Shared Flashcard Set

Details

Rocks, volcanoes, earthquakes
Topics include rocks, volcanoes, earthquakes, and geologic time
88
Geology
Undergraduate 2
04/23/2013

Additional Geology Flashcards

 


 

Cards

Term
What is cleavage?
Definition
The planes of breakage in rocks.
Term
What is a mineral?
Definition
Essentially they are rocks.
Term
What are the characteristics of minerals?
Definition
1. Naturally occurring
2. Solid.
3. Inorganic substance
4. Definite chemical composition
5. Ordered crystal structure
Term
What is Mohs hardness scale?
Definition
It is the scratch resistance of minerals with other minerals. I.E. a fingernail or diamond.
Term
What is silicate?
Definition
One of the two most abundant minerals on earth. Found in the earth's crust. Varied and lots of concentration.
Term
What is carbonate?
Definition
Minerals that have a CO3 -2 compound combined with positive ions. Found abundantly in limestone, and invertebrate shell organisms.
Term
What is silicon-oxygen tetrahedron?
Definition
SoOx4 -4, which is the basic component of the silica tetrahedron. They combine by infusing with oxygen.
Term
What is oxide?
Definition
Minerals have O-2 combined generally with metallic elements, like hematite.
Term
What is a coarse grained texture?
Definition
Large visible crystals, resulting from slow cooling.
Term
Chemical sedimentary rock
Definition
rock materials forms from chemical processes, either biological or non-biological.
Term
Contact Metamorphism
Definition
It is a heat source that comes into contact with the rock.
Term
Detrital sedimentary rock
Definition
the accumulation of weathered rock fragments
Term
Evaporite
Definition
Rock-salt. Dissolved material is left behind when water evaporates.
Term
Extrusive (volcanic)
Definition
Rocks that form at the surface
Term
Fine-grained texture
Definition
fine microscopic crystals that represent fast cooling. Igneous rocks.
Term
Foliated texture
Definition
Banding of mineral concentrations. Orientation of the mineral crystals. Metamorphic rocks.
Term
Glassy texture
Definition
Looks glassy, like obsidian, represents quenching and extremely rapid cooling. Igneous rocks
Term
Igneous rock
Definition
Forms from a cooling liquid
Term
Intrusive (plutonic)
Definition
Rocks that form under the earth's crust
Term
Lava
Definition
what you see as the material oozes out the surface of a volcano or magma plume.
Term
Lithification
Definition
Process of turning loose sediment into detrital sedimentary rock. involves compaction and cementation.
Term
Magma
Definition
Any hot liquid that can be cooled to rock . It is intrusive.
Term
Metamorphic rock
Definition
rocks that form from elevated pressure, heat or chemically active fluids
Term
Nonfoliated texture
Definition
Metamorphic rocks that appear to have no layering. They are granular, sugary and crystalline.
Term
Regional metamorphism
Definition
formed from mountain building and unusually elevated pressure
Term
Rock cycle
Definition
model that describes the formation, breakdown and reformation of a rock.
Term
Sediment
Definition
Naturally occurring material that is broken down by processes of weathering and erosion.
Term
Sedimentary rock
Definition
form from surface activity, typically involving water and the atmosphere.
Term
Weathering
Definition
Mechanical and chemical break down of rocks
Term
Chemical weathering
Definition
process that change the chemistry of mineralogy of a rock. I.e. oxidation
Term
Frost wedging
Definition
when water gets into the cracks of rock, freezes, expands and breaks chunks of rock off
Term
Mechanical weathering
Definition
Breaking of smaller rocks into pieces, increasing surface area.
Term
Parent rock
Definition
Type of rock that existed before it was turned into a metamorphic rock
Term
What is an earthquake?
Definition
ground shaking caused by sudden release of energy usually along a fault
Term
Elastic rebound
Definition
Before an earthquake, plates/rocks slowly bend. After an earthquake, the rocks snap back into shape, and are sometimes deformed as a result of the stress.
Term
Epicenter
Definition
point at Earth's surface where it is directly above the focus of the earthquake
Term
What is the inner core?
Definition
innermost core of the Earth, hottest part
Term
Liquefaction
Definition
strength of soil and rock is reduced during an earthquake due to water seeping into the sediment.
Term
Magnitude
Definition
The measurement unit used for earthquakes.
Term
P-wave
Definition
"Primary" fastest, resemble waves traveling through a spring or slinky
Term
S-waves
Definition
"Secondary" slower, resemble waves traveling through a rope
Term
Richter scale
Definition
Widely used quantitative measure of the magnitude of an earthquake
Term
Surface wave
Definition
travel widely along surfaces of the earth, causes the most damage in an earthquake
Term
Continental Drift
Definition
Theory came with the suggestion of Pangea and about 80 billion years ago, continents started to drift away. Theory never explained how this happened.
Term
Volcanic arc
Definition
When volcanoes grow massive enough to break the surface of the ocean. Multiple islands of volcanoes are called volcanic arches.
Term
Mid-ocean ridge
Definition
underwater mountain range formed by plate tectonics.
Term
Deep sea trenches
Definition
any long, narrow, steep-sided depression in the ocean bottom in which occur the maximum oceanic depths, approximately 7,300 to more than 11,000 metres (24,000 to 36,000 feet). They typically form in locations where one tectonic plate subducts under another
Term
Rift valley
Definition
forms where the Earth's crust is spreading or shifting apart. Makes a narrow valley with steep sides and a flat floor.
Term
Sea floor spreading
Definition
ea-floor spreading is the process in which the ocean floor is extended when two plates move apart. As the plates move apart, the rocks break and form a crack between the plates.
Term
Transform boundary
Definition
faults where the plates slide past one another.
Term
Aa flow
