Geology Final

Front 1

Geological Principles: Uniformitarianism

Back 1

Processes operating at the present are the same processes that have operated in the past.

Front 2

Geological Principles: Original Horizontality

Back 2

Beds of sediment deposited in water were formed as horizontal of nearly horizontal layers. Normal for most sedimentary rocks.

Front 3

Geological Principles: Superposition

Back 3

The layers of undistributed sedimentary rocks get younger going from bottom up. Oldest--> youngest.

Front 4

Geological Principles: Principle of Lateral Continuity

Back 4

Usually sediments will accumulate as continuous sheets in an area. Subsequent erosion can remove materials making them discontinuous.

Front 5

Geological Principles: Cross-Cutting Relationship

Back 5

The disruption (folding/tilting) is younger that the original layering of the rocks.

Front 6

Geological Principles: Principle of Fossil Succession

Back 6

Fossils are the preserved remains or traces of organisms from the past.

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Geological Principles: Inconclusions

Back 7

Fragments of rock unit that are found within another rock unit.

Front 8

Stratigraphic Column

Back 8

A vertical cross-section where the rock layers are divided into stratigraphic fragments.

Front 9

Unconformities

Back 9

Rock layers that are deposited over time mainly without interruptions are said to be conformable beds. (GAP IN TIME)

Front 10

Unconformities- Three Types

1. Angular

Back 10

Where the tilted beds underlies a horizontal bed.

Front 11

Unconformities- Three Types

2. Non-conformity

Back 11

Where a break in time occurs between older metamorphic or igneous rocks and younger sedimentary rocks.

Front 12

Unconformities- Three Types

3. Disconformity

Back 12

Where a gap in time is not readily apparent with horizontal beds on either side.

Front 13

Metamorphic Rock

Back 13

Are formed by the transformation of pre-existing rock by high pressure, temperature, or chemically active fluids.

Front 14

Foliated Rocks

Back 14

Occur when there is pressure and the composition of the rock includes minerals such as mica. Platy mineral, layered look.

Front 15

Non-Foliated Rocks

Back 15

Occur when the pressure is low or not a factor or the composition of the rocks does not include platy minerals such a mica. Marble.

Front 16

Deformation

Back 16

The changes in size or form of a rock that occurs when subjected to forces greater than its strength.

Front 17

Force

Back 17

A force is any influence that causes a free body to undergo an acceleration.

Front 18

Pressure

Back 18

A type of stress.

Front 19

Differential Stress

Back 19

Describes when stress is unequally applied.

Front 20

Compositional Stress

Back 20

Occurs with collisions when plate margins come together, causes folding and some faulting.

Front 21

Tensional Stress

Back 21

When plate margins or rocks are pulled apart. Results in faulting.

Front 22

Shear Stress

Back 22

Slippage, rock surfaces of plates sliding past each other. Stress that acts parallel to a surface.

Front 23

Deformation is Depedent on?

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Speed- Slow speed, the rock deforms elastically and can snap back to original shape.

Rock Type- Some are brittle, some can bend.

Location- Often fractures occur in rocks near the surface with low confining pressure and temp.

Front 24

Strike and Dip Box

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Water flows down an inclined surface parallel to the dip. The strike is always 90' to the dip.

Front 25

Dip

Back 25

Angle of the inclined surface from horizontal (45')

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Strike

Back 26

The compass bearing of a horizontal surface when intersects an inclined surface.

Front 27

Anticlines

Back 27

The upfolded parts of the rock layers (arch).

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Syncline

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The down folded parts of the rock layer (trough).

Front 29

Faults

Back 29

Fractures along which there has been some movement.

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Hanging Wall

Back 30

The wall directly above the fault line.

Front 31

Foot Wall

Back 31

The wall directly below the fault line.

Front 32

Fault Surface (PLANE)

Back 32

The fracture surface between one block and another along which movement occurs.

Front 33

Focus

Back 33

Origin of the earthquake, the point within the crust where movement first occurred.

Front 34

Body Waves

Back 34

Travel through the earths interior. P-waves (primary) push waves, and S-waves (secondary) up and down.

Front 35

Surface Waves

Back 35

Travel through the lithosphere. Love waves and Rayleigh waves. Form from unexpended P and S waves

Front 36

P-Waves

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Push waves, compression waves, the first to be detected at a recording station. Velocity 4-10km/sec. Transmit through solid of fluid material.

Front 37

S-Waves

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Shear waves, a shearing motion only goes through rock material. Velocity 2-5km/sec.

Front 38

Mercalli Intensity Scale

Back 38

Perceptions by people near the epicenter, therefore is subjective. has 12 degrees of intensity.

