Please enable JavaScript to view this site.

ModelMuse Help

Navigation: Online Guide to MODFLOW > Groundwater Flow Process > Subsidence

SUB - Subsidence and Aquifer-System Compaction Package

Scroll Prev Top Next More

Abbreviation in Name file

SUB

Purpose

The  Subsidence and Aquifer-System Compaction package is used for simulating the drainage, changes in groundwater storage, and compaction of aquifers, interbeds and confining units that constitute an aquifer system. Delays in the release of groundwater from interbed storage, and thus delays in aquifer-system compaction, can be simulated. Delayed drainage and compaction in confining units can also be simulated.

Documentation

Höffmann, J., Leake, S.A., Galloway, D.L., and Wilson, A.M., 2003, MODFLOW-2000 Ground-Water Model--User Guide to the Subsidence and Aquifer-System Compaction (SUB) Package: U.S. Geological Survey Open-File Report 03-233, 44 p.

release.txt

Schmid, Wolfgang, and Hanson R.T., 2009, The Farm Process Version 2 (FMP2) for MODFLOW-2005 - Modifications and Upgrades to FMP1: U.S. Geological Survey Techniques in Water Resources Investigations, Book 6, Chapter A32, 102p. (https://pubs.er.usgs.gov/publication/tm6A32)

Hanson, R.T., Boyce, S.E., Schmid, Wolfgang, Hughes, J.D., Mehl, S.M., Leake, S.A., Maddock, Thomas, III, and Niswonger, R.G., 2014, One-Water Hydrologic Flow Model (MODFLOW-OWHM): U.S. Geological Survey Techniques and Methods 6–A51, 120 p., https://dx.doi.org/10.3133/tm6A51.

Related Packages

Interbed Storage package

SWT Subsidence and Aquifer-System Compaction Package

Supported in

MODFLOW-2000

MODFLOW-2005

MODFLOW-LGR

MODFLOW-CFP

MODFLOW-NWT

MODFLOW-OWHM

Other Notes

The Interbed Storage Package can not be used in the same model with the Subsidence and Aquifer-System Compaction Package.

Subsidence cannot be used in simulations in which stress periods other than the first are steady-state.

The Subsidence package cannot be used with the Sensitivity process.

Comment lines can be inserted into the SUB input file anywhere except where arrays are to be read by one of the array-reader subroutines (U2DREL or U2DINT).   Each comment line must have the "#" character as its first character and may be up to 200 characters in length.

The UZF package does not take into account changes in the land surface due to subsidence.

 

A property from Data Set 7 through 12 or 14 through 18 can either be defined there or by a parameter, but not both. So if parameter PTYP is used, then its corresponding data set item is not read.

See the Frequently Asked Questions for information on how to read data from binary files generated by MODFLOW.

Input Instructions

Input for the SUB Package is read from the file that has the type “SUB” in the name file. Optional variables are shown in brackets. All single-valued variables in data items 1, 15, and 16, layer assignments for systems of interbeds in data items 2 and 3, and material properties in data item 9 are read in free format. Data items 1, 2, 3, and 15 consist of at most one record. Two-dimensional arrays in data items 4-8 and 10-14 are read with MODFLOW-2000 utility array readers U2DREL and U2DINT. For instructions on use of array readers, refer to Harbaugh and others (2000).

FOR EACH SIMULATION

Data Set 0

[#Text]

Item 0 is optional—“#” must be in column 1. Item 0 can be repeated multiple times.

Data Set 1

[PARAMETER NSBP IPRNTFLG]

This optional item must start with the word “PARAMETER”

This item is only available in MODFLOW-OWHM.

 

Data Set 2

ISUBCB ISUBOC NNDB NDB NMZ NN AC1 AC2 ITMIN IDSAVE IDREST SUBLNK

(Enter integers for variables other than AC1 and AC2, which are floating-point variables.)

Data Set 3

[LN(NNDB)] if NNDB > 0

(Enter NNDB integers separated by one or more spaces or by commas.)

Data Set 4

[LDN(NDB)] if NDB > 0

(Enter NDB integers separated by one or more spaces or by commas.)

Data Set 5

[PARNAM PARTYP Parval NCLU]

Repeat Item 5 combined with the indicated repetitions of Item 6 NCLU times. Item 5 and 6 are not read if PARAMETER is not declared in Item 1 or NSBP=0.

This item is only available in MODFLOW-OWHM.

