CVM-SI - Revision history

Maechlin: Redirected page to CVM-S4.26.GTL

2016-01-28T06:18:01Z

Redirected page to CVM-S4.26.GTL

Maechlin at 06:17, 28 January 2016

2016-01-28T06:17:16Z

Davidgil: /* Interpolation Methods */

2014-02-14T18:52:47Z

Interpolation Methods

Davidgil: /* Interpolation Methods */

2014-02-14T18:52:28Z

Interpolation Methods

Davidgil: /* Starting Model */

2013-10-29T16:49:57Z

Starting Model

Davidgil at 16:47, 29 October 2013

2013-10-29T16:47:40Z

Davidgil: /* Interpolation Methods */

2013-06-18T05:13:21Z

Interpolation Methods

Davidgil: /* Interpolation Methods */

2013-06-18T05:13:06Z

Interpolation Methods

Davidgil: /* Interpolation Methods */

2013-06-06T06:01:12Z

Interpolation Methods

Davidgil: /* Interpolation Methods */

2013-06-06T05:36:12Z

Interpolation Methods

← Older revision		Revision as of 06:18, 28 January 2016
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−	[[CVM-S4.26.GTL]]	+	#redirect [[CVM-S4.26.GTL]]
	== Overview ==		== Overview ==

← Older revision		Revision as of 06:17, 28 January 2016
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		+	[[CVM-S4.26.GTL]]
	== Overview ==		== Overview ==

@@ Line 64: / Line 64: @@
 == Interpolation Methods ==
-This discussion pertains to an old model of CVM-SI. For the latest model, including a finalized interpolation method, please visit http://scec.usc.edu/scecpedia/CVM-S4.26_Proposed_Final_Model.
+'''This discussion pertains to an old model of CVM-SI. For the latest model, including a finalized interpolation method, please visit http://scec.usc.edu/scecpedia/CVM-S4.26_Proposed_Final_Model.'''
 The broad idea behind CVM-SI21 is that we can take the low resolution perturbation mesh and interpolate it onto the CVM-S model, which is rule-based and therefore arbitrary precision. However, since the perturbations were calculated using a Vs minimum of 1000m/s, in certain areas of CVM-S (like boreholes), doing a straight trilinear interpolation of the perturbations with the CVM-S material properties can result in negative Vs and/or Vp values.

← Older revision		Revision as of 18:52, 14 February 2014
Line 63:		Line 63:

	== Interpolation Methods ==		== Interpolation Methods ==
		+
		+	This discussion pertains to an old model of CVM-SI. For the latest model, including a finalized interpolation method, please visit http://scec.usc.edu/scecpedia/CVM-S4.26_Proposed_Final_Model.

	The broad idea behind CVM-SI21 is that we can take the low resolution perturbation mesh and interpolate it onto the CVM-S model, which is rule-based and therefore arbitrary precision. However, since the perturbations were calculated using a Vs minimum of 1000m/s, in certain areas of CVM-S (like boreholes), doing a straight trilinear interpolation of the perturbations with the CVM-S material properties can result in negative Vs and/or Vp values.		The broad idea behind CVM-SI21 is that we can take the low resolution perturbation mesh and interpolate it onto the CVM-S model, which is rule-based and therefore arbitrary precision. However, since the perturbations were calculated using a Vs minimum of 1000m/s, in certain areas of CVM-S (like boreholes), doing a straight trilinear interpolation of the perturbations with the CVM-S material properties can result in negative Vs and/or Vp values.

