Location

San Diego, California

Session Start Date

3-26-2001

Session End Date

3-31-2001

Abstract

The campus of the College of the Redwoods is located completely within the Little Salmon Fault Zone, designated by the State of California as an active fault. The College has been extensively investigated for fault rupture and other seismic hazards in 1989, 1993, 1997, 1998, and 1999. The Little Salmon Fault Zone bounds the College and consists of two main northwest-striking, northeastdipping, low-angle thrusts. The west splay daylights along the southwest edge of the campus and projects beneath it. A recurrence interval of 268 years and slip rate of 5+/-3 mm/yr is estimated by CDMG. Individual dip-slip displacements along the west trace are reported to be 12 to 15 feet (3.6 to 4.5 m). Movement on the Little Salmon fault (LSF) is accompanied by growth of broad asymmetric folds in the upper thrust sheet resulting in surface rupture, localized uplift and discreet fault-bend fold axial surfaces. College of the Redwoods is located approximately 8 miles (13 km) south of Eureka and 25 miles (40 km) north-northeast of Cape Mendocino and the Mendocino Triple Junction (MTJ) in northern California. The 'MTJ is the point of transition fi-om strike-slip faulting of the San Andreas transform system to low-angle thrust faulting and folding associated with the convergent margin of the Cascadia Subduction Zone. Campus infrastructure is located along the base of the Humboldt Hill Anticline (HHA), a major faultbend fold of the Cascadia fold and thrust belt. A new learning resource center (LRC) is proposed for a location 400 feet (120 m) northeast of where the west trace of the LSF daylights and 200 feet (60 m) above the low-angle fault plane. Building setback and design recommendations to mitigate for both fault rupture hazards and fault-generated folding hazards are presented.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Meeting Name

Fourth Conference

Publisher

University of Missouri--Rolla

Publication Date

3-26-2001

Document Version

Final Version

Rights

© 2001 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Mar 26th, 12:00 AM Mar 31st, 12:00 AM

Use of Microzonation to Site Facility on Low Angle Thrust and Associated Fault Bend Folding

San Diego, California

The campus of the College of the Redwoods is located completely within the Little Salmon Fault Zone, designated by the State of California as an active fault. The College has been extensively investigated for fault rupture and other seismic hazards in 1989, 1993, 1997, 1998, and 1999. The Little Salmon Fault Zone bounds the College and consists of two main northwest-striking, northeastdipping, low-angle thrusts. The west splay daylights along the southwest edge of the campus and projects beneath it. A recurrence interval of 268 years and slip rate of 5+/-3 mm/yr is estimated by CDMG. Individual dip-slip displacements along the west trace are reported to be 12 to 15 feet (3.6 to 4.5 m). Movement on the Little Salmon fault (LSF) is accompanied by growth of broad asymmetric folds in the upper thrust sheet resulting in surface rupture, localized uplift and discreet fault-bend fold axial surfaces. College of the Redwoods is located approximately 8 miles (13 km) south of Eureka and 25 miles (40 km) north-northeast of Cape Mendocino and the Mendocino Triple Junction (MTJ) in northern California. The 'MTJ is the point of transition fi-om strike-slip faulting of the San Andreas transform system to low-angle thrust faulting and folding associated with the convergent margin of the Cascadia Subduction Zone. Campus infrastructure is located along the base of the Humboldt Hill Anticline (HHA), a major faultbend fold of the Cascadia fold and thrust belt. A new learning resource center (LRC) is proposed for a location 400 feet (120 m) northeast of where the west trace of the LSF daylights and 200 feet (60 m) above the low-angle fault plane. Building setback and design recommendations to mitigate for both fault rupture hazards and fault-generated folding hazards are presented.