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J. Louie and L. Preston Nevada Seismological Laboratory S. Larsen

The Model Assembler Community Modeling Environment and Initial Ground-Motion Computations for Reno and Las Vegas. J. Louie and L. Preston Nevada Seismological Laboratory S. Larsen Lawrence Livermore National Laboratory Liz Lenox, Rei Arai, and Amr Wakwak

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J. Louie and L. Preston Nevada Seismological Laboratory S. Larsen

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  1. The Model Assembler Community Modeling Environment and Initial Ground-Motion Computations for Reno and Las Vegas J. Louie and L. Preston Nevada Seismological Laboratory S. Larsen Lawrence Livermore National Laboratory Liz Lenox, Rei Arai, and Amr Wakwak Dept. Geological Sciences and Engineering, UNR

  2. ModelAssembler • A code to stitch together existing regional geophysical and geological data sets. • Generates multi-gigabyte E3D input grids.

  3. The ModelAssembler Community Modeling Environment (MA-CME) • Graphical user interface for setting up MA/E3D “.in” files. • Provides tutorial help to successful setup. • Data sets, stations, grids all defined with geographic lat/lon (have to decide on WGS84, NAD27, etc.). • Easy configuration of problems at all scales and computational difficulties- 10 Mb to 100 Gb. • After setup, “portal pack” is downloaded to cluster and run. • Open source: www.seismo.unr.edu/ma • Limits: flat earth; no topography; 1-D variations within basins & bedrock; source and stations in same grid.

  4. MA-CME provides a tutorial GUI to E3DSet up a Grid:

  5. Define Earthquake Source

  6. Arrange Basin-Thickness (& Geotech) Inputs

  7. Basins in the B&R Four datasets, not well stitched together: • Geologic map with basin depths assumed from bedrock proximity, in California. • Jachens et al. USGS basin gravity inversions for Basin & Range; sedimentary plus Tertiary volcanic basins. • Abbott & Louie (2000) Reno basin gravity study. • Langenheim et al. Las Vegas model from gravity, refraction, a few deep wells.

  8. Request Output Data

  9. Reno 1) Genoa FZ M7.5 2) Frenchman M5.0 3) Furnace Cr FZ M7.5 Las Vegas Three Nevada Scenarios

  10. Genoa – Mount Rose Scenario:MA-CME adds Geotech & Basins Three datasets, not well stitched together around Reno or at Calif. Border.

  11. Genoa – Mount Rose Scenario:MA-CME adds Geotech & Basins Scott et al. (2004) Vs30 transect. Pancha measurements at ANSS stations. “Quadrant” interpolation between scattered measurements, respecting geologic map. Vs30=500 m/s assumed on sediment, 760 m/s (white and cyan) on rock.

  12. Genoa Fault – Mount Rose Fault Systems Dataset mismatches plain in model renderings. Extreme directivity effect. E3D computation at 0.3 Hz on a 120x200 grid with dh=500 m. Olsen and Day Q model included.

  13. Genoa Fault – Mount Rose Fault Systems West Reno basin, above end of rupture, has 5x the PGV of any other basin near fault. Highest shaking not correlated with basin depth- Tahoe artificially deep in this model. Dataset boundaries not interfering with these conclusions.

  14. Frenchman Mountain Fault Langenheim et al. model from gravity, refraction, a few deep wells.

  15. Frenchman Mountain Fault Scott et al. (2006) Vs30 model from 1100+ wells, 79 Vs profiles. Thanks to W. Taylor of UNLV & G. Wagoner of LLNL

  16. Frenchman Mountain Fault Animation combines inputs and outputs. E3D computation at 0.3 Hz on a 144x137 grid with dh=308 m. Grid resolution is a good match to cell phone displays.

  17. Frenchman Mountain Fault PGV >5 cm/s above west-dipping fault at 0.3 Hz. Sub-basins contain the greatest shaking.

  18. Northern Death Valley Fault Zone Jachens Basin & Range gravity inversions for sedimentary & volcanic basins. Timber Mtn. caldera & rifts up to 8 km deep. Langenheim et al. model from gravity, refraction, a few deep wells inserted for LVV.

  19. Northern Death Valley Fault Zone Jachens USGS geologic map sets default soil and rock Vs30s. Scott et al. (2006) Vs30 model from 1100+ wells, 79 Vs profiles inserted for LVV.

  20. No. Death Val. - Furnace Cr. Fault Zone Animation combines inputs and outputs. E3D computation at 0.3 Hz on a 281x251 grid with dh=1 km. Infinite Q. The two rupture scenarios have very different effects. Get the scenario animations on your cell phone from www.seismo.unr.edu/ma/

  21. Northern Death Valley Fault Zone For rupture toward city, PGV >1 cm/s in LVV. Clear directivity in this long-period simulation. Basins between DV and LVV are spreading the directivity effect to wider angles from the fault strike.

  22. Northern Death Valley Fault Zone Compare PGV of 2679 areas, each 1-km2, in LVV against Vs30 and Z2.0.

  23. Vs30 affecting 1.5-km waves! Northern Death Valley Fault Zone

  24. Northern Death Valley Fault Zone Uncertainty in PGV

  25. Conclusions • Students can use MA-CME to set problems up, but plotting and visualizing are still lots of work. • Scenario Results: • M7.5 Genoa–Mt. Rose– Reno basin at end of rupture gets 5 times the PGV of any other. • M5.0 Frenchman Mtn.– high PGV accompanied by short duration, concentrated by deep basin structure. • M7.5 No. Death Valley– rupture toward city produces up to 15 times the PGV as rupture away. • At long periods, 0.3 Hz, E3D is producing huge uncertainties in PGV.

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