A fault zone that is known for a lot of big and small earthquakes goes suddenly quiet for 10 years. This quiet period in an otherwise active fault zone is called a seismic gap
Explain why seismic gaps are pretty good indicators that an area may soon have a moderate or large earthquake. (Hint: Think of strain in rocks.)
The history of activity suggests that this is a geologically active area with a great deal of rock movement underground. The previous quakes have released the strain in the rocks as it has built up. The seismic gap indicates that sections of rock have been stuck together for some time without slipping and releasing strain. Like a deformed spring, the rocks are storing energy. As the rock continues to deform without slipping, the stored energy grows. When friction lets go, the rock could slip–an earthquake.
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All of the following statements about solid biomass are correct except
a. plantations can help restore degraded areas b. costs are moderate c. they are widely available in some areas d. they are possible to produce with no net carbon dioxide increase e. it can lead to deforestation
The Gulf of Mexico is located at an active margin
a. True b. False
In order to reduce your waste disposal footprint, you might ________
A) consider purchasing disposable items B) recycle nothing C) use organic fertilizers instead of manure or recycled sludge D) throw away everything E) give attention to reuse, recycle, and reduce
Endogenic processes:
a. originate on Earth's surface. b. decrease relief. c. include tectonic processes. d. include erosion. e. include weathering.