CyberShake Study 20.5 - Revision history

Scottcal at 19:48, 8 July 2022

2022-07-08T19:48:58Z

2020-12-03T22:45:38Z

Velocity Model

2020-12-03T22:39:09Z

Velocity Model

2020-12-03T22:38:55Z

Velocity Model

2020-12-03T22:38:09Z

Velocity Model

2020-12-03T22:36:27Z

Velocity Model

2020-12-03T22:32:43Z

Velocity Model

2020-12-03T22:27:55Z

2020-10-28T05:38:44Z

Seismograms

2020-08-19T23:31:50Z

Impulse modifications

← Older revision		Revision as of 19:48, 8 July 2022
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−	CyberShake Study 20.5 is a CyberShake study in Southern California which uses [[Rupture_Variation_Generator_v5.4.2\|Graves & Pitarka (2019)]] and includes stochastic high frequencies using the Graves & Pitarka high-frequency module from the SCEC Broadband Platform.	+	CyberShake Study 20.5 is a proposed CyberShake study in Southern California which uses [[Rupture_Variation_Generator_v5.4.2\|Graves & Pitarka (2019)]] and includes stochastic high frequencies using the Graves & Pitarka high-frequency module from the SCEC Broadband Platform.

	== RotD code verification ==		== RotD code verification ==

@@ Line 164: / Line 164: @@
 Therefore, we have added the capability of using an arbitrary depth, represented as a fraction of a grid point, when querying UCVM to populate surface mesh points.
-Here is a comparison of hazard curves using z=0 to populate the mesh points (Run 7130), and z=h/4 (25m) (Run 7133):
+Here is a comparison of hazard curves for site USC using z=0 to populate the mesh points (Run 7130, in <span style="color:blue">blue</span>), and z=h/4 (25m) (Run 7133, black).  Since we are slightly increasing the velocity of the surface point, we would expect slightly lower hazard, which is what we see.
 {| border="1"

@@ Line 127: / Line 127: @@
 Some locations, especially in CVM-S4.26.M01, have a sharp transition between the velocity at the surface and the velocity a few meters down.  For example, at site PAS (34.14826, -118.17119):
 {|
@@ Line 157: / Line 159: @@
 | 100.0 || 1500.181
 |}
 The surface mesh point is supposed to represent the velocities from 0 to h/2, where h is the grid spacing.  This is 50m for Study 20.5. But for a site like PAS Vs=309 is a poor representative value.  Vs30, calculated using a slowness average, is 839, and Vs50 is 993.

@@ Line 158: / Line 158: @@
 |}
-[[File:PAS_Vs_profile.png]]
+[[File:PAS_Vs_profile.png|right]]
 The surface mesh point is supposed to represent the velocities from 0 to h/2, where h is the grid spacing.  This is 50m for Study 20.5. But for a site like PAS Vs=309 is a poor representative value.  Vs30, calculated using a slowness average, is 839, and Vs50 is 993.

@@ Line 164: / Line 164: @@
 Therefore, we have added the capability of using an arbitrary depth, represented as a fraction of a grid point, when querying UCVM to populate surface mesh points.
-Here is a comparison of hazard curves using z=0 to populate the mesh points, and z=h/4 (25m):
+Here is a comparison of hazard curves using z=0 to populate the mesh points (Run 7130), and z=h/4 (25m) (Run 7133):
-{|
+{| border="1"
 == Output Data Products ==

← Older revision		Revision as of 22:32, 3 December 2020
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	\|}		\|}

		+	The surface mesh point is supposed to represent the velocities from 0 to h/2, where h is the grid spacing. This is 50m for Study 20.5. But for a site like PAS Vs=309 is a poor representative value. Vs30, calculated using a slowness average, is 839, and Vs50 is 993.
		+
		+	Therefore, we have added the capability of using an arbitrary depth, represented as a fraction of a grid point, when querying UCVM to populate surface mesh points.
		+
		+	Here is a comparison of hazard curves using z=0 to populate the mesh points, and z=h/4 (25m):
		+
		+	{\|

	== Output Data Products ==		== Output Data Products ==

@@ Line 123: / Line 123: @@
 | [[File:10sec_rvfrac_random_weighted_zoomed.png|thumb|300px]]
 |}
 == Output Data Products ==

@@ Line 128: / Line 128: @@
 === Seismograms ===
-* Deterministic (dt=0.05, nt=8000)
+* Deterministic (dt=0.05, nt=10000)
-* Broadband (dt=0.01, nt=40000)
+* Broadband (dt=0.01, nt=50000)
 === Intensity Measures ===

@@ Line 53: / Line 53: @@
 We discovered that the current impulse used as input to the SGT simulations, which has a tdelay of 1 second (meaning that the peak occurs at t=1 sec), results in artificial truncation of some of the impulse lobes.  To correct this, we changed tdelay to 3 seconds in both the impulse generator and the code which populates the SGT headers, so that it is handled correctly during synthesis.  This produces more complete impulses, with an integral closer to normalized 1.
-[[File:tdelay_impulse_comparison.png|thumb|600px]]
+{|
 == Conditional Hypocenter Distributions ==