User:Jcreer/MDOFLOW 6 New Packages

MF6 BUY Package

The Buoyancy (BUY) Package dialog

The Buoyancy (BUY) Package dialog is accessed by double-clicking on the BUY package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- Comments – Turn on to make the Comments section visible.
- Options – Turn on to make the Options section visible.
- PACKAGEDATA – Turn on to make the PACAKGEDATA section visible. This section is on by default.
Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
Options section – Temporal options and settings:
- HHFORMULATION_RHS – Using variable-density hydraulic head formulation on the right-hand, this prevents adding asymmetric terms to the flow matrix.
- DENSEREF – This allows a fluid reference density to be specified in the equation of state. If not active to be specified, this value is set to 1000.
- DENSITY FILEOUT – This allows the density to be saved to a binary output file that is specified.
PACKAGEDATA section – This deals with the PACKAGEDATA block. It is a spreadsheet section which contains the following:
- Add Rows... – This button brings up a Rows to Add dialog, where a number can be specified to the right of Number of rows to add at bottom. This will help populate the spreadsheet.
- IRHOSPEC – This column represents the IRHOSPEC integer values, which define the species numbers for the PACKAGEDATA on each line. These must be greater than zero and less than or equal to the separately defined NRHOSPECIES value. The program will terminate with an error if an NRHOSPECIES species doesn't have information specified, or if its information is specified more than once.
- DRHODC – This column represents the DRHODC values, which define the slopes of the density-concentration lines used in the density equation of state.
- CRHOREF – This column represents the CRHOREF values, which define the reference concentration values used in the density equation of state.
- MODELNAME – This column represents the MODELNAME values, which names the GWT models that will be used to simulate species in the density equation of state. This will only work if the simulation includes a GWT model that corresponds to the name.
- AUXSPECIESNAME – This column represents the AUXSPECIESNAME values, which names GWF stress package auxiliary variables that will be used to calculate a density value. The Buoyancy Package can use these simulated concentration values to calculate density values for lakes, streams, multi-aquifer wells, and unsaturated zone flow cells.