Definition
Lava flow that is blocky, rubble like and jagged in texture.
Term
Cinder cone
Definition
Mostly pyroclastic, smallest and steepest volcano. Ex. Sunset Crater
Term
Composite cone
Definition
Both lava and pyroclastic, an intermediate size and slope. Ex. Mt. Shasta
Term
pahoehoe flow
Definition
Lava flow that has a ropey texture
Term
Pyroclastic
Definition
clastic rocks that are formed from volcanoes. Deadly when spewed at from velocities.
Term
Shield volcano
Definition
Mostly lava eruptions, largest with a gentle slope. Ex Kilauea volcano
Term
What are the 8 most common elements in Earth's crust?
Definition
Silicon, Oxygen, Aluminum, Magnesium, Iron, Calcium, Sodium
Term
What are the three families of minerals?
Definition
Silicates, Carbonates, and Haildes
Term
What is silicate?
Definition
Most abundant family by variety and concentration. Shared with oxygen compounds.
Term
What are carbonates?
Definition
minerals have Co-3 compound that combine with positive ions. Found in limestone and invertebrae organisms.
Term
What are hailides?
Definition
minerals generally have Cl- and F- combined with positive ions. Generally referred to as salts.
Term
What are the types of weathering?
Definition
Mechanical and Chemical
Term
What are some examples of mechanical weathering?
Definition
Frost wedging, pressure release, biological weathering, and abrasion
Term
What are some examples of chemical weathering?
Definition
Acid rain, oxidation, hydration, and dissolution
Term
What are the two main categories of sedimentary rock?
Definition
Detrital - accumulation of weathered fragments
Chemical - rock materials forms from chemical processes, either biological or nonbiological
Term
What are the varieties of detrital sediment and their corresponding sedimentary rocks?
Definition
sedimentary rocks are the most common rocks exposed at Earth's surface. They form as sediment grains (detritus or clasts), weathered and eroded from pre-existing rocks, are deposited as layers in low-lying areas such as valleys, lakes, or an ocean basin.I.E. Shale, Siltstone, Sandstone,
Term
What two processes go into lithification?
Definition
Compaction and Cementation
Term
What does sediment size indicate about the energy of the environment?
Definition
Large sediment size rocks (conglomerates) tend to indicate a high energy environment. Smaller sediments indicates a calmer environment
Term
What are specific examples of high and low energy environments?
Definition
High - Rapids, white water
Low - swamps, deltas, and lake
Term
What are some chemical sedimentary rocks, and how does each generally form?
Definition
Evaporites, Chemical limestone, and tufa. These reactions occur within water that is saturated with positively and negatively charged atoms. Such atoms are naturally attracted to each other, and will form ionic and covalent bonds as they crystallize into solid mineral crystals.
Term
What are some features other than grain size that might be found in sedimentary rocks?
Definition
Ripples, mudcracks, crossbeds, fossils.
Term
what are the two main types of metamorphism?
Definition
Foliated and non-foliated
Term
How do they occur?
Definition
By massive pressure being exerted on the rock.
Term
What texture is associated with foliated and nonfoliated?
Definition
Foliated - layering in metamorphic rocks that is defined by the orientation of the mineral crystals Nonfoliated - grannular, surgary, and crystalline.
Term
What is a parent rock?
Definition
What the metamorphic rock was before it was changed. Examples:
Limestone -> Marble
Quartz Sandstone -> Quartzite
Term
What are examples of contact metamorphism?
Definition
Heat source comes into contact with rock.
Term
Who developed the theory of continental drift?
Definition
Alfred Wegner, German meteorlogist.
Term
What were his observations that supported his theory?
Definition
He observed an ice block breaking apart and came up with the theory along with observing the continents on the map.
Term
What mechanism did he propose to drive continental drift?
Definition
Plate tectonics
Term
Why were his ideas not accepted?
Definition
It didn't explain why/how continents moved, and what was happening on the ocean floor.
Term
After Wegener, where did geologists generally find new information to modify Wegener's theory?
Definition
Harry Hess, used sonar to map out the ocean floor
Term
What are the three basic types of plate boundaries?
Definition
Divergent boundaries, Convergent boundaries, and transform boundaries
Term
What mechanism drives plate tectonics?
Definition
Movement is driven by the convection currents in the mantle and outer core.
Term
What is the difference in amplitude with each increment increase in an earthquakes magnitude?
Definition
It is a 10X increase in magnitude. And a 30X increase in energy.
Term
Catastrophism
Definition
geologic events on Earth occur through sudden cataclysmic processes.
Term
Uniformity
Definition
geologic processes that operated in the past are the very same geologic processes that operate today. "Present is key to the past."
Term
Relative Time Dating
Definition
specific age in years is not given. This type of dating puts events in their correct chronological order based upon the sedimentary layer in which an object is found.
Term
Absolute Time Dating
Definition
The age of a rock in years is called its absolute age. The most common types are based on the rate of decay of naturally occurring radioactive elements. The age of the material being dated is commonly expressed in a number of years. When rocks are formed, small amounts of radioactive elements usually get included. As time passes, the "parent" radioactive elements change at a regular rate into non‑radioactive "daughter" elements. Thus, the older a rock is, the larger the number of daughter elements and the smaller the number of parent elements is found in the rock. Radiometric dating is another term used to talk about Absolute Time dating.
Supporting users have an ad free experience!