Diablo Canyon SSHAC Level 3 Study

Transcription

1 1 Diablo Canyon SSHAC Level 3 Study Workshop 1 Summary of SSC Hazard Significant Issues and Data Needed William Lettis November 29 to December 1, 2011 PG&E DCPP SSHAC Study

2 2 Hosgri Hosgri Location Hosgri Hosgri Rupture Length Shoreline Los Osos Los Osos San Luis Bay San Luis Bay Los Osos C. Thickness San Luis Bay Rup Length Shoreline Length Los Osos Rup Length SLB C. Thickness Hosgri Joint Ruptures Summary of SSC Sensitivity: PGA

3 SSC Data Needs & Hazard Sensitive Issues 3 Hosgri Hosgri Loc. Rup. Shoreline Los Osos Los Osos San Luis X X X X Seismic Reflection X X X MBES data X X Paleoseismic data Data Gaps and Needs X X X OBS / seismic network X X X Recurrence models and magnitude PDF studies X X Onshore marine terrace mapping X X X X X Regional Tectonics/Kinematics X X X X X X Process for Data Evaluation/Documentation X X X X Offshore terrace/geologic mapping X X Onshore geologic mapping

4 SSC Data Needs & Hazard Sensitive Issues 4 Hosgri Hosgri Loc. Rup. Shoreline Los Osos Los Osos San Luis Data Gaps and Needs X X X Geochronologic studies X X X Potential field data / sampling X X X X X X Data sharing / availability X X X Recurrence models and magnitude PDF studies X X Onshore marine terrace mapping X X X X X Regional Tectonics/Kinematics X X X X X X Process for Data Evaluation/Documentation X X X X Offshore terrace/geologic mapping X X X Onshore geologic mapping

5 SSC Summary of Data Needs 1. Improve seismic network coverage two gaps onshore, all of offshore - 4 OBEs and 4 temporary OBEs are planned in DCPP vicinity. Jeannie suggests additional offshore deployment of OBEs to cover Santa Lucia Bank fault, offshore Purisima, Lompoc, Queenie structures, etc. Nishenko suggests development of OBE swat team to respond to earthquakes that occur. 3. Use geophysics energy sources for improvements to velocity model - important for relocation of seismicity 4. Consider offshore GPS instrument locations - ocean bottom - Pecho Rock 5. Improve understanding of San Andreas fault slip rates - important for plate motion discrepancy analysis - Lisa Grant, Ramon Arrowsmith, Ray Weldon 6. Improve plate motion resolution west of San Andreas Fault - Sarah Titus et al; Reoccupy campaign GPS stations 7. Improve understanding of seismic lineations in Estero Bay 8. Recurrence models consider time dependent or renewal models 5

6 SSC Summary of Data Needs 9. Hanson - GIS Documentation for SSHAC establish protocol 10. Johnson - Availability of GIS Data Base 11. Rikk - Multi-beam bathymetry fill in white zones, Hosgri trace across Estero Bay, shelf break; ship-based coastal LiDAR. 12. Page - Offshore marine Terrace mapping date relict marine sediments, in areas of sediment coverage obtain seismic coverage, for fault evaluations identify offset features followed by collection of detailed 3d seismic chirp data 13. Johnson - USGS will perform sled surveying, and may be able to help identify sites for surgical sampling 14. Hanson Nipomo Mesa has possible terraces below sea level that we may be able to sample 15. LiDAR additional data along San Simeon fault and Cambria fault, if needed 16. Johnson Fugro Pelagos flew coastal LiDAR in 2009 for ACOE and flew bathymetric LiDAR in 2011 (our initial analysis suggests that data are not of good quality in DCPP area). 17. NOAA onshore/offshore topography/bathymetry correlation tool 6

7 SSC Summary of Data Needs 18. Langenheim Possibly improve magnetic data from Estero Bay (closer line spacing or helicopter mag.). Gravity marine data could be improved. More site-specific constraints on physical properties (Sonic logs, density logs, borehole gravity, remanent magnetization of ophiolite) 19. Mooney - Targeted analysis of seismic lines to evaluate interpretation of potential field models 20. Lettis develop end member models that still fit the observed anomalies. 22. Nishenko seismic overview Lettis will it be possible to tweak the program to obtain additional seismic data in Estero bay? Answer yes until environmental impact report issued. 23. Mooney record air guns onshore. 24. Mooney legacy refraction data data gaps include a need for data to identify high-angle crustal faults, targeted seismic studies 25. Rietman legacy seismic reflection data. Data to constrain dip of Hosgri fault at depth, data to constrain slip rate on Hosgri fault. Data to constrain location and dip of Los Osos, San Luis Bay and other faults east of Hosgri. Data to characterize Hosgri San Simeon stepover. Data to identify potential tsunami sources east of the Hosgri 7

8 SSC Summary of Data Needs 26. Mooney how will legacy seismic reflection data be available? Walter suggests using IRIS to store data. 27. Greene scan analog legacy data. 28. Rietman Use archived legacy data in kingdom suite SMT with newly acquired data. 29. Caskey Heat flow data may be useful for evaluating deeply rooted flower structures into mafic oceanic crust. 30. Johnson presentation re-highlights need for multibeam data in Estero Bay, need multibeam mapping of shelfbreak for landslide/tsunami analysis (may also be important for identifying geomorphic channels that may cross Hosgri). Can we sample sediment for event stratigraphy 31 Hogan presentation Geochronologic control on buried paleochannels at south end of Shoreline fault. Data gaps Estero Bay fault geometry, San Luis Bay fault geometry, Hosgri fault slip rates, San Simeon Hosgri stepover area, shoreline fault slip rates, shoreline fault termination/truncation fault linkages. 32. Processing steps try pre stack depth migration in addition to the time migration 8

9 SSC Summary of Data Needs 33. Age Control summary targets (1) marine terrace ages, (2) event stratigraphy in Hosgri basins, (3) paleochannels. 34. O Connell onshore 2D/3D seismic reflection program. Data needs future deployment of nodes on DCPP property for offshore energy shots plus return of vibroseis trucks 9

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11 11 Diablo Canyon SSHAC Level 3 Study Thank You PG&E DCPP SSHAC Study