MF6 CSUB Package

The Skeletal Storage, Compaction, and Subsidence (CSUB) Package dialog

The Skeletal Storage, Compaction, and Subsidence (CSUB) Package dialog is accessed by double-clicking on the CSUB package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
- DATA – Turn on to make the DATA section visible. This section is on by default.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- BOUNDNAMES – This allows for boundary names to be provided with the list of CSUB cells.
- PRINT_INPUT – This indicates that the list of CSUB input will be printed to the listing file immediately after it is read.
- SAVE_FLOWS – This indicates that cell-by-cell flow terms will be saved to a budget file (specified in Output Control with "BUDGET SAVE FILE").
- GAMMAW – This allows the unit weight of water to be set. For freshwater, GAMMAW is 9806.65 Newtons/cubic meters (SI) or 62.48 lb/cubic foot (English units). The default value for GAMMAW is 9806.65 Newtons/cubic meters.
- BETA – This allows for the compressibility of water to be set. Typical values of BETA are 4.6512e-10 1/Pa (SI) or 2.2270e-8 lb/square foot (English units). The default value for BETA is 4.6512e-10 1/Pa.
- HEAD_BASED – This indicates that head-based formulation will be used to simulate coarse-grained aquifer materials and no-delay and delay interbeds. If specified, then INITIAL_PRECONSOLIDATION_HEAD will be as well.
- INITIAL_PRECONSOLIDATION_HEAD – This indicates that preconsolidation heads will be specified for no-delay and delay interbeds in the PACKAGEDATA block. When SPECIFIED_INTIAL_INTERBED_STATE is specified, these will be absolute values. When it isn't, these will be relative to steady-state or initial heads.
- NDELAYCELLS – This allows a number to be set for the number of nodes used to discretize delay interbeds. When this isn't set, a default value of 19 is assigned.
- COMPRESSION_INDICES – This indicates that recompression (CR) and compression (CC) indices will be specified, replacing the elastic specific storage (SSE) and inelastic specific storage (SSV) coefficients. When this isn't set, the SSE and SSV coefficients will have to be specified.
- UPDATE_MATERIAL_PROPERTIES – This indicates that the thickness and void ratio of coarse-grained and interbed sediments (delay and no-delay) will vary during the simulation. When this isn't set, the ratio will not vary during the simulation.
- CELL_FRACTION – This indicates that interbed thickness will be specified as a fraction of cell thickness. When this isn't set, the interbed thickness will have to be individually specified.
- SPECIFIED_INITIAL_INTERBED_STATE – This indicates that absolute preconsolidation stresses (heads) and delay bed heads will be specified for the interbeds that are defined in the PACKAGEDATA block. This is equivalent to specifying both SPECIFIED_INITIAL_PRECONSOLDIATION_STRESS and SPECIFIED_INITIAL_DELAY_HEAD. If this option is not set, then these values will be relative to simulated values (if the first stress period is steady-state) or initial stresses and GWF heads (if the first stress period is transient).
- SPECIFIED_INITIAL_PRECONSOLIDATION_STRESS – This indicates that absolute preconsolidation stresses (heads) will be specified for interbeds that are defined in the PACKAGEDATA block. If neither this option nor SPECIFIED_INITIAL_INTERBED_STATE are set, then these values will be 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 – This indicates that absolute initial delay bed head will be specified for interbeds that are defined in the PACKAGEDATA block. If neither this option nor SPECIFIED_INITIAL_INTERBED_STATE are set, then these values will be 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 – This indicates that effective stress from the previous time step will be used to calculate specific storage values. This is helpful with convergence in models with thin cells and water table elevations close to land surface, is identical to the SUBWT package approach for MODFLOW-2005, and will only be used when the effective-stress formulation is being used. When this isn't set, the default is to use current effective stress values to calculate specific storage values.
- STRAIN_CSV_INTERBED – This allows the final interbed strain output to be saved to a specified file.
- STRAIN_CSV_COARSE – This allows the final coarse-grained material strain output to be saved to a specified file.
- COMPACTION – This allows the compaction to be saved to a specified file.
- COMPACTION_ELASTIC – This allows the elastic interbed compaction to be saved to a specified binary file.
- COMPACTION_INELASTIC – This allows the inelastic interbed compaction to be saved to a specified binary file.
- COMPACTION_INTERBED – This allows the interbed compaction to be saved to a specified binary file.
- COMPACTION_COARSE – This allows the elastic coarse-grained material compaction to be saved to a specified binary file.
- ZDISPLACEMENT – This allows the z-displacement to be saved to a specified binary file.
- PACKAGE_CONVERGENCE – This allows the package convergence info to be saved to a comma-separated values (CSV) file.
