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ImageThoughtsFurther Interrogation
South island comparison for 200m (cs 20p6 + cs 20p5 + ds) vs 400m (cs 20p4 + cs 20p5 + ds)

No notable HF differences (given the color bar discretization), despite re-run (different seed) and slightly larger domains.None needed

pSA 3.0 was HF in 400m and LF in 200m

Basins in canterbury, malborough and nelson show increased IM level.

Red is southland / Westcoast? (Ethans comment, no basins in the sims here)

(Ethan's comment, as pSA 3.0 was HF in one sim and LF in the other, the trend shows that the LF sim results in a lower hazard following the alpine range in the SI, while in general the LF has a higher hazard in Canterbury and other modelled basins. This is due to basin amplification at in these regions (the HF sim is simplified physics and does not amplify these frequencies like the LF sim does. In summary, the blue down the spine is more due to the difference between HF and LF sim techniques (B: specifically around the rock areas) and not the location of the hazard, while the red in the basins is due to the LF sim amplifying specific wave frequencies in these regions)

Zoomed in plots in basin areas. Can probably plot Waiau, Cheviot and Hanmer basin regions on a single plot, Marlborough and Nelson also in close proximity (approx region shown in figure) IMs at the transition frequency will show the most variability. pSA1.0-5.0, PGV (others useful to look at though)

pSA over transition frequency



Cheviot / Hanmer / Waiau



Marlborough / Nelson




Christchurch



pSA 5.0 is LF in both 400m and 200m

General increase in this IM across whole SI






19p5 (CS19p5 + subduction sampling + txt based empirical) vs v20p4 (CS20p4 + CS20p5 + DS (Bradley + BC Hydro))


DS model for Christchurch updated for the increased aftershock probabilitiesZoomed in Chch / Banks Peninsula (can see a trend in this region) IMs of interest pSA < 2s, PGA, PGV as DS expected to have larger influence on HF - useful to see all IMs though.

Waikato Basin introduced in 20p4 (increased in these areas)

Hikurangi changed to simulation (decreased)


Zoomed Waikato basin plot (approx region shown in figure) All IMs are of interest. 
Christchurch



Waikato




General guide to the locations of basins characterized in the NZVM. Basin boundary text files can be found in https://github.com/ucgmsim/Velocity-Model/tree/development/Data
Further plots? Empirical vs 20p4?



Not sure if this is necessary. I think we are targeting identifying the differences between cybershake versions (if its easy to do this then emp vs sim for all the basins would be good to look at also)
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