 

Data Set 6

[Layer Mltarr Zonarr IZ]

After each Item 5, repeat Item 6 NCLU times.

This item is only available in MODFLOW-OWHM.

 

Data Set 7

[RNB(NCOL,NROW)] U2DREL if NDB > 0 and NOT defined with PARTYP=“SRNB”

(One array for each of the NDB systems of interbeds)

The following five arrays are needed to describe the initial conditions and properties of each of the NNDB systems of no-delay interbeds. All of the arrays (items 8-12) for system 1 are read first; then all of the arrays for the remaining systems.

Data Set 8

[HC(NCOL,NROW)] U2DREL if NNDB > 0 and NOT defined with PARTYP=“NDHC”

Data Set 9

[Sfe(NCOL,NROW)] U2DREL if NNDB > 0 and NOT defined with PARTYP=“SFE”

Data Set 10

[Sfv(NCOL,NROW)] U2DREL if NNDB > 0 and NOT defined with PARTYP=“SFV”

Data Set 11

MODFLOW-2000, MODFLOW-2005, MODFLOW-NWT, MODFLOW-LGR, MODFLOW-CFP

[Com(NCOL,NROW)] U2DREL if NNDB > 0

 

MODFLOW-OWHM

[ComE(NCOL,NROW)] U2DREL if NNDB > 0 and NOT defined with PARTYP=“COME”

 

Data Set 12 MODFLOW-OWHM only

[ComV(NCOL,NROW)] U2DREL if NNDB > 0 and NOT defined with PARTYP=“COMV”

 

Data Set 13

[DP(NMZ,3)] if NDB > 0

(Use one record for each material zone. Data item includes NMZ records, each with a value of vertical hydraulic conductivity, elastic specific storage, and inelastic specific storage.)

The following six arrays are needed to describe the initial conditions and properties of each of the NDB systems of delay interbeds. All of the arrays (items 14-19) for system 1 are read first; then all of the arrays for the remaining systems.

Data Set 14

[Dstart(NCOL,NROW)] U2DREL if NDB > 0 and IDREST 0 and NOT defined with PARTYP=“DSTR”

Data Set 15

[DHC(NCOL,NROW)] U2DREL if NDB > 0 and IDREST 0 and NOT defined with PARTYP=“DHC”

Data Set 16

MODFLOW-2000, MODFLOW-2005, MODFLOW-NWT, MODFLOW-LGR, MODFLOW-CFP

[DCOM(NCOL,NROW)] U2DREL if NDB > 0

 

MODFLOW-OWHM

[DCOME(NCOL,NROW)] U2DREL if NDB > 0 and NOT defined with PARTYP=“DCME”

 

 

Data Set 17 MODFLOW-OWHM only

[DCOMV(NCOL,NROW)] U2DREL if NDB > 0 and NOT defined with PARTYP=“DCMV”

 

Data Set 18

[DZ(NCOL,NROW)] U2DREL if NDB > 0 and NOT defined with PARTYP=“SDZ”

Data Set 19

[NZ(NCOL,NROW)] U2DINT if NDB > 0

Data Set 20

[Ifm1 Iun1 Ifm2 Iun2 Ifm3 Iun3 Ifm4 Iun4 Ifm5 Iun5 Ifm6 Iun6 Ifm7 Iun7 Ifm8 Iun8 Ifm9 Iun9 Ifm10 Iun10] if ISUBOC > 0

(Data item 15 consists of one record with 12 integers separated by one or more spaces or by commas)

Data Set 21

[ISP1 ISP2 ITS1 ITS2 Ifl1 Ifl2 Ifl3 Ifl4 Ifl5 Ifl6 Ifl7 Ifl8 Ifl9 Ifl10 Ifl11 Ifl12 Ifl13 Ifl14 Ifl15 Ifl16 Ifl17 Ifl18 Ifl19 Ifl20 Ifl21] if ISUBOC > 0.

Data item 16 consists of ISUBOC records with 17 integers separated by one or more spaces or by commas. Please see the section entitled “Package Output” for a detailed explanation of the use of data item 16.

The variables ISP1, ISP2, ITS1, ITS2, and Ifl1 through Ifl13 are used to control printing and saving of information generated by the SUB Package during program execution. The use of some of these variables is explained in more detail in the section entitled Package Output. The default condition for flags Ifl1 through Ifl13 is to not print or save the indicated information, except for printing budgets for no-delay interbeds for the last time step of each stress period.