@@ Line 17: / Line 17: @@
 Step 1:
-. 3000.                             ! Minimum and corner of vp.
+. 3000.                             ! Minimum and corner of vp.<br />
-. 1500.                             ! Minimum and corner of vs.
+. 1500.                             ! Minimum and corner of vs.<br />
-. 2300.                             ! Minimum and corner of rho.(density)
+. 2300.                             ! Minimum and corner of rho.(density)<br />
-      read(*,*) modcvm(1),modcvm(2)
+read(*,*) modcvm(1),modcvm(2)<br />
-      read(*,*) modcvm(3),modcvm(4)
+read(*,*) modcvm(3),modcvm(4)<br />
-      read(*,*) modcvm(5),modcvm(6)
+read(*,*) modcvm(5),modcvm(6)<br />
 If I understand correctly, this means modcvm(1) contains the first value "2000", modcvm(2) contains "3000", modcvm(3) contains "1000", modcvm(4) = 1500, modcvm(5) = 2000, and modcvm(6) = 2300. Is this correct?
@@ Line 35: / Line 35: @@
 Then you would apply a sequence of formulas:
-    if(alpha(ii).lt.modcvm(2)) alpha(ii)=(modcvm(2)*(modcvm(1)-vpmin0)+alpha(ii)*(modcvm(2)-modcvm(1)))/(modcvm(2)-vpmin0)
+if(alpha(ii).lt.modcvm(2)) alpha(ii)=(modcvm(2)*(modcvm(1)-vpmin0)+alpha(ii)*(modcvm(2)-modcvm(1)))/(modcvm(2)-vpmin0)<br />
-    if(beta(ii).lt.modcvm(4)) beta(ii)=(modcvm(4)*(modcvm(3)-vsmin0)+beta(ii)*(modcvm(4)-modcvm(3)))/(modcvm(4)-vsmin0)
+if(beta(ii).lt.modcvm(4)) beta(ii)=(modcvm(4)*(modcvm(3)-vsmin0)+beta(ii)*(modcvm(4)-modcvm(3)))/(modcvm(4)-vsmin0)<br />
-    if(rho(ii).lt.modcvm(6)) rho(ii)=(modcvm(6)*(modcvm(5)-dnmin0)+rho(ii)*(modcvm(6)-modcvm(5)))/(modcvm(6)-dnmin0)
+if(rho(ii).lt.modcvm(6)) rho(ii)=(modcvm(6)*(modcvm(5)-dnmin0)+rho(ii)*(modcvm(6)-modcvm(5)))/(modcvm(6)-dnmin0)<br />
 So to translate into pseudocode, these three equations would be:
-If Vp < 3000 then Vp = (3000 * (2000 - Min_CVMS_Vp) + Vp * (3000 - 2000)) / (3000 - Min_CVMS_Vp)
+If Vp < 3000 then Vp = (3000 * (2000 - Min_CVMS_Vp) + Vp * (3000 - 2000)) / (3000 - Min_CVMS_Vp)<br />
-If Vs < 1500 then Vs = (1500 * (1000 - Min_CVMS_Vs) + Vs * (1500 - 1000)) / (1500 - Min_CVMS_Vs)
+If Vs < 1500 then Vs = (1500 * (1000 - Min_CVMS_Vs) + Vs * (1500 - 1000)) / (1500 - Min_CVMS_Vs)<br />
-If Rho < 2300 then Rho = (2300 * (2000 - Min_CVMS_Rho) + Rho * (2300 - 2000) / (2300 - Min_CVMS_Rho)
+If Rho < 2300 then Rho = (2300 * (2000 - Min_CVMS_Rho) + Rho * (2300 - 2000) / (2300 - Min_CVMS_Rho)<br />
 Finally, Step 4:
@@ Line 49: / Line 49: @@
 You would verify that if Vp/Vs was still less than 1.45 then we'd just set Vs = Vp / 1.45
-Please let me know if this is an accurate "summarized" version of how this model was built. I'm just looking to double check that I have everything right.
+I have uploaded our initial model to "/auto/rcf-104/pochen/CVM4".<br />
+The files are named by layer number.<br />
-Thank you once again for your continued help!
+CVM4_slice_??? : ??? is the layer number ( 001 is bottom and 100 is the surface of our initial model)<br />
+In each file, there are 8 columns.<br />
-David
+column1: grid number of X<br />
+column2: grid number of Y <br />
-On Thu, Jun 20, 2013 at 8:46 AM, 李(Lee) 恩瑞(En-Jui) <rickli92@yahoo.com.tw> wrote:
+column3: longitude<br />
-Hi Phil and David,
+column4: latitude<br />
+column5: elevation<br />
-I found the code for generating our initial model.
+column6: vp (m/s)<br />
+column7: vs (m/s)<br />
-(1) We give minima and corners of vp,vs and density.
+column8: density (kg/m^3)<br />
 == Interpolation Methods ==

← Older revision		Revision as of 16:47, 29 October 2013
Line 10:		Line 10:

