D - Spatial Distribution of Geophysical Hazard Events Flashcards
What are three main tectonic hazards?
Earthquakes, volcanoes, and tsunamis.
Where do most of the world’s earthquakes occur?
Near plate boundaries, such as along the Mid-Atlantic Ridge or around the Pacific Ocean.
How do subduction zones and collision boundaries affect earthquake distribution?
They tend to produce broad belts of earthquakes due to the complex stresses and faulting in these zones.
What type of plate boundary is typically associated with narrower earthquake belts?
Constructive (divergent) and conservative (transform) boundaries.
Name one human activity that can induce earthquakes away from plate boundaries.
Construction of large dams, mining, or nuclear weapons testing.
Where are most active volcanoes located?
At or near plate boundaries, especially along the Pacific Ring of Fire.
What is a hotspot volcano?
A volcano that forms over a plume of hot material rising from deep in the mantle (e.g., Hawaiian Islands).
Which volcanic region contains about three-quarters of Earth’s historically active volcanoes?
The Pacific Ring of Fire.
Give an example of a hotspot volcano chain.
The Hawaiian Islands, located in the middle of the Pacific Plate.
What factors make fatal landslides more likely in certain areas?
Active tectonics (uplift, earthquakes), high rainfall, and high population density.
Why are landslides often more deadly in low-income countries?
They lack defensive structures (e.g., retaining walls) and have limited resources for prevention.
Name one region where fatal landslides are common.
The southern edge of the Himalayas, central China, southwest India, or central Indonesia.
How do tectonic processes influence landslide frequency?
Uplift and seismic activity can destabilize slopes, making landslides more likely.
Why is the western edge of South America prone to landslides?
It has active tectonics, high rainfall in some areas, and steep mountain slopes along the Andes.
