GWF-CSUB

Structure of Blocks

FOR EACH SIMULATION

    BEGIN OPTIONS
      [BOUNDNAMES]
      [PRINT_INPUT]
      [SAVE_FLOWS]
      [GAMMAW <gammaw>]
      [BETA <beta>]
      [HEAD_BASED]
      [INITIAL_PRECONSOLIDATION_HEAD]
      [NDELAYCELLS <ndelaycells>]
      [COMPRESSION_INDICES]
      [UPDATE_MATERIAL_PROPERTIES]
      [CELL_FRACTION]
      [SPECIFIED_INITIAL_INTERBED_STATE]
      [SPECIFIED_INITIAL_PRECONSOLIDATION_STRESS]
      [SPECIFIED_INITIAL_DELAY_HEAD]
      [EFFECTIVE_STRESS_LAG]
      [STRAIN_CSV_INTERBED FILEOUT <interbedstrain_filename>]
      [STRAIN_CSV_COARSE FILEOUT <coarsestrain_filename>]
      [COMPACTION FILEOUT <compaction_filename>]
      [COMPACTION_ELASTIC FILEOUT <elastic_compaction_filename>]
      [COMPACTION_INELASTIC FILEOUT <inelastic_compaction_filename>]
      [COMPACTION_INTERBED FILEOUT <interbed_compaction_filename>]
      [COMPACTION_COARSE FILEOUT <coarse_compaction_filename>]
      [ZDISPLACEMENT FILEOUT <zdisplacement_filename>]
      [PACKAGE_CONVERGENCE FILEOUT <package_convergence_filename>]
      [TS6 FILEIN <ts6_filename>]
      [OBS6 FILEIN <obs6_filename>]
    END OPTIONS

    BEGIN DIMENSIONS
      NINTERBEDS <ninterbeds>
      [MAXSIG0 <maxsig0>]
    END DIMENSIONS

    BEGIN GRIDDATA
      CG_SKE_CR
            <cg_ske_cr(nodes)> -- READARRAY
      CG_THETA
            <cg_theta(nodes)> -- READARRAY
      [SGM
            <sgm(nodes)> -- READARRAY]
      [SGS
            <sgs(nodes)> -- READARRAY]
    END GRIDDATA

    BEGIN PACKAGEDATA
      <icsubno> <cellid(ncelldim)> <cdelay> <pcs0> <thick_frac> <rnb> <ssv_cc> <sse_cr> <theta> <kv> <h0> [<boundname>]
      <icsubno> <cellid(ncelldim)> <cdelay> <pcs0> <thick_frac> <rnb> <ssv_cc> <sse_cr> <theta> <kv> <h0> [<boundname>]
      ...
    END PACKAGEDATA

FOR ANY STRESS PERIOD

    BEGIN PERIOD <iper>
      <cellid(ncelldim)> <sig0>
      <cellid(ncelldim)> <sig0>
      ...
    END PERIOD

Explanation of Variables

Block: OPTIONS

  • BOUNDNAMES keyword to indicate that boundary names may be provided with the list of CSUB cells.

  • PRINT_INPUT keyword to indicate that the list of CSUB information will be written to the listing file immediately after it is read.

  • SAVE_FLOWS keyword to indicate that cell-by-cell flow terms will be written to the file specified with “BUDGET SAVE FILE” in Output Control.

  • gammaw unit weight of water. For freshwater, GAMMAW is 9806.65 Newtons/cubic meters or 62.48 lb/cubic foot in SI and English units, respectively. By default, GAMMAW is 9806.65 Newtons/cubic meters.

  • beta compressibility of water. Typical values of BETA are 4.6512e-10 1/Pa or 2.2270e-8 lb/square foot in SI and English units, respectively. By default, BETA is 4.6512e-10 1/Pa.

  • HEAD_BASED keyword to indicate the head-based formulation will be used to simulate coarse-grained aquifer materials and no-delay and delay interbeds. Specifying HEAD_BASED also specifies the INITIAL_PRECONSOLIDATION_HEAD option.

  • INITIAL_PRECONSOLIDATION_HEAD keyword to indicate that preconsolidation heads will be specified for no-delay and delay interbeds in the PACKAGEDATA block. If the SPECIFIED_INITIAL_INTERBED_STATE option is specified in the OPTIONS block, user-specified preconsolidation heads in the PACKAGEDATA block are absolute values. Otherwise, user-specified preconsolidation heads in the PACKAGEDATA block are relative to steady-state or initial heads.