Front 39

Richter Scale

Back 39

Based on the maximum amplitude of seismic waves (P/S) and to distance.

Front 40

Movement Magnitude (Mw)

Back 40

Expresses the total energy released over the entire fault zone and the volume of rock involved.

Front 41

Six Volcanos/Eruption Types

1. Flood Basalts

Back 41

Made of basaltic lava. Very fluid, ejected from a fissure, and the low viscosity lava floods over the land.

Front 42

Six Volcanos/Eruption Types

2. Shield Volcanos

Back 42

Largest Volcanos. Form from basalt, gentle slopes (5'-12'). Eruptions via fissures and vents.

Front 43

Six Volcanos/Eruption Types

3. Cinder Cones

Back 43

A small volcano cone. The slope angle is approx. 24'-32' to the horizontal.

Front 44

Six Volcanos/Eruption Types

4. Composite Cones or Stratovolcanos

Back 44

Intermediate in size, variable slope angles.

Front 45

Six Volcanos/Eruption Types

5. Caldera

Back 45

A volcanic crater that develops from the explosion and collapse of a composite volcano.

Front 46

Six Volcanos/Eruption Types

6. Other

Back 46

Lava Domes- Lava flows quickly and piles up at vent.

Splatter Cones- Very small.

Volcanic Plugs- Lava cools and plugs the vent.

Front 47

Weathering Processes

1. Frost Wedging

Back 47

Block fields surface with angular blocks likely due to weathering.

Front 48

Weathering Processes

2. Thermal Expansion

Back 48

Heating and cooling results in differential expansion and contraction. Stresses the rock and eventually breaks the bonds within the rocks.

Front 49

Weathering Processes

3. Salt Crystal Growth

Back 49

Occurs in arid regions, and marine coastlines.

Front 50

Weathering Processes

4. Plant Wedging

Back 50

Seed exploits crack in rock as root grows it exerts force on surrounding rock.

Front 51

Six Main Weathering Processes

1. Dissolution

Back 51

Dissolving of solid rock material in water. Not a permanent process.

Front 52

Six Main Weathering Processes

2. Carbonation

Back 52

Water and Co2 combine to form a weak acid that is effective on certain rock groups.

Front 53

Six Main Weathering Processes

3. Hydration

Back 53

The absorption of water molecules in the mineral molecules. Results in swelling of rock and disruption of structure.

Front 54

Six Main Weathering Processes

4. Hydrolysis

Back 54

The absorption of water by a rock to form a new material.

Front 55

Six Main Weathering Processes

5. Oxidation

Back 55

Formation of rust.

Front 56

Six Main Weathering Processes

6. Chelation

Back 56

Rocks decomposed by the action of organic acids produced by organisms.

Front 57

Soil

Back 57

Soil = f (CLORPT) + HI Climate, organisms, relief, parent material, time, and human impact.

Front 58

Zone of Leaching

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Removal and transportation of soil mineral in suspension and/or in solution within the soil by downward or lateral movement of water.

Front 59

Zone of Accumulation

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Where ion and clays accumulate.

Front 60

Illuvation

Back 60

Depositional processes of soil material that has been transported from one horizon to another.

Front 61

Mass Wasting

Back 61

Based on rate of movement, type of material, and type of movement.

Front 62

Mass Wasting Movement

1. Creep

Back 62

Slowest type of movement by gravity of any type of material. Very widespread, imperceptible.

Front 63

Mass Wasting Movement

2. Flow

Back 63

Materials on a slope becomes saturated with water, from heavy rain/snow melt and material is liquified leading to fluid deformation.

Front 64

Mass Wasting Movement

3. Slide (slip/slump)

Back 64

Occurs on a very steep slope where materials slide along a well defined shear zone.

Front 65

Mass Wasting Movement

4. Fall

Back 65

Free fall of materials detached from steep surfaces (cliffs), little contact with face once launched, so reaches high speeds.

Front 66

Geological Time Scale

Back 66

Geological events are placed into a chronological (absolute time) and hierarchical framework (relative time).

Front 67

Geological Time Periods

Pretty Cold Oysters Seldom Develop Coloured Pearls, Their Juices Congeal Too Quickly

Back 67

Pre-cambiran, cambrian, ordovician, silurian, devonian (develop), carboniferous, permian, triassic, jurassic, cretaceous, tertiary (mammals), quaternary.

Front 68

Absolute Age

Back 68

Actual age/ time in years (carbon dating).

Front 69

Relative Age Dating

Back 69

The relative order of events within a sequence.