[cig-commits] r16879 - seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN

[carltape at geodynamics.org]

Author: carltape
Date: 2010-06-03 07:41:26 -0700 (Thu, 03 Jun 2010)
New Revision: 16879

Modified:
   seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/compute_rho_estimate.f90
   seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/constants.h.in
Log:
Modified Vp-rho scaling to use that of Brocher et al. (2005).


Modified: seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/compute_rho_estimate.f90
===================================================================
--- seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/compute_rho_estimate.f90	2010-06-03 14:12:04 UTC (rev 16878)
+++ seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/compute_rho_estimate.f90	2010-06-03 14:41:26 UTC (rev 16879)
@@ -25,18 +25,33 @@
 
   subroutine compute_rho_estimate(rho,vp)
 
-! compute rho estimate in Gocad block and in Hauksson's model
-! based upon Vp
+! compute rho estimate in Gocad block and in Hauksson model from Vp
 
   implicit none
 
   include "constants.h"
 
   double precision rho,vp
+  double precision :: P0, P1, P2, P3, P4, P5
 
-! scale density - use empirical rule from Christiane
-  rho = 0.33d0 * vp + 1280.d0
+!!$! Vp-rho empirical rule from Stidham et al. (2001)
+!!$! -- used in Komatitsch et al. (2004) simulations
+!!$  P1 = 0.33d0 
+!!$  P0 = 1280.d0
+!!$  rho = P1*vp + P0
+!!$!  rho = 0.33d0 * vp + 1280.d0
 
+! Vp-rho empirical rule from Ludwig-Nafe-Drake (1970),
+! which is listed in Brocher (2005a)
+! -- used in Tape et al. (2009) simulations
+   P5 =  1.0600d-16
+   P4 = -4.3000d-12
+   P3 =  6.7100d-08
+   P2 = -4.7210d-04
+   P1 =  1.6612d0
+   P0 =  0.0d0
+   rho = P5*vp**5 + P4*vp**4 + P3*vp**3 + P2*vp**2 + P1*vp + P0
+
 ! make sure density estimate is reasonable
   if(rho > DENSITY_MAX) rho = DENSITY_MAX
   if(rho < DENSITY_MIN) rho = DENSITY_MIN

Modified: seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/constants.h.in
===================================================================
--- seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/constants.h.in	2010-06-03 14:12:04 UTC (rev 16878)
+++ seismo/3D/SPECFEM3D_SESAME/tags/v1.4.4_last_BASIN/constants.h.in	2010-06-03 14:41:26 UTC (rev 16879)
@@ -74,9 +74,9 @@
 ! to avoid taking into account spurious oscillations in topography model
   double precision, parameter :: MINIMUM_THICKNESS_3D_OCEANS = 10.d0
 
-! min and max density in the model
-  double precision, parameter :: DENSITY_MAX = 3000.d0
-  double precision, parameter :: DENSITY_MIN = 2000.d0
+! min and max density in the model (based on Brocher, 2005, eq. 1)
+  double precision, parameter :: DENSITY_MAX = 3476.d0  ! 3000.d0
+  double precision, parameter :: DENSITY_MIN = 1635.d0  ! 2000.d0
 
 ! density of sea water
   real(kind=CUSTOM_REAL), parameter :: RHO_OCEANS = 1020.0