  • ndelaycells number of nodes used to discretize delay interbeds. If not specified, then a default value of 19 is assigned.

  • COMPRESSION_INDICES keyword to indicate that the recompression (CR) and compression (CC) indices are specified instead of the elastic specific storage (SSE) and inelastic specific storage (SSV) coefficients. If not specified, then elastic specific storage (SSE) and inelastic specific storage (SSV) coefficients must be specified.

  • UPDATE_MATERIAL_PROPERTIES keyword to indicate that the thickness and void ratio of coarse-grained and interbed sediments (delay and no-delay) will vary during the simulation. If not specified, the thickness and void ratio of coarse-grained and interbed sediments will not vary during the simulation.

  • CELL_FRACTION keyword to indicate that the thickness of interbeds will be specified in terms of the fraction of cell thickness. If not specified, interbed thicknness must be specified.

  • SPECIFIED_INITIAL_INTERBED_STATE keyword to indicate that absolute preconsolidation stresses (heads) and delay bed heads will be specified for interbeds defined in the PACKAGEDATA block. The SPECIFIED_INITIAL_INTERBED_STATE option is equivalent to specifying the SPECIFIED_INITIAL_PRECONSOLITATION_STRESS and SPECIFIED_INITIAL_DELAY_HEAD. If SPECIFIED_INITIAL_INTERBED_STATE is not specified then preconsolidation stress (head) and delay bed head values specified in the PACKAGEDATA block are relative to simulated values of the first stress period if steady-state or initial stresses and GWF heads if the first stress period is transient.

  • SPECIFIED_INITIAL_PRECONSOLIDATION_STRESS keyword to indicate that absolute preconsolidation stresses (heads) will be specified for interbeds defined in the PACKAGEDATA block. If SPECIFIED_INITIAL_PRECONSOLITATION_STRESS and SPECIFIED_INITIAL_INTERBED_STATE are not specified then preconsolidation stress (head) values specified in the PACKAGEDATA block are relative to simulated values if the first stress period is steady-state or initial stresses (heads) if the first stress period is transient.

  • SPECIFIED_INITIAL_DELAY_HEAD keyword to indicate that absolute initial delay bed head will be specified for interbeds defined in the PACKAGEDATA block. If SPECIFIED_INITIAL_DELAY_HEAD and SPECIFIED_INITIAL_INTERBED_STATE are not specified then delay bed head values specified in the PACKAGEDATA block are relative to simulated values if the first stress period is steady-state or initial GWF heads if the first stress period is transient.

  • EFFECTIVE_STRESS_LAG keyword to indicate the effective stress from the previous time step will be used to calculate specific storage values. This option can 1) help with convergence in models with thin cells and water table elevations close to land surface; 2) is identical to the approach used in the SUBWT package for MODFLOW-2005; and 3) is only used if the effective-stress formulation is being used. By default, current effective stress values are used to calculate specific storage values.

  • STRAIN_CSV_INTERBED keyword to specify the record that corresponds to final interbed strain output.

  • FILEOUT keyword to specify that an output filename is expected next.

  • interbedstrain_filename name of the comma-separated-values output file to write final interbed strain information.

  • STRAIN_CSV_COARSE keyword to specify the record that corresponds to final coarse-grained material strain output.

  • coarsestrain_filename name of the comma-separated-values output file to write final coarse-grained material strain information.

  • COMPACTION keyword to specify that record corresponds to the compaction.

  • compaction_filename name of the binary output file to write compaction information.

  • COMPACTION_ELASTIC keyword to specify that record corresponds to the elastic interbed compaction binary file.

  • elastic_compaction_filename name of the binary output file to write elastic interbed compaction information.

  • COMPACTION_INELASTIC keyword to specify that record corresponds to the inelastic interbed compaction binary file.

  • inelastic_compaction_filename name of the binary output file to write inelastic interbed compaction information.

  • COMPACTION_INTERBED keyword to specify that record corresponds to the interbed compaction binary file.

  • interbed_compaction_filename name of the binary output file to write interbed compaction information.

  • COMPACTION_COARSE keyword to specify that record corresponds to the elastic coarse-grained material compaction binary file.

