A model for earthquakes near Palisades Reservoir, southeast Idaho

Schleicher, David

Abstract:

The Palisades Reservoir seems to be triggering earthquakes: epicenters are concentrated near the reservoir, and quakes are concentrated in spring, when the reservoir level is highest or is rising most rapidly, and in fall, when the level is lowest. Both spring and fall quakes appear to be triggered by minor local stresses superposed on regional tectonic stresses; faulting is postulated to occur when the effective normal stress across a fault is decreased by a local increase in pore-fluid pressure. The spring quakes tend to occur when the reservoir level suddenly rises: increased pore pressure pushes apart the walls of the graben flooded by the reservoir, thus decreasing the effective normal stress across faults in the graben. The fall quakes tend to occur when the reservoir level is lowest: water that gradually infiltrated poorly permeable (fault-gouge?) zones during high reservoir stands is then under anomalously high pressure, which decreases the effective normal stress across faults in the poorly permeable zones.

Genre:

Article

ProdID:

70042868

Citation Author:

Schleicher, David

Citation Contributing Office:

Earthquake Science Center

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

400

Citation Issue:

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

Journal of Research of the U.S. Geological Survey

Citation LatN:

49.0

Citation LatS:

42.0

Citation LonE:

-111.04

Citation LonW:

-117.24

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

8 p.

Citation Projection:

Citation Public Comments:

Citation Publisher:

U.S. Geological Survey

Citation Series:

Citation Series Code:

Citation Series Number:

Citation Search Results Text:

A model for earthquakes near Palisades Reservoir, southeast Idaho; 1975; Article; Journal; Journal of Research of the U.S. Geological Survey; Schleicher, David

Citation Start Page:

393

Citation Volume:

Citation Year:

1975

Type:

citation/reference

Text:

A model for earthquakes near Palisades Reservoir, southeast Idaho; 1975; Article; Journal; Journal of Research of the U.S. Geological Survey; Schleicher, David