Shortly after Lake Mead (the reservoir impounded by Hoover Dam) began to fill, local earthquakes were felt. The earthquakes reached a culmination in a magnitude 5 earthquake about a year after the reservoir had filled to 80 percent capacity. For a number of years thereafter, small local earthquakes showed a close correlation in numbers and energy release with seasonal peak loads. In due time the correlation was as close with unloading as with loading. Sometimes there was no direct correlation at all.
In recent years many instances of local earthquakes attributed to crustal unbalance have been noted. Noteworthy is...
Figures & Tables
Prepared by the Case Histories Committee for the Engineering Geology Division of the Geological Society of America, these histories are intended as reference material for the practicing geologist and for the college student. This volume, the eighth in the Case History series, presents the seismological aspects of the works of man—the civil engineer or engineering geologist interacting with the environment. Topics are in two categories—changes at a point (nuclear or chemical explosions and well injection or withdrawal) and changes on a line (damming a river or construction along a coastline).