  • coarse_compaction_filename name of the binary output file to write elastic coarse-grained material compaction information.

  • ZDISPLACEMENT keyword to specify that record corresponds to the z-displacement binary file.

  • zdisplacement_filename name of the binary output file to write z-displacement information.

  • PACKAGE_CONVERGENCE keyword to specify that record corresponds to the package convergence comma spaced values file. Package convergence data is for delay interbeds. A warning message will be issued if package convergence data is requested but delay interbeds are not included in the package.

  • package_convergence_filename name of the comma spaced values output file to write package convergence information.

  • TS6 keyword to specify that record corresponds to a time-series file.

  • FILEIN keyword to specify that an input filename is expected next.

  • ts6_filename defines a time-series file defining time series that can be used to assign time-varying values. See the “Time-Variable Input” section for instructions on using the time-series capability.

  • OBS6 keyword to specify that record corresponds to an observations file.

  • obs6_filename name of input file to define observations for the CSUB package. See the “Observation utility” section for instructions for preparing observation input files. Tables ref{table:gwf-obstypetable} and ref{table:gwt-obstypetable} lists observation type(s) supported by the CSUB package.

Block: DIMENSIONS

  • ninterbeds is the number of CSUB interbed systems. More than 1 CSUB interbed systems can be assigned to a GWF cell; however, only 1 GWF cell can be assigned to a single CSUB interbed system.

  • maxsig0 is the maximum number of cells that can have a specified stress offset. More than 1 stress offset can be assigned to a GWF cell. By default, MAXSIG0 is 0.

Block: GRIDDATA

  • cg_ske_cr is the initial elastic coarse-grained material specific storage or recompression index. The recompression index is specified if COMPRESSION_INDICES is specified in the OPTIONS block. Specified or calculated elastic coarse-grained material specific storage values are not adjusted from initial values if HEAD_BASED is specified in the OPTIONS block.

  • cg_theta is the initial porosity of coarse-grained materials.

  • sgm is the specific gravity of moist or unsaturated sediments. If not specified, then a default value of 1.7 is assigned.

  • sgs is the specific gravity of saturated sediments. If not specified, then a default value of 2.0 is assigned.

Block: PACKAGEDATA

  • icsubno integer value that defines the CSUB interbed number associated with the specified PACKAGEDATA data on the line. CSUBNO must be greater than zero and less than or equal to NINTERBEDS. CSUB information must be specified for every CSUB cell or the program will terminate with an error. The program will also terminate with an error if information for a CSUB interbed number is specified more than once.

  • cellid is the cell identifier, and depends on the type of grid that is used for the simulation. For a structured grid that uses the DIS input file, CELLID is the layer, row, and column. For a grid that uses the DISV input file, CELLID is the layer and CELL2D number. If the model uses the unstructured discretization (DISU) input file, CELLID is the node number for the cell.

  • cdelay character string that defines the subsidence delay type for the interbed. Possible subsidence package CDELAY strings include: NODELAY–character keyword to indicate that delay will not be simulated in the interbed. DELAY–character keyword to indicate that delay will be simulated in the interbed.

  • pcs0 is the initial offset from the calculated initial effective stress or initial preconsolidation stress in the interbed, in units of height of a column of water. PCS0 is the initial preconsolidation stress if SPECIFIED_INITIAL_INTERBED_STATE or SPECIFIED_INITIAL_PRECONSOLIDATION_STRESS are specified in the OPTIONS block. If HEAD_BASED is specified in the OPTIONS block, PCS0 is the initial offset from the calculated initial head or initial preconsolidation head in the CSUB interbed and the initial preconsolidation stress is calculated from the calculated initial effective stress or calculated initial geostatic stress, respectively.

  • thick_frac is the interbed thickness or cell fraction of the interbed. Interbed thickness is specified as a fraction of the cell thickness if CELL_FRACTION is specified in the OPTIONS block.

  • rnb is the interbed material factor equivalent number of interbeds in the interbed system represented by the interbed. RNB must be greater than or equal to 1 if CDELAY is DELAY. Otherwise, RNB can be any value.

  • ssv_cc is the initial inelastic specific storage or compression index of the interbed. The compression index is specified if COMPRESSION_INDICES is specified in the OPTIONS block. Specified or calculated interbed inelastic specific storage values are not adjusted from initial values if HEAD_BASED is specified in the OPTIONS block.

