ModelMuse Help

Options-- is a 1-line character record that may contain one or more keyword codes that control options in MODPATH and MODPATH-PLOT. A blank line must be included for this data item even if none of the keyword options is used. Keywords that only affect MODPATHPLOT are ignored by MODPATH.

XSECTION indicates that the model is a 1-row cross section for which IBOUND and the Grid Unit Array (GUA) should each be read as a single, 2-dimensional array with dimensions of NCOL and NLAY.

COMPACT indicates that MODPATH should generate endpoint, pathline, and time series files as text files using the global node number to indicate cell location. If COMPACT is omitted, the cell location is designated using the row-column-layer grid indices (as in previous versions of MODPATH).

BINARY indicates that the endpoint, pathline, and time series files will be generated by MODPATH in binary form. This keyword also is required by MODPATH-PLOT in order to correctly read binary versions of these files.

METERS indicates to MODPATH-PLOT that distances are in meters. The METERS parameter only affects the label on the distance scale produced by MODPATH-PLOT. It has no affect on computations produced by MODPATH. If the option METERS is not specified, MODPATH assumes that length units are in feet. If a length unit other than feet or meters is used in MODFLOW, the scaling performed by MODPATH-PLOT will not be correct.

WT(OFF) indicates that the water table profile will not be drawn on true cross section plots. If none of the three "WT" options is specified, MODPATH-PLOT draws the water-table profile as a solid line with the same color used for drawing contour lines.

WT(DOTTED) indicates that the water-table profile will be drawn as a dotted line on true cross section plots.

WT(DASHED) indicates that the water-table profile will be drawn as a dashed line on true cross section plots.

•0 indicates confined

•not 0 indicates convertible or water table

Read one array for each layer

In the current version of MODFLOW, the IBOUND array is read one layer at a time by specifying a 2-D array of data for each layer in the grid. In this version of MODPATH, if the model is a 1-row cross section and the keyword XSECTION is specified in the options data record (Main data file item 2), the IBOUND array will be read as a single 2-D array for the entire cross section. Future versions of MODFLOW may support the XSECTION option for IBOUND data in cross sectional models.

If this IS NOT a 1-row cross section, read a 2-D array of data for each layer by repeating the following data sequence for each layer:

3. IBOUND(NCOL,NROW)

FORMAT: 2-D integer array reader (U2DINT)

Or, if this IS a 1-row cross section with XSECTION specified, read a single 2-D array for the cross section:

3. IBOUND(NCOL,NLAY)

FORMAT: 2-D integer array reader (U2DINT)

IBOUND-- is the boundary array containing cell type codes.

•IBOUND < 0 : specified head cell

•IBOUND = 0 : inactive cell

•IBOUND > 0 : active cell

The absolute value of IBOUND is the zone code, which is used by MODPATH-PLOT to determine the color of pathlines and particle points. MODPATH requires that the absolute value of IBOUND be less than 1000.

Read one array for each layer

REPEAT THE FOLLOWING DATA IN SEQUENCE FOR EACH LAYER:

5A. POR(NCOL,NROW)

FORMAT: 2-D real array reader (U2DREL)

If the model layer has a quasi-3d confining layer, then

5B. PorCB(NCOL,NROW)

FORMAT: 2-D real array reader (U2DREL)

POR-- is the array containing porosity values for a model layer.

PorCB-- is the array containing porosity values for a quasi-3D confining layer associated with the model layer. If a model layer includes a quasi-3d confining layer, the PorCB array immediately follows the POR array for that model layer.

TBEGIN-- is the time value assigned to the beginning of the MODFLOW simulation. Any convenient value may be specified, including values less than zero.