- TS6 FILEIN – This allows time-series files to be used as input to assign time-varying values. Specifying this option will allow a Files... button to its right to be clicked. Doing so will bring up a Files dialog. In this dialog, a spreadsheet can be filled in that has two columns. The following options can be used to help develop the spreadsheet:
  - Insert Row – This will insert a new row at the current location.
  - Add Row – This will add a new row at the bottom.
  - Delete Row – This will delete the currently selected row.
  - Move Up – This will move the currently selected row up a row.
  - Move Down – This will move the currently selected row down a row.
- OBS6 FILEIN – This allows observations files to be used as input. Specifying this option will allow a Files... button to its right to be clicked. Doing so will bring up a Files dialog. In this dialog, a spreadsheet can be filled in that has two columns. The first column allows filenames to be specified. The second column has an Edit... button relating to the file specified. The following options can be used to help develop the spreadsheet:
  - Insert Row – This will insert a new row at the current location.
  - Add Row – This will add a new row at the bottom.
  - Delete Row – This will delete the currently selected row.
  - Move Up – This will move the currently selected row up a row.
  - Move Down – This will move the currently selected row down a row.
GRIDDATA section – This deals with the GRIDDATA block.
- Dataset to Array... – This button brings up a Select Dataset dialog, where a single dataset can be selected for use in the GRIDDATA section. This will populate its spreadsheet. This option is grayed out if Define is not turned on. The CG_SKE_CR and CG_THETA tabs do not have the Define option visible, so the button is always available for them.
- Define – This allows data within the GRIDDATA section to be defined. When this is inactive, all of the options within a given tab are grayed out. This option is unavailable in the CG_SKE_CR and CG_THETA tabs, so they are automatically defined.
- Layered – When this is active, a numeric updown for the layers will become available.
- Drop-down and Constant/Factor – The drop-down in the GRIDDATA section has two options. The option selected will change the nature of the textbox to its right.
  - CONSTANT – This will change the textbox to the right to be representative of "Constant". If this is selected, the spreadsheet in the GRIDDATA section will be grayed out.
  - ARRAY – This will change the textbox to the right to be representative of "Factor". If this is selected, the spreadsheet in the GRIDDATA section will not be grayed out, and its cells will be editable.
- CG_SKE_CR – The CG_SKE_CR tab represents either the initial elastic coarse-grained material specific storage of recompression index. If COMPRESSION_INDICES was set, then this will represent the recompression index. Otherwise this will represent the elastic specific storage. If HEAD_BASED was set, then specified/calculated elastic coarse-grained material specific storage values will not be adjusted from the initial values.
- CG_THETA – The CG_THETA tab represents the initial porosity of coarse-grained materials.
- SGM – The SGM tab represents the specific gravity of moist or unsaturated sediments. When this isn't specified, a default value of 1.7 will be used.
- SGS – The SGS tab represents the specific gravity of saturated sediments. When this isn't specified, a default value of 2.0 will be used.
DATA section – Contains the following tabs:
- PACKAGEDATA – This deals with the PACKAGEDATA block.
  - Add Rows... – This button brings up a Rows to Add dialog, where a number can be specified to the right of Number of rows to add at bottom. This will help populate the spreadsheet.
  - Filter on Selected Cells – ???
  - ICSUBNO – This column represents the ICSUBNO integer values, which define the CSUB interbed numbers for the PACKAGEDATA on each line. The CSUBNO values must be greater than zero and less than or equal to the separately defined NINTERBEDS value. The program will terminate with an error if a CSUB cell doesn't have information specified, or if information for a CSUB interbed number is specified more than once.
  - CELLID – This will display differently in the spreadsheet based on what type of grid is used for the simulation, specifically which type of DIS* input file is used in the model. The CELLID is the cell identifier, and the type of DIS* file used will change what will be determined to be the CELLID.
    - For a structured grid that uses a DIS input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - ROW – This column represents the rows of the cells.
      - COL – This column represents the columns of the cells.
    - For a grid that uses a DISV input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - CELL2D – This column represents the CELL2D numbers of the cells.
    - If the model uses a DISU (unstructured discretization) file, the column will be:
      - CELLID – This column represents the node numbers of the cells.
  - CDELAY – This column represents the CDELAY character strings, which define the subsidence package delay type for the interbeds. Possible CDELAY strings include:
    - NODELAY – Character keyword that indicates delay will not be simulated in the interbed.
    - DELAY – Character keyword that indicates delay will be simulated in the interbed.