	'''Please note''': While the perturbations span the entire CVM-S region horizontally, they are only 50km deep. As such, querying CVM-SI 20 below 50km will simply return CVM-S material properties.		'''Please note''': While the perturbations span the entire CVM-S region horizontally, they are only 50km deep. As such, querying CVM-SI 20 below 50km will simply return CVM-S material properties.
		+
		+	== Starting Model ==
		+
		+	So, let's see if we can go through each section:
		+
		+	Step 1:
		+
		+	2000. 3000. ! Minimum and corner of vp.
		+	1000. 1500. ! Minimum and corner of vs.
		+	2000. 2300. ! Minimum and corner of rho.(density)
		+
		+	read(,) modcvm(1),modcvm(2)
		+	read(,) modcvm(3),modcvm(4)
		+	read(,) modcvm(5),modcvm(6)
		+
		+	If I understand correctly, this means modcvm(1) contains the first value "2000", modcvm(2) contains "3000", modcvm(3) contains "1000", modcvm(4) = 1500, modcvm(5) = 2000, and modcvm(6) = 2300. Is this correct?
		+
		+	Step 2:
		+
		+	You would go through the extracted CVM-S mesh and locate the minimum Vp, Vs, and Rho values in the entire mesh.
		+
		+	Step 3:
		+
		+	Then you would apply a sequence of formulas:
		+
		+	if(alpha(ii).lt.modcvm(2)) alpha(ii)=(modcvm(2)(modcvm(1)-vpmin0)+alpha(ii)(modcvm(2)-modcvm(1)))/(modcvm(2)-vpmin0)
		+	if(beta(ii).lt.modcvm(4)) beta(ii)=(modcvm(4)(modcvm(3)-vsmin0)+beta(ii)(modcvm(4)-modcvm(3)))/(modcvm(4)-vsmin0)
		+	if(rho(ii).lt.modcvm(6)) rho(ii)=(modcvm(6)(modcvm(5)-dnmin0)+rho(ii)(modcvm(6)-modcvm(5)))/(modcvm(6)-dnmin0)
		+
		+	So to translate into pseudocode, these three equations would be:
		+
		+	If Vp < 3000 then Vp = (3000 * (2000 - Min_CVMS_Vp) + Vp * (3000 - 2000)) / (3000 - Min_CVMS_Vp)
		+	If Vs < 1500 then Vs = (1500 * (1000 - Min_CVMS_Vs) + Vs * (1500 - 1000)) / (1500 - Min_CVMS_Vs)
		+	If Rho < 2300 then Rho = (2300 * (2000 - Min_CVMS_Rho) + Rho * (2300 - 2000) / (2300 - Min_CVMS_Rho)
		+
		+	Finally, Step 4:
		+
		+	You would verify that if Vp/Vs was still less than 1.45 then we'd just set Vs = Vp / 1.45
		+
		+	Please let me know if this is an accurate "summarized" version of how this model was built. I'm just looking to double check that I have everything right.
		+
		+	Thank you once again for your continued help!
		+
		+	David
		+
		+	On Thu, Jun 20, 2013 at 8:46 AM, 李(Lee) 恩瑞(En-Jui) <rickli92@yahoo.com.tw> wrote:
		+	Hi Phil and David,
		+
		+	I found the code for generating our initial model.
		+
		+	(1) We give minima and corners of vp,vs and density.
		+
		+	2000. 3000. ! Minimum and corner of vp.
		+	1000. 1500. ! Minimum and corner of vs.
		+	2000. 2300. ! Minimum and corner of rho.(density)
		+
		+	read(,) modcvm(1),modcvm(2)
		+	read(,) modcvm(3),modcvm(4)
		+	read(,) modcvm(5),modcvm(6)
		+
		+
		+	(2) We find the minimum vp (vpmin0), vs(vsmin0), and density (dnmin0) in the original model.
		+
		+
		+	(3) We then modified the initial model based on the criteria:
		+
		+	if(alpha(ii).lt.modcvm(2)) alpha(ii)=(modcvm(2)(modcvm(1)-vpmin0)+alpha(ii)(modcvm(2)-modcvm(1)))/(modcvm(2)-vpmin0)
		+	if(beta(ii).lt.modcvm(4)) beta(ii)=(modcvm(4)(modcvm(3)-vsmin0)+beta(ii)(modcvm(4)-modcvm(3)))/(modcvm(4)-vsmin0)
		+	if(rho(ii).lt.modcvm(6)) rho(ii)=(modcvm(6)(modcvm(5)-dnmin0)+rho(ii)(modcvm(6)-modcvm(5)))/(modcvm(6)-dnmin0)
		+
		+	(4) We also check and fix the "negative lambda problem".
		+
		+	c fix negative lambda problem following Kim Olsen's suggestion
		+	if (alpha(ii)/beta(ii).lt.1.45) then
		+	beta(ii)=alpha(ii)/1.45
		+	endif
		+
		+	====================================================================================
		+
		+
		+	I have uploaded our initial model to "/auto/rcf-104/pochen/CVM4".
		+	The files are named by layer number.
		+	CVM4_slice_??? : ??? is the layer number ( 001 is bottom and 100 is the surface of our initial model)
		+	In each file, there are 8 columns.
		+	column1: grid number of X
		+	column2: grid number of Y
		+	column3: longitude
		+	column4: latitude
		+	column5: elevation
		+	column6: vp (m/s)
		+	column7: vs (m/s)
		+	column8: density (kg/m^3)

