Plate Boundaries
What large-scale Earth feature do linear belts of earthquakes volcanoes help identify?
Plate boundaries (or tectonic plate edges)
What is a hotspot and where (relative to plates) are hotspot volcanoes often found?
A hotspot is a stationary upwelling of magma in the mantle; hotspot volcanoes can form in the middle of plates
What does a seismograph directly record?
Ground motion overtime caused caused by seismic waves
What is the main piece of evidence scientists use when identifying high-risk earthquake areas?
Locations of past earthquakes
Given the USGS map: Which town did Mr. Jost grow up in?
Sandy
Name the three main types of plate boundaries and give one motion type for each.
Divergent (plates move apart), Convergent/subduction (plates collide/one sinks), Transform (plates slide past each other)
Based on the Hawaiian islands ages, which island is more likely to have an active volcano now and why?
The Island of Hawaii is the youngest, the hotspot is currently beneath the youngest island, so its most likely active.
How do scientists use long-term seismograph records to inform hazard assessments?
To identify where earthquakes are more likely to occur and to refine hazard maps
Using the USGS map: Which locations would be erased from the map if Mt. Hood erupted?
Timberline Lodge and Government Camp
What is the only land mammal that can't jump?
The Elephant
Explain why most volcanic and earthquake activity occurs along plate boundaries.
Plate interactions create stress, melting, and seafloor spreading.
Which island is the oldest island in the Hawaiian island chain and why?
The island of Kauai is the oldest because it is the farthest away from the hotspot.
What conclusion about global earthquake distribution was supported when scientists compared seismograph records from many locations?
That earthquakes cluster in narrow zones aligned with plate boundaries, supporting plates tectonics
Given the USGS map: You are a contractor and your client has asked you to determine a building location west of Mt. Hood. Which location would you recommend and why?
Estacada, because it is the farthest west and outside of the lava flows (green area)
What engine comes stock in a 1965 Ford F100 Custom Cab?
V8 352 cubic inch
The San Andreas Fault is an example of which type of plate boundary? Describe the relative motion of the plates there.
Transform boundary- plates slide horizontally past each other.
In what state and year did Mt. St. Helens erupt?
Washington, 1980
After a major earthquake a region experiences many smaller aftershocks. What does this pattern indicate about stress on faults?
Stress continues to adjust along faults after a mainshock, causing aftershocks
Given the USGS map: which 3 large cities are at risk for volcanic mudflows
Camas, Washougal, Troutdale
How old are Mr. Jackson and Mr. McKinney?
73
Where is the San Andreas Fault located
California
What are the three types of Volcanic threats?
extinct, dormant, active
Explain why scientists generally cannot predict the exact time and magnitude of an earthquake, and why they instead produce hazard maps
Exact timing is unpredictable because of complex fault behavior and insufficient precursors; hazard maps show past, events, rates, and tectonics to show relative risk
Given the USGS map: Which lake would be effected by regional lava flows?
Timothy Lake
What is the name of the river that serves as the border between Oregon and Washington
The Columbia