  - PCS0 – This column represents the PCS0 values, which are the initial offsets from the calculated initial effective/preconsolidation stress in the interbeds, in the units of the height of a column of water. If SPECIFIED_INITIAL_INTERBED_STATE or SPECIFIED_INITIAL_PRECONSOLIDATION_STRESS are set, then these are the initial preconsolidation stresses. If HEAD_BASED is set, then these are the initial offsets from the calculated initial head/preconsolidation heads in the CSUB interbeds, and initial preconsolidation stresses are calculated from the calculated initial effective/geostatic stresses.
  - THICK_FRAC – This column represents the THICK_FRAC values, which are the interbed thickness/cell fractions of the interbeds. If CELL_FRACTION is set, interbed thickness is specified as a fraction of the cell thickness.
  - RNB – This column represents the RNB values, which are the interbed material factor equivalent numbers of interbeds in the interbed systems represented by the interbeds. If CDELAY has been set to DELAY, these values must be greater than or equal to 1. If not, then these values can be any value.
  - SSV_CC – This column represents the SSV_CC values, which are the initial inelastic specific storages or compression indexes of the interbeds. If COMPRESSION_INDICES is set, then the compression index is specified. If HEAD_BASED is set, then specified/calculated interbed inelastic specific storage values are not adjusted from the initial values.
  - SSE_CR – This column represents the SSE_CR values, which are the initial elastic coarse-grained material specific storages or recompression indexes of the interbeds. If COMPRESSION_INDICES is set, then the recompression index is specified. If HEAD_BASED is set, then the specified/calculated interbed elastic specific storage values are not adjusted from the initial values.
  - THETA – This column represents the THETA values, which are the initial porosities of the interbeds.
  - KV – This column represents the KV values, which are the vertical hydraulic conductivities of the delay interbeds. If CDELAY has been set to DELAY, these must be greater than 0. If not, then these values can be any value.
  - H0 – This column represents the H0 values, which are the initial offsets from the heads in cell CELLIDs or the initial heads in the delay interbeds. If SPECIFIED_INITIAL_INTERBED_STATE or SPECIFIED_INITIAL_DELAY_HEAD are set, then these are the initial heads in the delay beds. If CDELAY has been set to NODELAY, then these can be any value.
- PERIODS – This deals with the PERIODS block.
  - Period – A numeric updown can be used to enter which period is being examined in the spreadsheet.
  - Define Period – This button will allow a period to be defined. This will be active when no period has yet been defined, and it may gray out once one has been created.
  - Delete Period – This button will delete the selected period. A dialog warning will come up first asking the user to confirm their decision to delete the period.
  - Add Rows – This button will bring up an Add Stresses dialog. The following options can be used to help in adding the stresses:
    - Columns and Values – Numeric updowns and textboxes can be used to enter the values for their relevant columns for all the new stresses. These may include columns that are not actually present in the spreadsheet.
    - Number of rows to add – A numeric updown can be used to enter the number of rows that will be added to the spreadsheet.
    - Add to – There are two different options, only one of which can be selected at a time.
      - All defined periods – These stresses will be added to all the periods that have been defined.
      - Only this period – These stresses will be added only to the currently selected period.
  - Delete Rows – This button will delete all of the stresses. A dialog warning will come up first asking the user to confirm their decision to delete the stresses. The dialog will also give them the option to either Delete From All Periods or Delete From Just This Period.
  - Plot All Periods – This will allow the user to plot all the periods that have been defined.
  - Open Time Series – This will allow the user to open a time-series file.
  - The columns listed in the spreadsheet will differ, based on which type of DIS* input file is used in the model.
    - If the model uses a DIS input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - ROW – This column represents the rows of the cells.
      - COL – This column represents the columns of the cells.
      - SIG0 – This column represents the stress offsets for the cells. SIG0 is added to the calculated geostatic stresses for the cells. SIG0 will only be specified if a separately defined MAXSIG0 value is set to be greater than 0. If time-series files are used as input, entering a time-series name instead of a numeric value can allow for values to be obtained from a time series.
    - If the model uses a DISV input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - ROW – This column represents the rows of the cells.
      - COL – This column represents the columns of the cells.
    - If the model uses a DISU input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - ROW – This column represents the rows of the cells.