	== Interpolation Methods ==		== Interpolation Methods ==

@@ Line 19: / Line 19: @@
 '''Cosine Taper Where Vs < 1000m/s'''
-Plots using this method are available [here http://hypocenter.usc.edu/research/plots/cvms422]
+Plots using this method are available [http://hypocenter.usc.edu/research/plots/cvms422 here]
 Since the inversions were done with a Vs minimum of 1000m/s, one proposed method is to do a cosine taper in sections of the CVM-S model that have Vs < 1000m/s. More precisely, we define this method as:

← Older revision		Revision as of 05:13, 18 June 2013
Line 18:		Line 18:

	'''Cosine Taper Where Vs < 1000m/s'''		'''Cosine Taper Where Vs < 1000m/s'''
		+
		+	Plots using this method are available [here http://hypocenter.usc.edu/research/plots/cvms422]

	Since the inversions were done with a Vs minimum of 1000m/s, one proposed method is to do a cosine taper in sections of the CVM-S model that have Vs < 1000m/s. More precisely, we define this method as:		Since the inversions were done with a Vs minimum of 1000m/s, one proposed method is to do a cosine taper in sections of the CVM-S model that have Vs < 1000m/s. More precisely, we define this method as:

@@ Line 15: / Line 15: @@
 The broad idea behind CVM-SI21 is that we can take the low resolution perturbation mesh and interpolate it onto the CVM-S model, which is rule-based and therefore arbitrary precision. However, since the perturbations were calculated using a Vs minimum of 1000m/s, in certain areas of CVM-S (like boreholes), doing a straight trilinear interpolation of the perturbations with the CVM-S material properties can result in negative Vs and/or Vp values.
-In order to solve this problem, three interpolation methods have been defined:
+In order to solve this problem, three interpolation methods have been proposed:
 '''Cosine Taper Where Vs < 1000m/s'''

← Older revision		Revision as of 05:36, 6 June 2013
Line 33:		Line 33:

	Below are 5 plots that show the Vs 1D velocity profiles using this interpolation method.		Below are 5 plots that show the Vs 1D velocity profiles using this interpolation method.
		+
		+	*[http://northridge.usc.edu/cybershake/datarequest/plots/plot_USC.pdf USC cosine taper]
		+	*[http://northridge.usc.edu/cybershake/datarequest/plots/plot_DLA.pdf DLA cosine taper]
		+	*[http://northridge.usc.edu/cybershake/datarequest/plots/plot_PASC.pdf PASC cosine taper]
		+	*[http://northridge.usc.edu/cybershake/datarequest/plots/plot_SVD.pdf SVD cosine taper]
		+	*[http://northridge.usc.edu/cybershake/datarequest/plots/plot_Perris-2.pdf Perris-2 cosine taper]

	'''Linear Scaling Between Vs > 800m/s and Vs < 1200m/s in the GTL'''		'''Linear Scaling Between Vs > 800m/s and Vs < 1200m/s in the GTL'''