopes
V-shaped valleys are more likely found in which of the following regions?
He could not conceive of a valid mechanism that would cause continents to shift positions
Wegener's idea of continental drift was rejected by geologists of the day because _______________.
Gravity ?
What agent is responsible for most of the erosion, transportation, and deposition of sediments in deserts?
The crustal root rises out of the mantle.
What happens to the crustal roots of a mountain range as the mountains are slowly eroded away?
Nitrogen
What is the most abundant gas in Earth's current atmosphere?
Stream gradient
What is the term for the slope of a stream bed measured at any point along it's course?
Base level
What is the term used to describe the lowest elevation to which a stream can erode (downcut)?
12.5%
What percentage of parent isotope is expected to remain after the passage of three half lives?
sheild
What type of volcano is the big island of Hawaii?
