Natural Hazards Definitions (E) Flashcards
1
Q
A’a lava
A
Flows with a rough surface
2
Q
Abyssal plain
A
Flat region of the ocean floor
3
Q
Acid rain
A
Carbon mixing with the rain - chemical weathering
4
Q
Aseismic building design
A
Buildings designed to withstand + minimise destruction during an earthquake
5
Q
Ash
A
Light material from a volcano
6
Q
Asthenosphere
A
Portion of the earths mantle, it’s the denser, weaker layer beneath the lithospheric mantle
7
Q
Basal drag
A
Convection currents creating friction on underside of plate dragging it ,18cm a year
8
Q
Batholith
A
Large body of igneous rock formed beneath earths surface
9
Q
Caldera
A
Large depression formed when a volcano erupts + collapses
10
Q
Collision Zone
A
Formed when two continental plates collide
11
Q
Composite cone
A
Large volcanoes, active over long periods + erupt periodically
12
Q
Constructive margin
A
Plates move appart
13
Q
Continental crust
A
The crust beneath land
14
Q
Continental drift
A
The movement of continents (from tectonic plates)
15
Q
Convection current
A
The movement of the mantle
16
Q
Coriolis
A
Circulatory air deflected to north + south hemisphere
17
Q
Craton
A
Rock with diamonds
18
Q
Cyclone
A
rotating counterclockwise winds, low centre pressure
19
Q
Destructive margin
A
Plates move together , subduction or collisional
20
Q
Epicentre
A
The first area of land felt by the earthquake
21
Q
FAF
A
Fatalism
Adaptation
Fear
22
Q
Fire - creeping
A
A fire spreading slowly with a low flame
23
Q
Fire - running
A
A fire without control
24
Q
Flammable
A
Easily set on fire
25
Focus
The point where a hazard directly occurred
26
Fold mountains
Where earths continental plates are pushed together
27
Geophones
A detector that responds to ground vibrations generated by seismic waves
28
Hazard
Something that may cause loss of life + property damage
29
Hazard perception
People seeking hazards as a natural event, not controlled by humans
30
Hazard zone mapping
Provided information for the public about areas which are under great threat and which are safer
31
Horst and Graben landscape
Where earths crust is pulled apart areas of land fall down
32
Hotspot
A large plume of hot mantle material
33
Hurricane
Giant tropical storms, warm water is sucked in
34
Island arc
A line of islands that forms from volcanic activity along a subduction zone ,causing fractures in the plate parallel to the boundary lets magma rise
35
L wave
Earthquakes wave that travels around the earths surface and is usually the 3rd conspicuous wave to reach a seismograph
36
Lahar
Hot and cold mix of water and rock that flows down volcano slopes
37
Lava
Molten rock from a volcano on land
38
Lava - andesitic (high or low viscosity)
High viscosity
39
Lava - basaltic (low or high in silica)
Low in silica, runny
40
Lava - rhyolitic (viscous yes or no)
Viscous , thick blocky lava flows
41
Liquefaction
Water saturated sediment temporarily loses strength and acts like a liquid due to high shaking
42
Lithosphere
Solid , outer part of the earth - crust
43
Magma
Molten rock underneath land
44
Magma plume
Areas of hot upwelling mantle
45
Mass damper
Device in structures to stop buildings collapsing
46
Mercalli scale
Measures earthquake intensity on a scale of I to XII
47
Mitigation
To reduce the seriousness of a situation
48
Mountain root
A rock layer beneath the ground extending as far as 10 to 15x the mountains height
49
Multi-hazard environment
More than one hazard e.g. volcano, earthquakes, tropical storms
50
Risk sharing
When everyone in a road buys insurance, it lowers the individual price of insurance for each house.
51
A nuée ardente
Fast moving cloud of hot gas + ash from a volcano
52
Ocean ridge
Where oceanic crusts move appart (constructive)
53
Ocean trench
Where two oceanic destructive plates meet , and one is sub-ducted creating a trench
54
Oceanic crust
The crust under water
55
P wave
The first waves to arrive at a seismograph, solid liquid and gas
56
Pahoehoe
Has a smooth surface whilst the lava is moving
57
Palaeomagnetism
At constructive margins rock sections are being newly formed (newest in the middle) all the rocks contain different magnetic fields
58
Park model
Plots the quality of life after a disaster occurs (against time)
59
Passive margin
Transition between oceanic + continental plate
60
Phreatic explosion
Steam- driven explosions underneath ground by volcanic activity
61
Plate margin
Where the edge of a tectonic plate is
62
Pluton
Body of igneous rock, from magma steadily cooling
63
Pyroclastic flow
800 degrees C <
Mix of rock fragments , gas + ash that travels rapidly
64
Return interval
Average time between events
65
Richter scale
Measures earthquakes, exponential scale
66
Ridge push
A pushing force that plates experience when they have magma pushing up
67
Rift Valley
Flat + low-lying valley that forms at geographical crack/ separation
68
Risk
Exposure of people to a hazardous event
69
S wave
Lateral waves, side to side (perpendicular) second seismic wave to reach .
70
Saffir- Simpson scale
5 point scale of hurricane intensity. Starts at 74mph, 5 scales (5 is the worst)
71
Seismic gap theory
Based on the assumption that all parts of a fault move eventually. If an area has been fine for a while soon there will be one
72
Shield volcano
Low viscosity lava, spreads from source on gentle slopes
73
Silica
SILICA IS STICKY
High silica = thick + sticky
Low silica = runny + smooth
74
Slab pull
Pulling force exerted by a plate being sub-ducted
75
Stockpiling
Storage location for bulk materials
76
Storm surge
Raise in sea level due to force by a storm
77
Subduction
Where a plate is forced bellow another
78
Surface deformation
Change in earths surface by tectonic forces
79
Tephra
Anything thrown into the air during a volcanic eruption
80
The 3 P’s
Predict
Prepare
Prevent
81
The Sendai framework
Addresses the dimensions of disaster risk In order to prevent new risk + reduce existing risk
82
Transform fault
2 plates slide past one another
83
Tropical storm
Very powerful low-pressure weather system
84
Tsunami
Large wave caused by earthquake bellow water
85
Tuned Mass Damper
Moves in opposing direction to seismic hazard waves
86
Typhoon
An intense circular storm, originates over warm oceans
87
VEI
Volcanic expolsivity index
Based on magnitude + intensity
88
Viscosity
Fluids resistance to flowing
89
Volcanic bomb
Lump of lava thrown out by an erupting volcano
90
Vulnerability
Potential for loss
91
Wind shear
A difference in wind speed + direction over a relatively short distance in the atmosphere
92
Perception
The way people view the threat which determine their response
93
Antecedent conditions
Conditions before the event
94
Conservative margins
Plates moving past each other
95
Magnitude
How strong the earthquake is
96
Ladder fuels
The vegetation that allows fire to spread like fuel
97
Entrapment
Where someone is stuck in fire