MF6 ADV Package

The Advection (ADV) Package dialog

The Advection (ADV) Package dialog is accessed by double-clicking on the ADV package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- SCHEME – This drop-down can be used to select which weighting scheme will be used to solve the advection term. There are three options:
  - upstream – An upstream weighting scheme will be used. This is the default option.
  - central – A central weighting scheme will be used.
  - TVD – A TVD weighting scheme will be used.

MF6 CNC Package

The Constant Concentration (CNC) Package dialog

The Constant Concentration (CNC) Package dialog is accessed by double-clicking on the CNC package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- PERIODS – Turn on to make the PERIODS section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- AUXILIARY – This allows an array of one or more auxiliary variables to be named. There are no limits to the number of auxiliary variables that can be provided, but subsequent blocks will require data for each of the auxiliary variables that are defined. Turning this on will activate an Auxiliary Variables... button. Clicking the button will bring up an Auxiliary Variables dialog. The following options can be used to help develop the auxiliary variables:
  - Insert Row – This will insert a new row at the current location.
  - Add Row – This will add a new row at the bottom.
  - Delete Row – This will delete the currently selected row.
  - Move Up – This will move the currently selected row up a row.
  - Move Down – This will move the currently selected row down a row.
- AUXMULTNAME – This allows for an auxiliary variable to be used as a multiplier of concentration value. A textbox to the right of the option can be used to specify the name.
- BOUNDNAMES – This indicates that boundary names are allowed to be provided with the list of constant concentration cells.
- PRINT_INPUT – This indicates that the list of constant concentration information will be printed to the listing file immediately after it is read.
- PRINT_FLOWS – This indicates that the list of constant concentration flow rates will be printed to the listing file. Flow rates will be printed for the last time step of each stress period.
- SAVE_FLOWS – This indicates that constant concentration flow terms will be saved to a budget file (specified in Output Control with "BUDGET FILEOUT").
- TS6 FILEIN – This allows time-series files to be used as input to assign time-varying values. Specifying this option will allow a Files... button to its right to be clicked. Doing so will bring up a Files... dialog. In this dialog, a spreadsheet can be filled in that has two columns. The following options can be used to help develop the spreadsheet:
  - Insert Row – This will insert a new row at the current location.
  - Add Row – This will add a new row at the bottom.
  - Delete Row – This will delete the currently selected row.
  - Move Up – This will move the currently selected row up a row.
  - Move Down – This will move the currently selected row down a row.
- OBS6 FILEIN – This allows observations files to be used as input. Specifying this option will allow a Files... button to its right to be clicked. Doing so will bring up an Observation Files dialog. In this dialog, a spreadsheet can be filled in that has two columns. The first column allows filenames to be specified. The second column has an Edit... button relating to the file specified. The following options can be used to help develop the spreadsheet:
  - Insert Row – This will insert a new row at the current location.
  - Add Row – This will add a new row at the bottom.
  - Delete Row – This will delete the currently selected row.
  - Move Up – This will move the currently selected row up a row.
  - Move Down – This will move the currently selected row down a row.
PERIODS section – This deals with the PERIODS block.
- Period – A numeric updown can be used to enter which period is being examined in the spreadsheet.
- Define Period – This button will allow a period to be defined. This will be active when no period has yet been defined, and it may gray out once one has been created.
- Delete Period – This button will delete the selected period. A dialog warning will come up first asking the user to confirm their decision to delete the period.
- Add Rows – This button will bring up an Add Stresses dialog. The following options can be used to help in adding the stresses:
  - - Columns and Values – Numeric updowns and textboxes can be used to enter the values for their relevant columns for all the new stresses. These may include columns that are not actually present in the spreadsheet.
    - Number of rows to add – A numeric updown can be used to enter the number of rows that will be added to the spreadsheet.
    - Add to – There are two different options, only one of which can be selected at a time.
      - All defined periods – These stresses will be added to all the periods that have been defined.
      - Only this period – These stresses will be added only to the currently selected period.
- Delete Rows – This button will delete all of the stresses. A dialog warning will come up first asking the user to confirm their decision to delete the stresses. The dialog will also give them the option to either Delete From All Periods or Delete From Just This Period.
- Plot All Periods – This will allow the user to plot all the periods that have been defined.
- Open Time Series – This will allow the user to open a time-series file.
- Filter on Selected Cells – ???
- CELLID – This will display differently in the spreadsheet based on what type of grid is used for the simulation, specifically which type of DIS* input file is used in the model. The CELLID is the cell identifier, and the type of DIS* file used will change what will be determined to be the CELLID.
  - - For a structured grid that uses a DIS input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - ROW – This column represents the rows of the cells.
      - COL – This column represents the columns of the cells.
    - For a grid that uses a DISV input file, these columns will be:
      - LAY – This column represents the layers of the cells.
      - CELL2D – This column represents the CELL2D numbers of the cells.
    - If the model uses a DISU (unstructured discretization) file, the column will be:
      - CELLID – This column represents the node numbers of the cells.
- CONC – This column represents the constant concentration values. If time-series files are used as input, entering a time-series name instead of a numeric value can allow for values to be obtained from a time series.
- AUX – These columns represent the values of the auxiliary variables for each constant concentration, which previously may have been created if the AUXILIARY option was set. If time-series files are used as input, entering a time-series name instead of a numeric value can allow for values to be obtained from a time series.
- BOUNDNAME – This column represents the name of the constant concentration cells, and will appear if the BOUNDNAMES option was set. BOUNDNAME values are ASCII character variables that can contain as many as 40 characters. If it contains spaces within it, then the entire name will have to be enclosed within single quotes.

