SUB - Subsidence and Aquifer-System Compaction Package

GMS version 9.0 has added support for the SUB package in MODFLOW.  The SUB package was developed by the USGS to simulate aquifer compaction and land subsidence.  The SUB package simulates compaction of interbeds including both elastic (recoverable) and inelastic (not recoverable) compaction. It also includes the ability to simulate interbeds where drainage from the interbed is immediate (no-delay) or delayed.

In GMS you can add interbeds and set interbed attributes using the conceptual model interface.  You can also add and edit interbeds through a grid interface.  The grid interface also includes the ability to setup SUB package output.  When SUB package vertical displacement has been set to be saved to a file, a VerticalDisplacement data set is added to the model solution in the GMS project explorer as shown above.

To learn more about using the SUB package in GMS, a new tutorial will be available in the GMS learning center when GMS 9.0 is released. Documentation on the wiki is available now.