View source for UCVM ucvm with sw4 using cvmsi

== Question ==

Question from Rei to Scott,

..conducting SW4 simulations within the LA Basin for both small and large magnitude earthquake events 
(please see the attached slides for reference where we are interested in). While validating the ground 
motions, we have come across several features in the velocity model—built from the SCEC model—that we 
were hoping to better understand with your insight.

Blocky structure north of LA (highlighted in red in the slides):
  We observed a blocky structure characterized by elevated Vs compared to the surrounding region. This structure appears to disappear at 50 m depth and then re-emerges below. Is there a specific reason why this structure is not present at the 50 m depth level?

Vp–Vs relationship of the blocky structure (green color):
  The structure shows higher Vs values, with Vp appearing higher at the surface (Z = 0 m) but becoming lower at 250 m depth. We also noted that the density is relatively low at the surface. 

Vp–density relationship west of the blocky structure:
  In this nearby region, the density is higher than that of the surrounding material, but Vp appears to be lower. (I expect Vp correlates with density)

Would you know of any literature or documentation that describe these characteristics?

== Background of the posted question ==

Accessing UCVM velocity model via SW4's UCVM reader branch and then run the SW4 simulation.

  CVM-S4.26.M01 (cvmsi), the velocity values are extracted using UCVM "withSCPBR" branch

internal query parameters were:

  ucvm_query -f conf/ucvm.conf -m cvmsi,elygtl:taper -L 200,700,1500

Is this version of velocity model, recommended for ground motion simulation ? (another question)

== Plots from explorer with the posted parameters ==

{|
| [[FILE:sw4_cvmsi_taper_200_map.png|thumb|300px|cvmsi taper200 map]] 
|}

{|
| [[FILE:sw4_cvmsi_taper_200_0m.png|thumb|300px|cvmsi taper200 0m]] 
| [[FILE:sw4_cvmsi_taper_200_50m.png|thumb|300px|cvmsi taper200 50m]]
| [[FILE:sw4_cvmsi_taper_200_100m.png|thumb|300px|cvmsi taper200 100m]]
| [[FILE:sw4_cvmsi_taper_200_250m.png|thumb|300px|cvmsi taper200 250m]]
|}

{|
| [[FILE:sw4_cvmsi_taper_200_line1_map.png|thumb|300px|cvmsi taper200 line1]] 
| [[FILE:sw4_cvmsi_taper_200_line1.png|thumb|300px|cvmsi taper200 line1]]
| [[FILE:sw4_cvmsi_taper_200_line2_map.png|thumb|300px|cvmsi taper200 line2]]
| [[FILE:sw4_cvmsi_taper_200_line2.png|thumb|300px|cvmsi taper200 line2]]
|}

{|
| [[FILE:sw4_cvmsi_taper_200_line3_map.png|thumb|300px|cvmsi taper200 line3]] 
| [[FILE:sw4_cvmsi_taper_200_line3.png|thumb|300px|cvmsi taper200 line3]]
|}

{|
| [[FILE:sw4_cvmsi_taper_200_pt_map.png|thumb|300px|cvmsi taper200 pt]] 
|}

{|
| [[FILE:sw4_cvmsi_taper_200_pt1.png|thumb|300px|cvmsi taper200 pt1]] 
| [[FILE:sw4_cvmsi_taper_200_pt2.png|thumb|300px|cvmsi taper200 pt2]]
| [[FILE:sw4_cvmsi_taper_200_pt3.png|thumb|300px|cvmsi taper200 pt3]]
| [[FILE:sw4_cvmsi_taper_200_pt4.png|thumb|300px|cvmsi taper200 pt4]]
|}

== Base cvm ==

{|
| [[FILE:sw4_cvms_0m.png|thumb|300px|cvms 0m]] 
| [[FILE:sw4_cvms5_0m.png|thumb|300px|cvms5 0m]]
| [[FILE:sw4_cvmsi_0m.png|thumb|300px|cvmsi 0m]]
|}

{|
| [[FILE:sw4_cvmsi_50m.png|thumb|300px|cvmsi 50m]] 
| [[FILE:sw4_cvmsi_100m.png|thumb|300px|cvmsi 100m]]
| [[FILE:sw4_cvmsi_250m.png|thumb|300px|cvmsi 250m]]
|}

{|
| [[FILE:sw4_cvmsi_all_0m.png|thumb|300px|cvmsi all 0m]] 
| [[FILE:sw4_cvmsi_all_50m.png|thumb|300px|cvmsi all 50m]]
| [[FILE:sw4_cvmsi_all_100m.png|thumb|300px|cvmsi all 100m]]
| [[FILE:sw4_cvmsi_all_250m.png|thumb|300px|cvmsi all 250m]]
|}

looking at basin,

{|
| [[FILE:sw4_cvmsi_basin_a.png|thumb|300px|cvmsi basin a]] 
| [[FILE:sw4_cvmsi_basin_b.png|thumb|300px|cvmsi basin b]]
|}

== using elygtl:ely ==

{|
| [[FILE:sw4_cvmsi_ely0_0m.png|thumb|300px|cvmsi ely0 0m]]
|}