The USGS database is a relational Oracle spatial database. Table C1 defines parameters in the database that were discussed previously, except for the geographic coordinates of the mapped features that are stored as Oracle spatial objects. The following table is not intended to depict the entire data model or to be exhaustive. The USGS database stores computational values as well as expert judgment values that are the foundation of the source model for each version of the national seismic hazard map. As such, the USGS seismogenic source model can be tested in its entirety for reproducibility and can provide customized input files for use in other applications.
| Field name | Variable | Description |
|---|---|---|
| CFAULT_OR | NUMBER | Unique alpha-numeric ID assigned to the record. |
| NAME | VARCHAR2(320 BYTE) | Seismogenic source name, modified from fault name. |
| EFFECTIVE_DATE | Date | Date of the most recent record update. |
| Field name | Variable | Description | Units |
|---|---|---|---|
| PREF_UPPER_DEPTH | VARCHAR2(320 BYTE) | Assigned value of the depth of the upper edge, from local topography. | kilometer |
| PREF_LOWER_DEPTH | VARCHAR2(320 BYTE) | Assigned value of the depth of the lower edge, from local topography. | kilometer |
| PREF_DIP | VARCHAR2(320 BYTE) | Assigned dip angle between 0 and π/2 from horizontal. | degree |
| PREF_RAKE | VARCHAR2(320 BYTE) | Assigned rake according to Aki and Richards (1980) definition. The direction the hanging wall moves during rupture, measured relative to the fault strike (between -180 and 180 degrees). | degree |
| FAULT_PAR_SR; CALC_FAULT_PAR_SR | NUMBER | Assigned slip as a function of time resolved to the dipping surface of the fault. | mm/yr |
| CALC_WIDTH | NUMBER | Width of source calculated from PREF_UPPER_ DEPTH, PREF_LOWER_DEPTH, and PREF_DIP. |
kilometer |
| CALC_LENGTH | NUMBER | Length of source calculated from the map objects. | kilometer |
| CALC_WC_MAG_L; CALC_HB_MAG; CALC_ELLS_MAG | NUMBER | Calculated earthquake magnitude based on published regression equations (in moment magnitude, M). WC, Wells and Coppersmith (1994); HB, Hanks and Bakun (2002); ELLS, Ellsworth (2003). | scalar |
| PREF_ASEISMIC_SLIP | NUMBER | Assigned aseismic slip factor. |
Aki, K., P. G. Richards (1980). Quantitative Seismology, Theory and Methods, vol. I, 557 pps. San Francisco: W.H. Freeman and Company.
Ellsworth, W., 2003, "Appendix D—Magnitude and area data for strike slip earthquakes",in Working Group on California Earthquake Probabilities, Earthquake Probabilities in the San Francisco Bay Region— 2002–2031. U.S. Geological Survey Open-File Report03–214, 6pps.
Hanks, T. C., and W. H. Bakun (2002). A bilinear source-scaling model for M–log A observations of continental earthquakes. Bulletin of the Seismological Society of America 92, 1841–1846.
Wells, D. L., and K. J. Coppersmith (1994). New empirical relationships among magnitude, rupture length, rupture width, and surface displacements. Bulletin of the Seismological Society of America 84, 974–1002.
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