Conclusions Table of Contents Geologic Hazards

NEHRP Tasks Assigned to the USGS

The following Tasks assigned to the U.S. Geological Survey are numbered sequentially from the original NEHRP Strategy Document of March 14, 1994. These Task numbers correspond with those numbers listed in parentheses following the Selected Bibliography citations (p. 80).

1 Develop GIS hazard maps that incorporate site amplification and ground failures
2 Support immediate seismological, geodetic, and geological fieldwork to collect perishable data from the Northridge earthquake.
3 Conduct quantitative inventory of damage and intensity
4 Undertake geophysical and geological investigations of the elucidate regional fault structures
5 Study details of the Northridge rupture process
6 Clarify different contributions of the earthquake source from site and path effects in the strong-motion records
7 Collect and analyze geological and geophysical data for understanding of recurrences of earthquakes in the San Fernando Valley
8 Analyze 3-dimensional character of the San Fernando Valley and monitor changes with geodetic surveys, such as GPS
9 Improve broadband and strong-motion instrumentation to record larger aftershocks
10 Conduct systematic studies of shaking amplification caused by the San Fernando sedimentary basin
11 Undertake detailed seismic experiments to image the basin structures of the San Fernando Valley, Los Angeles, and San Bernardino areas
12 Study local site effects of seismic waves on a block-by-block scale
13 Categorize local site response by shallow shear-wave velocity measurements
14 Study and characterize nonlinear amplification of ground motion
15 Investigate causes of high-amplitude shaking in Tarzana
16 Examine local amplification effects at collapsed freeway sites
17 Evaluate the role of ground failure on disruption of lifelines
18 Produce realistic time histories of ground motions from scenario earthquakes
19 Produce local site-response maps
20 Produce regional seismic-hazards maps
21 Conduct coordinated geological and geotechnical investigations to determine shaking and deformation at failed freeway structures
22 Determine variation of ground shaking in terms of source, propagation and site effects
23 Evaluate the performance of earth slopes and earth-retaining structures
24 Study the liquefaction and ground-displacement data for validating methods of predicting liquefaction hazards
25 Study level of performance at sites where ground improvement techniques were used
26 Investigate ground motions that contributed to the large movements in buildings
27 Study the dynamic behavior and performance of instrumented buildings
28 Provide data to support loss-estimation methodology
29 Determine how effects of this earthquake influence hazard and risk maps
30 Investigate damage and vulnerability patterns from Northridge and 1971 San Fernando earthquakes
31 Apply econometric model for predicting losses from earthquakes in the San Fernando and Los Angeles basins
32 Contribute to comprehensive NEHRP report on the Northridge earthquake
33 Examine incentives for reduction of earthquake risk
34 Improve capabilities to disseminate information in near real-time
35 Develop documents of use to other regions regarding new insights in seismic hazards

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