Information presented in the passage suggests that, compared with seismic activity at the epicenter of a shallow event, seismic
activity at the epicenter of a deep event is characterized by (A) shorter P-S intervals and higher peak intensity
(B) shorter P-S intervals and lower peak intensity
(C) longer P-S intervals and similar peak intensity
(D) longer P-S intervals and higher peak intensity
(E) longer P-S intervals and lower peak intensity
Option E: longer P-S intervals and lower peak intensity.
Explanation:
It was Kiyoo Wadati (Japanese seismologist) who researched about shallow and deep earthquakes and it was based on his research Charles Richter developed his earthquake magnitude scale in 1935. Instead of relying upon arrival time of seismic waves at different location, he focused on time difference between arrival of primary waves and secondary waves (slower than primary waves). He discovered that during shallow earthquake interval was short near the epicenter and shaking was strongest that means higher peak intensity, whereas, when the earthquake was of deep focus the interval between P-S waves increases and hence will have lower intensity.