MF6 DSP Package

The Dispersion (DSP) Package dialog

The Dispersion (DSP) Package dialog is accessed by double-clicking on the DSP package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- XT3D_OFF – This deactives the XT3D method, to use the faster but less accurate approximation method. In some circumstances, the solution this provides may be fast and accurate. These could include when flow aligns with the model grid, when there is no mechanical dispersion, or when the longitudinal and transverse dispersivities are equal. This may also be useful in assessing the computational demand of the XT3D approach, by comparing run time differences with this option turned on or off.
- XT3D_RHS – This adds XT3D terms to the right-hand side, when possible. This uses less memory, but might require more iterations.
GRIDDATA section – This deals with the GRIDDATA block.
- Define – This allows data within the GRIDDATA section to be defined. When this is inactive in a tab, all of the options within that given tab are grayed out.
- Layered – When this is active, a numeric updown for the layers will become available.
- Drop-down and Constant/Factor – The drop-down in the GRIDDATA section has two options. The option selected will change the nature of the textbox to its right.
  - CONSTANT – This will change the textbox to the right to be representative of "Constant". If this is selected, the spreadsheet in the GRIDDATA section will be grayed out.
  - ARRAY – This will change the textbox to the right to be representative of "Factor". If this is selected, the spreadsheet in the GRIDDATA section will not be grayed out, and its cells will be editable.
- Dataset to Array... – This button brings up a Select Dataset dialog, where a single dataset can be selected for use in the GRIDDATA section. This will populate its spreadsheet. This option is grayed out if Define is not turned on.
- DIFFC – The DIFFC tab represents the effective molecular diffusion coefficients.
- ALH – The ALH tab represents the longitudinal dispersivities in the horizontal direction. When flow is strictly horizontal, these are the longitudinal dispersivities that will be used. When flow is neither strictly horizontal nor vertical, then the longitudinal dispersivity will be a function of both ALH and ALV. An ALH array is required when mechanical dispersion is represented (by specifying any dispersivity values).
- ALV – The ALV tab represents the longitudinal dispersivities in the vertical direction. When flow is strictly vertical, these are the longitudinal dispersivities that will be used. When flow is neither strictly horizontal nor vertical, then the longitudinal dispersivity will be a function of both ALH and ALV. An ALV array will be set set equal to an ALH array when its value is not specified and mechanical dispersion is represented.
- ATH1 – The ATH1 tab represents the transverse dispersivities in the horizontal direction. These are the transverse dispersivity values for the second ellipsoid axis. When flow is strictly horizontal and directed in the X direction (along a row for a regular grid), then these values control spreading in the Y direction. An ATH1 array is required when mechanical dispersion is represented (by specifying any dispersivity values).
- ATH2 – The ATH2 tab represents the transverse dispersivities in the horizontal direction. These are the transverse dispersivity values for the third ellipsoid axis. When flow is strictly horizontal and directed in the X direction (along a row for a regular grid), then these values control spreading in the Z direction. An ATH2 array will be set equal to an ATH1 array when its value is not specified and mechanical dispersion is represented.
- ATV – The ATV tab represents the transverse dispersivities when the flow is in the vertical direction. When flow is strictly vertical and directed in the Z direction, then these values control spreading in the X and Y directions. An ATV array will be set equal to an ATH2 array when its value is not specified and mechanical dispersion is represented.

MF6 DISV Package

The Discretization by Vertices (DISV) Package dialog

The Discretization by Vertices (DISV) Package dialog is accessed by double-clicking on the DISV package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DIMENSIONS – Turn on to make the DIMENSIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
- VERTICES – Turn on to make the VERTICES section visible.
- CELL2D – Turn on to make the CELL2D section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- LENGTH_UNITS
- NOGRB
- XORIGIN
- YORIGIN
- ANGROT
DIMENSIONS section – ...
- Number of layers (NLAY)
- Number of cells per layer (NCPL)
- Number of vertices (NVERT)
GRIDDATA section – ...
- Dataset to Array...
- Define
- Layered
- Constant
- TOP
- BOTM
- IDOMAIN
VERTICES section – ...
CELL2D section – ...

