NATURAL HAZARD Flashcards
a natural process and event that is a potential threat to human life and property
natural hazard
3 types of natural hazard
Geologic Hazards
Hydrometeorological Hazards
Coastal Hazards
a hazardous event that occurs over a limited time span in a defined area.
disaster
a massive disaster that requires significant expenditure of money and a long time (often years) of recovery to take place
catastrophe
- used to describe the complex interactions between the component sub-cycles of tectonic, rock, hydrologic and biogeochemical cycles
Geologic cycle
– involves the creation, movement, and destruction of tectonic plates
Tectonic cycle
– the largest of the geologic sub-cycles, and is linked to other sub-cycles.
Rocks cycle
is a natural geologic event that can endanger human lives and threaten human property.
geological hazard
is the trembling of the Earth’s surface that occurs when the energy in the form of strain in rock layers is released.
earthquake
Basic Earthquake Features:
- epicenter
- hypocenter
– place on the surface of the earth above where the ruptured rocks broke up to produce an earthquake
Epicenter
– directly below the focus. The point of initial breaking or rupturing within the earth
Hypocenter (focus)
Earthquakes are measured and compared by:
- intensity
- magnitude
- moment magnitude
- ritcher scale
- effects of ground motion on people and structure
Intensity
- amount of energy an earthquake released
Magnitude
– indicates the size of the earthquake with a decimal number.
Moment magnitude
– developed by famous seismologist Charles Ritcher
-Still used by some news reporters
Ritcher Scale
is a number which is measure if energy released in an earthquake
magnitude
is a measure of the strength of shaking during the earthquake
intensity
Effects of earthquakes and linkages with other natural hazards
- Shaking and ground rupture
- liquefaction
- Regional changes in land elevation
- landslides
- fire
- disease
is a downslope movement of a mass of rock, debris, earth, or soil (soil being a mixture of earth and debris). A slope is a slant or incline on a land surface.
landslide
– mineral composition, degree of cementation or consolidation, the presence of zones of weaknesses
Earth material
– Topographic relief refers to the height of the hill or the mountain above the land below.
Topography and slope angle
– weather that is typical in a place over a period of years or decades.
Climate
– all the plants or plant life in a place.
Vegetation
is caused by spreading and sinking of lithospheric plates at plate boundaries that interact with other earth materials that produce magma.
Volcanic activity