  • sse_cr is the initial elastic coarse-grained material specific storage or recompression index of the interbed. The recompression index is specified if COMPRESSION_INDICES is specified in the OPTIONS block. Specified or calculated interbed elastic specific storage values are not adjusted from initial values if HEAD_BASED is specified in the OPTIONS block.

  • theta is the initial porosity of the interbed.

  • kv is the vertical hydraulic conductivity of the delay interbed. KV must be greater than 0 if CDELAY is DELAY. Otherwise, KV can be any value.

  • h0 is the initial offset from the head in cell cellid or the initial head in the delay interbed. H0 is the initial head in the delay bed if SPECIFIED_INITIAL_INTERBED_STATE or SPECIFIED_INITIAL_DELAY_HEAD are specified in the OPTIONS block. H0 can be any value if CDELAY is NODELAY.

  • boundname name of the CSUB cell. BOUNDNAME is an ASCII character variable that can contain as many as 40 characters. If BOUNDNAME contains spaces in it, then the entire name must be enclosed within single quotes.

Block: PERIOD

  • iper integer value specifying the starting stress period number for which the data specified in the PERIOD block apply. IPER must be less than or equal to NPER in the TDIS Package and greater than zero. The IPER value assigned to a stress period block must be greater than the IPER value assigned for the previous PERIOD block. The information specified in the PERIOD block will continue to apply for all subsequent stress periods, unless the program encounters another PERIOD block.

  • cellid is the cell identifier, and depends on the type of grid that is used for the simulation. For a structured grid that uses the DIS input file, CELLID is the layer, row, and column. For a grid that uses the DISV input file, CELLID is the layer and CELL2D number. If the model uses the unstructured discretization (DISU) input file, CELLID is the node number for the cell.

  • sig0 is the stress offset for the cell. SIG0 is added to the calculated geostatic stress for the cell. SIG0 is specified only if MAXSIG0 is specified to be greater than 0 in the DIMENSIONS block. If the Options block includes a TIMESERIESFILE entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.

Example Input File

    BEGIN OPTIONS
      COMPRESSION_INDICES
      SPECIFIED_INITIAL_INTERBED_STATE
      BOUNDNAMES
      SAVE_FLOWS
    END OPTIONS
    
    BEGIN DIMENSIONS
      NINTERBEDS  4
      MAXSIG0  1
    END DIMENSIONS
    
    BEGIN GRIDDATA
      # compression indices of coarse grained aquifer materials
      cg_ske_cr LAYERED
        CONSTANT       0.01
        CONSTANT       0.01
        CONSTANT       0.01
        CONSTANT       0.01
      # porosity of coarse grained aquifer materials
      cg_theta LAYERED
        CONSTANT       0.45
        CONSTANT       0.45
        CONSTANT       0.45
        CONSTANT       0.45
      # specific gravity of saturated sediment
      SGS LAYERED
          CONSTANT 2.0
          CONSTANT 2.0
          CONSTANT 2.0
          CONSTANT 2.0
      # specific gravity of moist sediment
      SGM LAYERED
          CONSTANT 1.7
          CONSTANT 1.7
          CONSTANT 1.7
          CONSTANT 1.7
    END GRIDDATA
    
    BEGIN PACKAGEDATA
    # icsubsno cellid cdelay     pcs0  thick_frac rnb ssv_cc sse_cr theta     kv  h0 boundname
              1 1 1 6   delay    15.0       0.450 1.0   0.25    0.01    0.45 0.1 15. nsystm0
              2 1 1 7   nodelay 15.0        0.450 1.0   0.25    0.01    0.45 0.0 0.0 nsystm1
              3 1 1 8   nodelay 15.0        0.450 1.0   0.25    0.01    0.45 0.0 0.0 nsystm1
              4 1 1 9   delay    15.0       0.450 1.0   0.25    0.01    0.45 0.1 15. nsystm2
    END PACKAGEDATA
    
    BEGIN PERIOD 1
    # stress offset for stress period 1
      1 1 6    1700.00000000
    END PERIOD

