Unit 2 Natural Hazards And Geophysical Disasters Flashcards
What is a natural hazard?
A naturally occurring phenomenon caused by a slow or rapid onset of the physical process of planet Earth
What are the five classifications?
Geophysical- earthquake tsunamim
Meteorological -hurricanes tornadoes
Hydrological flooding avalanches
Climatic drought, wildfires
Biological infectious disease diseases
What is the difference between a natural hazard and a natural disaster?
A natural hazard becomes a natural disaster when it has a negative effect on humans. All natural disasters are natural hazards, but not the other way around.
What are human disasters?
Are human disasters, dangerous event triggered by human actions and decisions examples are oil spills nuclear, meltdowns, wars, and dam bursts.
What is a natural to human disaster?
Tsunami causing a nuclear meltdown
What is a natural natural disaster
Hurricane to flooding
What is a human to natural disaster?
Deforestation to landslides
What is plate tectonics
The theory that the earth surface is divided into slabs the interact with one another in constant motion. These are floating on a molten layer of rock called magma.
What is the continental drift?
The theory of how gradual movements of continents have created the current position of earths land masses evidence of this consists of the same fossils being on two different continents
What is a convergent boundary?
When two plates come together, usually on a coastline creates mountain ranges also known as a subduction zone
What is a divergent boundary?
Two tectonic plates move away from each other, and it usually occurs under the ocean happens in northern Africa and Iceland and formed mid ocean ridges
What is a transform boundary?
Slide past each other natural and human made objects on these get split apart cause of earthquakes
Why do volcanos erupt
Pressure from the heat of the magma deep within the earth forces, molten rock through cracks and weak spots
Where are volcanos commonly located?
Volcanos are commonly located over convergent boundaries or places in the earths crust that are thin
What are three types of volcanos
Composite shield and Cindercone
What is a volcanic hotspot?
Volcanic regions occurring away from plate boundaries that are fed by magma plumes near the surface of the earth
What is a tsunami
A series of waves caused by the displacement of a large volume of water
How was the tsunami caused?
After a large displacement of water energy is released displacing the water, raising it above the normal sea level gravity, pulls it back down, making it ripple outward with less water to move through the wave slows down, and the energy moves upwards the water retreats
