Case01b Reservoir Spatial_table

 

The present example is a variation of the base case in which all the data is identical except that the reservoir Material_data in file MEM_001_Case01b.mat has not poroelasticity data defined and instead reservoir Young modulus is defined to be a function of porosity via a Spatial_table.

 

The data files for the project are in: MEM_001\Case01\Data and the only files different from Case01 are:

•MEM_001_Case01b.dat

•MEM_001_Case01b.mat

 

 

Data File

 

* Spatial_table  NUM=1                    

! ---------------------------------                    

 Name               "Young"                    

 Variable_name                      

   "Young"                    

 Groups IDM=1                    

   "Reservoir"                    

 Dependent_variables IDM=1                    

   "Porosity"                    

 Dependent_grids  IDM=1                    

   "Internal"                          

 Update_frequency                      

   500                    

 Table_size       IDM=1                    

   6                    

 Table_values   IDM=2   JDM=6                    

   2400E6  0.15  

   2200E6  0.20

   2000E6  0.25

   1800E6  0.30

   1500E6  0.35

   1500E6  0.45

 

1.The Spatial_table data structure is used to define the Young's modulus for the group "Reservoir" as a function of the variable "Porosity".

 

2.The Dependent_grids is set to "Internal" as the model initial Porosity will be used to define the Young's modulus value.

 

3.Update_frequency is set to 500 so that Young's modulus value will be updated every 500 mechanical time steps if there is any porosity change.

 

4.Table_size is set to 6 as there is only one dependent variable (Porosity) and six values will be provided.

 

5.In Table_values the Young's modulus as a function of Porosity is defined. The values should be defined in an ascending porosity value order.

 

 

 

 

Results

 

The results for the project are located in MEM_001\Case01\Results. Complete results for the present case are not discussed here as the response of the model to the decrease in pore pressure is expected to be similar to Case01 provided that the only difference is the method of considering poroelasticity and the resulting distribution of Young's modulus values within the reservoir. Below it can be seen a comparison of the Young's modulus values after initialization obtained for both cases together with the respective dependent variables. It should be noted that poroelasticity in both cases could be set to obtain the same distribution in Young's modulus values.

 

MEM_001_Case01b_01

Young's modulus at the end of last initialization stage for Case01 and Case01b and their respective dependent variables.