Index: /issm/trunk-jpl/src/c/classes/objects/Elements/Tria.cpp
===================================================================
--- /issm/trunk-jpl/src/c/classes/objects/Elements/Tria.cpp	(revision 14899)
+++ /issm/trunk-jpl/src/c/classes/objects/Elements/Tria.cpp	(revision 14900)
@@ -3097,6 +3097,7 @@
 	IssmDouble lithosphere_density;
 	IssmDouble mantle_shear_modulus;
+	IssmDouble mantle_density;
+	Input* mantle_viscosity_input=NULL;
 	IssmDouble mantle_viscosity;
-	IssmDouble mantle_density;
 	Input* lithosphere_thickness_input=NULL;
 	IssmDouble lithosphere_thickness;
@@ -3130,5 +3131,4 @@
 	lithosphere_density=matpar->GetLithosphereDensity();
 	mantle_shear_modulus=matpar->GetMantleShearModulus();
-	mantle_viscosity=matpar->GetMantleViscosity();
 	mantle_density=matpar->GetMantleDensity();
 	rho_ice=matpar->GetRhoIce();
@@ -3138,4 +3138,9 @@
 	if (!thickness_input)_error_("thickness input needed to compute gia deflection!");
 	thickness_input->GetInputUpToCurrentTimeAverages(&hes,&times,&numtimes,currenttime);
+
+	/*recover mantle viscosity: */
+	mantle_viscosity_input=inputs->GetInput(GiaMantleViscosityEnum);
+	if (!mantle_viscosity_input)_error_("mantle viscosity input needed to compute gia deflection!");
+	mantle_viscosity_input->GetInputAverage(&mantle_viscosity);
 
 	/*recover lithosphere thickness: */
Index: /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.cpp
===================================================================
--- /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.cpp	(revision 14899)
+++ /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.cpp	(revision 14900)
@@ -81,5 +81,4 @@
 	iomodel->Constant(&this->lithosphere_density,MaterialsLithosphereDensityEnum);
 	iomodel->Constant(&this->mantle_shear_modulus,MaterialsMantleShearModulusEnum);
-	iomodel->Constant(&this->mantle_viscosity,MaterialsMantleViscosityEnum);
 	iomodel->Constant(&this->mantle_density,MaterialsMantleDensityEnum);
 
@@ -458,9 +457,4 @@
 }		 
 /*}}}*/ 
-/*FUNCTION Matpar::GetMantleViscosity {{{*/			 
-IssmDouble Matpar::GetMantleViscosity(){		 
-	return mantle_viscosity;			 
-}		 
-/*}}}*/ 
 /*FUNCTION Matpar::UnitConversion {{{*/			 
 void Matpar::UnitConversion(void){		 
Index: /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.h
===================================================================
--- /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.h	(revision 14899)
+++ /issm/trunk-jpl/src/c/classes/objects/Materials/Matpar.h	(revision 14900)
@@ -55,5 +55,4 @@
 		IssmDouble lithosphere_density;
 		IssmDouble mantle_shear_modulus;
-		IssmDouble mantle_viscosity;
 		IssmDouble mantle_density;
 
@@ -131,5 +130,4 @@
 		IssmDouble GetLithosphereDensity();
 		IssmDouble GetMantleShearModulus();
-		IssmDouble GetMantleViscosity();
 		IssmDouble GetMantleDensity();
 		void   EnthalpyToThermal(IssmDouble* ptemperature,IssmDouble* pwaterfraction,IssmDouble enthalpy,IssmDouble pressure);