iMOD Forum

Include (discontinuous) layers with different depths (bottom and top)

E Breejen, modified 2 Years ago.

Include (discontinuous) layers with different depths (bottom and top)

Youngling Post: 1 Join Date: 10/11/22 Recent Posts
I would like to include the subsurface of Groningen in my iMOD-model to model Groundwater flow and calculate hydraulic head changes due to groundwater extraction..

I have a 3D model of 40-40km and a depth of 400m. 

I have discontinuous layers in my model: younger layers have filled the gaps (incisions) of the older/deeper layers below. The model doesn’t understand these "gaps" where the layers above should fill those “gaps” of the layers below (see picture). 

How should I tackle this situation to build a realistic model?

Thank you,
Ed, Master student hydrology
Frans Roelofsen, modified 2 Years ago.

RE: Include (discontinuous) layers with different depths (bottom and top)

Padawan Posts: 51 Join Date: 11/11/13 Recent Posts
At the moment we at Deltares only build ground water models using MODFLOW 6. In Modflow 6 all models are full 3D and the advantage is that in MODFLOW6 allows layers with thickness = 0.  In the former Modflow2005 thickness of 0 was not possible. Then we had to give none exitsing layers  a dummy thickness.
So in Modflow6 your model with gaps are possible. So you just set the TOP elevation of non existing layers equal to the BOT elevation