SW4 Mesh Development
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Jump to navigationJump to searchGoal: Create NorCal CyberShake Mesh for SW4
Contents
Mesh Region
Region should match the SFBR model https://www.usgs.gov/programs/earthquake-hazards/science/3-d-geologic-and-seismic-velocity-models-san-francisco-bay
- ne_coord (-122.562365, 39.174505)
- nw_coord (-123.858493, 38.424179)
- sw_coord (-121.922036, 36.320331)
- se_coord (-120.644051, 37.050062)
- spacing=25.0
Config Script
- input 4 corners (and projection) and spacing
- calc rotation angle
- distance between points
- calculate nx, ny, nz based on spacing
Define Region
- origin
- rotation angle
- distance x
- distance y
- distance z
- spacing
Low Res UCVM2Mesh Configuration for SFBR Model
To test our mesh formats for SW4, we will test with a low resolution
- rot=-53.9
- x0=-123.858493
- y0=38.424179
- z0=0.0
- spacing=500.0
- Dist x = 140,000
- Dist y = 290,000
- Dist z = 40,000
- nx=280
- ny=580
- nz=80
Full Res UCVM2Mesh Configuration for SFBR Model
- rot=-53.9
- x0=-123.858493
- y0=38.424179
- z0=0.0
- spacing=25.0
- Dist x = 140,000
- Dist y = 290,000
- Dist z = 60,000
- nx=
- ny=
- nz=
Example from CyberShake
We don't actually generate a ucvm2mesh config file as part of the process of creating CyberShake meshes, but I've created what I think is the correct ucvm2mesh file for USC. The rotation angle is -55 degrees, and the 4 corners should be about:
-122.46716 34.52173 (x= 0.000 y= 0.000) -119.66138 37.97316 (x= 460.000 y= 0.000) -113.59525 34.44267 (x= 460.000 y= 672.000) -116.52591 31.13175 (x= 0.000 y= 672.000)
Rob might use a different projection system, so I'd only expect the corners to agree to 3 or so decimal places.