MF6 DISU Package

The Unstructured Discretization (DISU) Package dialog

The Unstructured Discretization (DISU) Package dialog is accessed by double-clicking on the DISU package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DIMENSIONS – Turn on to make the DIMENSIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
- CONNECTIONDATA – Turn on to make the CONNECTIONDATA section visible.
- VERTICES – Turn on to make the VERTICES section visible.
- CELL2D – Turn on to make the CELL2D section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- LENGTH_UNITS
- NOGRB
- XORIGIN
- YORIGIN
- ANGROT
DIMENSIONS section – ...
- Number of nodes (NODES)
- Number of connections and nodes (NJA)
- Number of vertices (NVERT)
GRIDDATA section – ...
- TOP
- BOT
- AREA
- IDOMAIN
CONNECTIONDATA section – ...
- IAC
- JA
- IHC
- CL12
- HWVA
- ANGLDEGX
VERTICES section – ...
CELL2D section – ...

MF6 FMI Package

The Flow Model Interface (FMI) Package dialog

The Flow Model Interface (FMI) Package dialog is accessed by double-clicking on the FMI package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- PACKAGEDATA – Turn on to make the PACKAGEDATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- FLOW_IMBALANCE_CORRECTION
PACKAGEDATA section – ...
- Let GMS determine the paths from the flow simulation when saving
  - Select Flow Simulation...
- Add Rows...
- FLOWTYPE
- FNAME

MF6 GWT Package

The Groundwater Transport (GWT) Model Name File dialog

The Groundwater Transport (GWT) Model Name File dialog is accessed by double-clicking on the GWT model under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- PACKAGES – Turn on to make the PACKAGES section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- LIST
- PRINT_INPUT
- PRINT_FLOWS
- SAVE_FLOWS
PACKAGES section – ...
- ftype
- fname
- pname

MF6 IST Package

The Immobile Storage and Transfer (IST) Package dialog

The Immobile Storage and Transfer (IST) Package dialog is accessed by double-clicking on the IST package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- SAVE_FLOWS
- SORPTION
- FIRST_ORDER_DECAY
- ZERO_ORDER_DECAY
- CIM FILEOUT
- CIM PRINT_FORMAT
GRIDDATA section – ...
- CIM
- THETAIM
- ZETAIM
- DECAY
- DECAY_SORBED
- BULK_DENSITY
- DISTCOEF

MF6 LKT Package

The Lake Transport (LKT) Package dialog

The Lake Transport (LKT) Package dialog is accessed by double-clicking on the LKT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DATA – Turn on to make the DATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- FLOW_PACKAGE_NAME
- AUXILIARY
- FLOW_PACKAGE_AUXILIARY_NAME
- BOUNDNAMES
- PRINT_INPUT
- PRINT_CONCENTRATION
- PRINT_FLOWS
- SAVE_FLOWS
- CONCENTRATION FILEOUT
- BUDGET FILEOUT
- TS6 FILEIN
- OBS6 FILEIN
DATA section – ...
- PACKAGEDATA
- PERIODS

MF6 MST Package

The Mobile Storage and Transfer (MST) Package dialog

The Mobile Storage and Transfer (MST) Package dialog is accessed by double-clicking on the MST package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- GRIDDATA – Turn on to make the GRIDDATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- SAVE_FLOWS
- FIRST_ORDER_DECAY
- ZERO_ORDER_DECAY
- SORPTION
GRIDDATA section – ...
- POROSITY
- DECAY
- DECAY_SORBED
- BULK_DENSITY
- DISTCOEF
- SP2

MF6 MVT Package

The Mover Transport (MVT) Package dialog

The Mover Transport (MVT) Package dialog is accessed by double-clicking on the MVT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- PRINT_INPUT
- PRINT_FLOWS
- SAVE_FLOWS
- BUDGET FILEOUT

