Problem 3
The discovery of the potential for megathrust earthquakes on the Cascadia subduction zone is an example of how scientific explanations are developed. Briefly explain how the development of this hypothesis illustrated the following characteristics of scientific explanations: 1\. It was provisional (tentative). 2\. It was based on observations. 3\. It was predictable and testable. 4\. It offered a natural cause for natural events.
Problem 4
Are earthquake insurance rates based on inductive or deductive reasoning? Explain your choice. (Review information on inductive and deductive reasoning from Chapter 1 if necessary.)
Problem 5
An earthquake occurred on the Erie fault 5 kilometers ( 3 miles) beneath San Gabriel. Damage from the earthquake was greatest in nearby Fremont. The farthest report of shaking was recorded in Stockton. Where was the earthquake's epicenter? a) The Erie fault c) Fremont b) San Gabriel d) Stockton
Problem 7
If the San Andreas fault moves 2 meters ( \(6.6\) feet) per big earthquake, and plate movement is \(2.5\) centimeters (0.025 meter per year, or 1 inch per year), how many years of plate motion must accumulate to produce one big earthquake? (Assume all plate motion is accommodated by movements on the San Andreas fault.) a) 4 years b) 20 years c) 80 years d) 200 years
Problem 14
Three sites (L1, L2, L3) record earthquake magnitude and earthquake intensity for the same earthquake. \(\mathrm{Ll}\) is located closest to the focus and L3 is farthest away. Where is the intensity greatest, and what happens to the earthquake magnitude calculated at the different sites? a) Intensity is greatest at Ll; calculated magnitude is the same at each site. b) Intensity is greatest at L3; calculated magnitude is the same at each site. c) Intensity is greatest at Ll; calculated magnitude decreases with distance from the focus. d) Intensity is greatest at L3; calculated magnitude decreases with distance from the focus.
Problem 19
Warning times associated with some natural hazards can be measured in months (volcanoes), days (hurricanes), or minutes (tornadoes). Scientists in Japan have designed an earthquake warning system using an extensive network of seismographs. They use the arrival of \(P\) waves to trigger an alarm that can stop high-speed trains before the arrival of the more damaging \(S\) waves and the later surface waves. How would such a system affect citizens in a densely populated city such as Los Angeles that is situated near numerous active faults?
