Final Exam - Geology Flashcards
What of the following is a mineral?
Ice
What is true of rocks and minerals?
A rock can contain more than one mineral
A mineral is composed of chemical elements
A single rock can include more than one mineral
Which of the following is true about tests we can perform on a mineral?
A softer mineral will scratch a harder mineral
Most common minerals react with dilute hydrochloric acid
A streak plate is used to determine how hard a mineral is
None of these?
What mineral property can be observed without using a test?
Effervescence?
Magmatism?
Hardness?
Cleavage?
What arrangement of atoms is illustrated by 4 atoms in a pyramid form?
Tetrahedron
The mineral halite has cube-shaped crystals because?
Of the arrangement of atoms in crystal lattice
The two most abundant elements in earth’s crust?
Silicon and Oxygen
What causes a water molecule to be polar?
The position of the hydrogen atoms on one side of the molecule
Which of the following igneous rocks would be formed by the slowest cooling?
Coarse granite
Which type of volcano is generally the largest(in terms of covered area)?
Shield Volcano
Hazards associated with basaltic lava flows and eruptions are?
Burial of roads and neighborhoods by lava flows
House fires
Floods from catastrophic melting of ice?
All of these
The most dangerous type of Volcano?
Composite volcano
Some scientists think that Yellowstone could cause a future distaster because
The area is part of a caldera
Scientists think that magma is still present at depth?
Past eruptions from Yellowstone carried ash over a huge area of western North America
Land near Yellowstone is uplifting in some places and subsiding in others
All of these
What is welder tuff?
Igneous rock containing flattened pieces of pumice and small crystals of quartz and feldspar, remnants of a pyroclastic eruption
Which process is not considered to be chemical weathering?
Thermal expansion
Which of the following process is not considered physical weathering?
Oxidation
When do angular clasts form?
Steep slopes in a mountain
Which characteristic is not used to classify and name clastic sediments?
The climate in which the clasts are produced
If a rock is poorly sorted, the rock contains what?
A wide range in the size of clasts
How does the sedimentary layer known as a cross bed form?
Piling of sediment down the front of a dune or ripple of water
If a rock is subjected to differential stress, this means that?
The amount of stress is greater in some directions than in others
Which of the following is most likely to occur at shallow crust levels?
Brittle deformation
What is a principle we use to determine the age of a landscape surface?
A surface with a well-developed soil is probably older than a surface with no soil.
The term half-life represents the time it takes?
For half of the parent atoms to decay into daughter atoms
Igneous rock?
Igneous rock is formed through the cooling and solidification of magma or lava.
Sedimentary rock?
Sedimentation is the collective name for processes that cause mineral and/or organic particles (detritus) to settle and accumulate or minerals to precipitate from a solution.
Metamorphic Rock?
arise from the transformation of existing rock types, in a process called metamorphism, which means “change in form”
Most oceanic plateaus are?
Constructed by volcanic eruptions probably over mantle plumes
Most oceanic islands and seamounts are?
Constructed by volcanic eruptions that first occur underwater
Island arcs are curved because?
Earth is a sphere, not a flat plane
How do most salt deposits form?
Evaporation of water, such as in restricted seaways
Regional elevations on land are primarily controlled by?
The thickness of the continental crust
Which of the following is NOT a setting in which regional mountain belts form?
Passive Margin
What could cause a region to be higher in elevation than an average part of a continent?
Less dense continental crust
Main cause of death associated with 2004 indonesian earthquake?
Large ocean wave or Tsunami
When do rocks along a fault have the highest amount of stress and stored elastic strain?
Right before an earthquake
How do we determine the location of a recent earthquake?
Use seismic records from three or more stations
Sudden movement on a fault can cause a tsunami when?
The fault suddenly uplifts or downdrops the seafloor
Which is the least at risk for a geologic hazard?
On soils that gently expand when wet
What does NOT physically loosen rocks on the surface?
Water contracting as it freezes
What happens to the surface area of exposed rock if a rock is fractured?
The surface area increases as the rock is fractured
What is the main reason why oceans are salty?
Weather of rocks releases chemical elements that make the oceans salty
Some rocks and minerals are not stable at the surface because they?
Are exposed to water? Formed in high-temperature environments? Formed in high-pressure environments Are exposed to oxygen? All of these*
What happens when rocks oxidize near Earth’s surface?
Minerals, especially those with iron, combine with oxygen
What is the main force involved in the stability of slopes?
Gravity
What is the angle of repose?
The steepest angle at which loose material remains stable
What happens to snowflakes as they become progressively bured within glaciers?
They become interlocking crystals of ice
What carves U-shaped valleys?
Glaciers
What happens when a glacier encounters the sea or lake?
Large blocks of ice collapse off the front of the glacier and become icebergs
The margins of glaciers are usually darker than the interior primarily because?
The sides have a higher concentration of rocks and other debris
What is permafrost?
The portion of the ground that remains frozen throughout the year
How are silt deposits called loess related to glaciers?
They are wind-blown accumulations and commonly are derived from glaciers
A delta forms when?
A river slows and deposits sediment as it enters a lake or sea
The size of clasts that a stream can carry is primarily controlled by?
The velocity and turbulence of the current
Which particles of sediment are most likely to be transported as suspended load?
Small, low density particles