MF6 MWT Package

The Multi-Aquifer Well Transport (MWT) Package dialog

The Multi-Aquifer Well Transport (MWT) Package dialog is accessed by double-clicking on the MWT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DATA – Turn on to make the DATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- FLOW_PACKAGE_NAME
- AUXILIARY
- FLOW_PACKAGE_AUXILIARY_NAME
- BOUNDNAMES
- PRINT_INPUT
- PRINT_CONCENTRATION
- PRINT_FLOWS
- SAVE_FLOWS
- CONCENTRATION FILEOUT
- BUDGET FILEOUT
- TS6 FILEIN
- OBS6 FILEIN
DATA section – ...
- PACKAGEDATA
- PERIODS

MF6 SFT Package

The Streamflow Transport (SFT) Package dialog

The Streamflow Transport (SFT) Package dialog is accessed by double-clicking on the SFT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DATA – Turn on to make the DATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- FLOW_PACKAGE_NAME
- AUXILIARY
- FLOW_PACKAGE_AUXILIARY_NAME
- BOUNDNAMES
- PRINT_INPUT
- PRINT_CONCENTRATION
- PRINT_FLOWS
- SAVE_FLOWS
- CONCENTRATION FILEOUT
- BUDGET FILEOUT
- TS6 FILEIN
- OBS6 FILEIN
DATA section – ...
- PACKAGEDATA
- PERIODS

MF6 SRC Package

The Mass Source Loading (SRC) Package dialog

The Mass Source Loading (SRC) Package dialog is accessed by double-clicking on the SRC package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- PERIODS – Turn on to make the PERIODS section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- AUXILIARY
- AUXMULTNAME
- BOUNDNAMES
- PRINT_INPUT
- PRINT_FLOWS
- SAVE_FLOWS
- TS6 FILEIN
- OBS6 FILEIN
PERIODS section – ...
- Period
- Define Period
- Delete Period
- Add Rows
- Delete Rows
- Plot All Periods
- Open Time Series
- Filter on Selected Cells
- LAY
- ROW

MF6 SSM Package

The Source and Sink Mixing (SSM) Package dialog

The Source and Sink Mixing (SSM) Package dialog is accessed by double-clicking on the SSM package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- SOURCES – Turn on to make the SOURCES section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- PRINT_FLOWS
- SAVE_FLOWS
SOURCES section – ...
- Set Up From Flow Model
- Add Rows...
- PNAME
- SRCTYPE

MF6 UZT Package

The Unsaturated Zone Transport (UZT) Package dialog

The Unsaturated Zone Transport (UZT) Package dialog is accessed by double-clicking on the UZT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- DATA – Turn on to make the DATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- FLOW_PACKAGE_NAME
- AUXILIARY
- FLOW_PACKAGE_AUXILIARY_NAME
- BOUNDNAMES
- PRINT_INPUT
- PRINT_CONCENTRATION
- PRINT_FLOWS
- SAVE_FLOWS
- CONCENTRATION FILEOUT
- BUDGET FILEOUT
- TS6 FILEIN
- OBS6 FILEIN
DATA section – ...
- PACKAGEDATA
- PERIODS

Arrays to Datasets

GWF-GWF Exchange

The Groundwater Flow (GWF) Exchange dialog

The Groundwater Flow (GWF) Exchange dialog is accessed by double-clicking on the GWF-GWF package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
- OPTIONS – Turn on to make the OPTIONS section visible.
- EXCHANGEDATA – Turn on to make the EXCHANGEDATA section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
OPTIONS section – Options and settings:
- AUXILIARY
- PRINT_INPUT
- PRINT_FLOWS
- SAVE_FLOWS
- CELL_AVERAGING
- VARIABLECV
- NEWTON
- GNC6 FILEIN
- MVR6 FILEIN
- OBS6 FILEIN
EXCHANGEDATA section – ...
- Add Rows...
- LAYM1
- ROWM1
- COLM1
- LAYM2
- ROWM2
- COLM2
- IHC
- CL1
- CL2
- HWVA

GWF-GWT Exchange

The Groundwater Transport (GWT) Exchange dialog

The Groundwater Transport (GWT) Exchange dialog is accessed by double-clicking on the GWF-GWT package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

Sections list – A list of sections that can be turned on or off:
- COMMENTS – Turn on to make the COMMENTS section visible.
COMMENTS section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.

MODFLOW 6 GWF/GWT Display Options

MODFLOW 6 GWF/GWF Display Options