Shared Flashcard Set

Details

Geology of National Parks
Test 1
68
Geology
Undergraduate 2
10/09/2010

Additional Geology Flashcards

 


 

Cards

Term
Number of National Parks
Definition
58 National Parks
Term
Number of National Monument
Definition
74 National Monuments
Term
Difference Between a National Park and a National Monument
Definition

National Monument: created by Presidential Decree (Antiquities Act of 1906)

 

National Park: established by an Act of Congress (Organic Act of 1916)

Term
National Preserve
Definition
almost identical to National parks, all the attributes of NP but with hunting seasons
Term
Goals of the National Park Service
Definition
  • To preserve natural areas for future generations
  • To provide for enjoyment of natural areas by the public
Term
First National Park
Definition
Yellowstone National Park - March 1, 1872
Term
Topography
Definition
is the study of Earth's surface. It specifically involves the recording of relief or terrain (the three dimensional quality of the surface) and the identification and characterization of specific landforms
Term
Relief
Definition
corresponds to the variable elevations (or inequalities) in the land surface
Term
Continental Divides
Definition
is a line drawn on a map that forms a boundary between two large land areas such that precipitation falling on one side of the line eventually drains to one body of water (ocean) and precipitation on the other side drains to another body of water, generally on the opposite side of the continene
Term
Drainage Basin
Definition
is an extent of land in which rain or snow melt drains downhill into a body of water- such as a river, lake, estuary, wetland, sea, or ocean
Term
Drainage Divides
Definition
are lines drawn on a map that separate adjacent drainages
Term
Physiographic province
Definition
is a geographic region in which the geology and climate have given rise to an array of landforms that are similar in character and origin, and which differ significantly from the landform patterns in adjacent regions
Term
V shaped valley
Definition
carved by water like the Great Smoky Mountains
Term
U shaped Valley
Definition
carved by glacier like in Glacier National Park
Term
Catastrophism
Definition
Earth has been affected y numerous, sudden, short-lived, and violent events- global in scope... George Cuvier
Term
Uniformitarianism
Definition
Natural processes operating in the past are the same as those observed in the present (rates may be different)- present is the key to the past... James Hutton
Term
Chicxulub Impact
Definition
represent the fact that catastrophes do occur on Earth- led to tsunami, fire, seismic shaking
Term
Catastrophic Events
Definition
Earthquakes, tsunamis, volcanic eruptions, floods, etc.
Term
Gradual Processes
Definition
erosion, deposition, uplift, flow of rivers, movement of glaciers, wave motion, etc
Term
Principles and assumptions of relative time
Definition
  • Original horizontality:once flat, then bent
  • superposition: relative sequence if on bottom came first
  • cross-cutting relationships: tears were once whole
  • occurrence of inclusions: one rock included in another, whatever is included is older
Term
How are time periods named?
Definition
based on fossils found
Term
Absolute Time
Definition
a measurement, in some units of time
Term
Relative Time
Definition
sequence of events
Term
Use of Correlation in Relative Time
Definition
  • similarity of rock type
  • similarity of rock sequence
  • use of fossil, mineral, or chemical evidence
Term
Geologic time scale
Definition
  • Eon
  • Era
  • Period
  • Epoch
Term
Units of Geologic Time
Definition
  • year= annum (a)
  • thousands= Ka
  • millions of years = Ma
  • billions of years= Ga
Term
Eon
Definition
  • Phanerozioc (542 Ma-present) visible life
  • Proterozoic (2500-542 Ma) primitive life
  • Archaean (2500-3850 Ma) hidden life
  • Hadean (~4550-3850 Ma) hellish conditions
Term
Era
Definition
  • Precambrian (4550-542 Ma) no macroscopic life forms
  • Paleozoic (542-245 Ma) Age of Amphibians
  • Mesozoic (245-66 Ma) Age of dinosaurs
  • Cenozoic (66 Ma- present) Age of Mammals
Term
Unconformities
Definition
  • gaps in the rock record
  • a long period of time during which deposition ceased, ersosion removed previously formed rocks, and then deposition resumed
  1. Disconformity:
  2. Angular Unconformity
  3. Nonconformity
Term
Disconformity
Definition
  • sedimentary rock overlying sedimentary rock
  • period of non-deposition and/ or erosion
  • more common but far less conspicuous
Term
Angular Unconformity
Definition
  • sedimentary rock overlying sedimentary rock having a different orientation
  • period of "mountain- building"/ uplift and erosion
  • consists of tilted or folded sedimentary rocks that are overlain by younger, more flat-lying strata
  • indicates that during pause in deposition, a period of deformation (tilting or folding) and erosion occured
Term
Nonconformity
Definition
  • sedimentary rock overlying metamorphic or igneous rock
  • period of extensive erosion followed by subsidence and deposition
  • there must have been period of uplift and the erosion of overlying rocks
Term
Metamorphic Rock
Definition
rock formed by the alteration of pre-existing rock deep withinn Earth (but still in solid state) by heat, pressure, and or chemically active fluids
Term
Igneous Rock
Definition
A rock formed by the crytallization of molten magma
Term
Sedimentary Rocks
Definition
Rocks formed from the weathered products of preexisting rocks that have veen transported, deposited, and lithified
Term
Sediment
Definition
Unconsolidated particles created by the weathering and erosion of rock, by chemical precipitations from solution in water, or from the secretions of organisms, and transported by water, glaciers, or wind
Term
Stress
Definition
  • equal the force per unit area (pressure) exerted against an object
  • ex. two hands pushing against one another
Term
Uniform Stress
Definition
  • stress in all directions
  • ex. when under water, water pressure from all sides
Term
Directed Stress
Definition
  • stress in one direction
  • ex. one hand forcing the other in one direction
  • directed stress can result in compression, extension, or shear
Term
Strain
Definition
  • the deformation (permanent or temporary) produced in any material as a result of applied stress
  • stress produces strain