Available Observation Types

Stress Package Observation Type ID1 ID2 Description
CSUB csub icsubno or boundname -- Flow between the groundwater system and a interbed or group of interbeds.
CSUB inelastic-csub icsubno or boundname -- Flow between the groundwater system and a interbed or group of interbeds from inelastic compaction.
CSUB elastic-csub icsubno or boundname -- Flow between the groundwater system and a interbed or group of interbeds from elastic compaction.
CSUB coarse-csub cellid -- Flow between the groundwater system and coarse-grained materials in a GWF cell.
CSUB csub-cell cellid -- Flow between the groundwater system for all interbeds and coarse-grained materials in a GWF cell.
CSUB wcomp-csub-cell cellid -- Flow between the groundwater system for all interbeds and coarse-grained materials in a GWF cell from water compressibility.
CSUB sk icsubno or boundname -- Convertible interbed storativity in a interbed or group of interbeds. Convertible interbed storativity is inelastic interbed storativity if the current effective stress is greater than the preconsolidation stress. The NODATA value is reported for steady-state stress periods.
CSUB ske icsubno or boundname -- Elastic interbed storativity in a interbed or group of interbeds. The NODATA value is reported for steady-state stress periods.
CSUB sk-cell cellid -- Convertible interbed and coarse-grained material storativity in a GWF cell. Convertible interbed storativity is inelastic interbed storativity if the current effective stress is greater than the preconsolidation stress. The NODATA value is reported for steady-state stress periods.
CSUB ske-cell cellid -- Elastic interbed and coarse-grained material storativity in a GWF cell. The NODATA value is reported for steady-state stress periods.
CSUB estress-cell cellid -- effective stress in a GWF cell.
CSUB gstress-cell cellid -- geostatic stress in a GWF cell.
CSUB interbed-compaction icsubno or boundname -- interbed compaction in a interbed or group of interbeds.
CSUB inelastic-compaction icsubno or boundname -- inelastic interbed compaction in a interbed or group of interbeds.
CSUB elastic-compaction icsubno or boundname -- elastic interbed compaction a interbed or group of interbeds.
CSUB coarse-compaction cellid -- elastic compaction in coarse-grained materials in a GWF cell.
CSUB inelastic-compaction-cell cellid -- inelastic compaction in all interbeds in a GWF cell.
CSUB elastic-compaction-cell cellid -- elastic compaction in coarse-grained materials and all interbeds in a GWF cell.
CSUB compaction-cell cellid -- total compaction in coarse-grained materials and all interbeds in a GWF cell.
CSUB thickness icsubno or boundname -- thickness of a interbed or group of interbeds.
CSUB coarse-thickness cellid -- thickness of coarse-grained materials in a GWF cell.
CSUB thickness-cell cellid -- total thickness of coarse-grained materials and all interbeds in a GWF cell.
CSUB theta icsubno -- porosity of a interbed .
CSUB coarse-theta cellid -- porosity of coarse-grained materials in a GWF cell.
CSUB theta-cell cellid -- thickness-weighted porosity of coarse-grained materials and all interbeds in a GWF cell.
CSUB delay-flowtop icsubno -- Flow between the groundwater system and a delay interbed across the top of the interbed.
CSUB delay-flowbot icsubno -- Flow between the groundwater system and a delay interbed across the bottom of the interbed.
CSUB delay-head icsubno idcellno head in interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS). The NODATA value is reported for steady-state stress periods.
CSUB delay-gstress icsubno idcellno geostatic stress in interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS). The NODATA value is reported for steady-state stress periods.
CSUB delay-estress icsubno idcellno effective stress in interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS). The NODATA value is reported for steady-state stress periods.
CSUB delay-preconstress icsubno idcellno preconsolidation stress in interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS). The NODATA value is reported for steady-state stress periods.
CSUB delay-compaction icsubno idcellno compaction in interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS).
CSUB delay-thickness icsubno idcellno thickness of interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS).
CSUB delay-theta icsubno idcellno porosity of interbed delay cell idcellno (1 <= idcellno <= NDELAYCELLS).
CSUB preconstress-cell cellid -- preconsolidation stress in a GWF cell containing at least one interbed. The NODATA value is reported for steady-state stress periods.

Example Observation Input File

    BEGIN CONTINUOUS FILEOUT  my_model.csub.csv
      tcomp3        compaction-cell        1 1 7
      ibcensystm0   elastic-compaction     nsystm0
      ibcinsystm0   inelastic-compaction   nsystm0
    END CONTINUOUS