updated_BayArea_and_LA_basins

This merge request addresses issue #35 (closed).

Brad Aagaard provided updated Bay Area and Los Angeles basin polygons and Zx data files. I did some minor reformatting of the geojson files, changed file names to our current format, and added them to the site-data/basin directory.

Attached are 2% in 50-year PE ground motion comparisons for a variable VS30 at 0.2, 1, and 5s SA. The comparisons show changes in hazard using these updated polygons and Zx data vs. the 2018 NSHM. The updated polygons are shown as solid black lines, while the 2018 polygons are shown as dashed black lines:

plot_CA_2023_vs_2018_varaible_0p2_2pc50_difference_ratio_maps.pdf

plot_CA_2023_vs_2018_varaible_1p0_2pc50_difference_ratio_maps.pdf

plot_CA_2023_vs_2018_varaible_5p0_2pc50_difference_ratio_maps.pdf

No changes can be seen at 0.2s SA, as our basin amplification model does not start until 0.75s SA.

At 1 and 5s SA, we can see basin amplification in the Bay Area, the new Central Valley basin, and Los Angeles. Hazard changes in the Bay Area are the result of an updated polygon and Zx data. Changes are especially prominate in the East Bay (lower in 2023), and where the update polygon has extended to the west (higher in 2023). Hazard changes in Los Angeles (lower) are minor, as that Zx model did not change much:

plot_bay_area_2023_vs_2018_varaible_1p0_2pc50_difference_ratio_maps.pdf

plot_bay_area_2023_vs_2018_varaible_5p0_2pc50_difference_ratio_maps.pdf

plot_los_angeles_2023_vs_2018_varaible_1p0_2pc50_difference_ratio_maps.pdf

plot_los_angeles_2023_vs_2018_varaible_5p0_2pc50_difference_ratio_maps.pdf