 

Term
Confining pressure
Definition
  • equal from all sides
  • reduces volume
Term
Compression
Definition
shortens distance between two points
Term
Extension
Definition
lengthens distance between two points
Term
Shear
Definition
acts in parallel but opposite directions
Term
Deformation
Definition
  • all changes in the original shape and / or size of a rock body
  • rock deformation controlled by material properties, time, temperature, and pressure
Term
Elastic
Definition

material rebounds to original form when stress is removed (however there is a limit)

 

Ex. bendable wood

Term
Brittle Failure (fracture)
Definition

results when the elastic limit is exceeded- permanent failure

 

ex. snapping wood in two

Term
Plastic
Definition

material remains deformed when stress is removed

 

ex. sqeezing clay

Term
Strike
Definition
orientation of a horizontal line within the plane of a tilted rock layer
Term
Dip
Definition
angle from the horizontal of that inclined layer (measure perpendicular to the strike)
Term
Fault plane
Definition
displacement of rocks along a large planar fracture
Term
Normal faults
Definition
  • result of extension
  • hanging wall (down)
  • foot wall (up)
  • dip (inclination) generally from 45- 90 degree
Term
Reverse faults
Definition
  • result of compressions
  • hanging wall (up)
  • foot wall (down)
  • dip greater than 45 degrees
Term
(low angle reverse faults) Thrust faults
Definition
  • result of compression
  • thrust faults can place older rocks over younger rocks and can have displacements measured in many tens of km
  • thrust faults provided the key to understanding the geology of Glacier NP and the Great smoky Mtns. NP
  • shorten things by stacking things up
Term
Transcurrent or strike-slip faults
Definition

 

  • result of shear
  • dominant displacement is horizontal and parallel to the trend, or strike, of the fault surface 
  • typically steep or near vertical

 

Term
Hanging Wall
Definition
where is miner's head is
Term
Foot Wall
Definition
where the miner's feet are
Term
Folds
Definition

 

  • Limb: area of least curvature
  • Hinge: area of maximum curvature
  • Hinge Line: (fold axis)
  • Hinge plane (axial plane)

 

Term
Types of Folds
Definition

 

  • Anticline (antiform) - closes upwards
  • Syncline (synform)- closes downwards

 

Term
Shapes of Folds
Definition

 

  • Normal or symmetric- limbs have same inclination on both sides
  • Asymmetric
  • Overturned
  • Plunging: v shaped outcrop pattern- arrowhead

 

Term
ages of rock exposed in folds
Definition

 

  • Anticline: oldest rocks in core of fold- layers pushed up then eroded
  • Syncline: youngest rocks in core of fold

 

 

Term
Earthquake
Definition
  • the vibration of eath produced by the rapid release of energy- caused by slippage along a fault in the earth's crust
  • energy released radiates in all directrions from source, focus in the form of waves

movement (displacement) along a fault zone...

  • releases seismic energy
  • transmitted through Earth and along the surface
  • manifested as an earthquake

earth's crust is under stress, stress builds to the point that the earth breaks, EARTHQUAKE

 

Term
P-Waves
Definition
  • body wave
  • primary
  • compressional
  • particle motion parallel to direction of propagation
  • same direction energy is moving
  • alternately expand and contract
  • body waves go through earth
  • travel the fastest
  • transmitted by both solids and fluids because the resist a change in volume when compressed and will elastically spring back once the force is removed
  • push pull waves- they push (compress) and pull (expand)
Term
S-Waves
Definition
  • body wave
  • secondary
  • shear
  • particle motion is perpendicular to direction of propagation
  • particle motion is perpendicular to seismic energy
  • energy goes left to righ, motion goes up and down
  • transmitted only by solids
  • tells us part of earth's core must be fluid at some point b/c it doesn't transmit s waves
  • temporarilu change the SHAPE of the material so fluids don't respond
Term

Seismic Surface Waves

 

Definition
  • energy dissipates with depth
  • maximum intensity at surface
  • love waves: back and forth motion
  • Rayleigh Waves: retrograde rolling motion
Term
Structure of earth's Interior
Definition
  • crust (silicate)
  • mantle (silicate)
  • core (ni-Fe  metal)
  • Earth's outer core is fluid, responsible for magnetic flied and, in part, drives mantle convection
Term
Fault
Definition
large fractures in Earth's crust
Supporting users have an ad free experience!