1. Brian Chiou NGA Workshop July 19, 2004 NGA Dataset

2. Version 1 - November 2003 Version 2 – June 04, 2004 –Used for preliminary data analysis Version 3 – August, 2004 –Final

3. NGA Data Set –MasterEQ_V012 (include finite fault models for 62 earthquakes) –SourceScaling_ALL_V012 –NGA_Site_V017 –060104.cat (catalog of recordings) –…… Flatfile

4. Status of Data (07/15/2004) 173 earthquakes ~ 1600 strong-motion stations 3547 recordings –22 more records 16 USGS records (Stevens and Boore, USGS), Loma Prieta 3 records from Stone Canyon (Event 0139) Hector, Hector Mine earthquake Jensen Filter Plant Generator Bldg, Northridge earthquake TCU088 of ChiChi

7. Data Coverage Pre-NGA –EQID: 1 – 127 (1994 Northridge) –Total number of recordings = 1079 NGA –EQID: 1 – 175 –Total number of recordings = 3547 –Total number of ChiChi data = 1812

8. Previous Data New EQ Data - Kobe - Kocaeli - ChiChi - Duzce - Hector Mine - Denali

9. Histogram of Recordings - Distance

10. Histogram of Recordings - Mw

11. Data used for Extensional Regime

12. Recent Improvement on Source- Path Metadata Isochrone-directivity parameters (USGS Open File Report) 

13. Recent Improvement on Site Metadata  California/Nevada Review & revision of Geomatrix 3-letters classification (D. Wells, Geomatrix Consultants Inc.)  Alaska (Denali earthquake) –Geomatrix 3-letters classification (D. Wells, Geomatrix Consultants Inc.)

14. Recent Improvement on Site Metadata Vs30  Taiwan (ChiChi and aftershocks) –Measured Vs30 at 125 Sites (NCREE’s P-S logging) –Geomatrix 3-letters classification (D. Wells, Geomatrix Consultants Inc.) –Inferred Vs30

15. NEHRP-ANEHRP-B NEHRP-CNEHRP-DNEHRP-E Category Missing ChiChi & Aftershocks March, 2004

16. July, 2004 NEHRP-DNEHRP-E NEHRP-BNEHRP-A NEHRP-C

17. Recent Improvement on Site Metadata Basin depth information Z 1.5 = depth to the Vs=1.5km/sec isosurface  Bay Areas (J. Boatwright/USGS, Menlo Park)  Los Angels Areas, Imperial Valley, and Mendocino (Rob Graves, URS/John Stewart, UCLA)

18. Development of Ground Motion Parameters Strike-normal, strike-parallel, and vertical components –In progress (N. Abrahamson) PGA, PGV & PGD from data provider –Uncorrected (Vol. 1) & corrected (Vol. 2) PGA (CGS/USGS)

19. Recent Development of Ground Motion Metadata A simple (and conservative) rule to determine lowest usable frequency for spectral accelerations –Based on several factors: filter type, corner frequency, instrument type A more rigorous rule – D. Boore

23. Schedule Final release of NGA dataset: early August