It seems so obvious: most mines involve cutting into rock. And rock is fractured. Therefore the stability and groundwater flow patterns of the mine opening, whether open pit or underground, will be controlled by the fractures.

The only place I can find on the web that provides products and services based on this simple observation is FracMan. They are a part of Golder Associates, although they do so many things, I can find no link on Golder’s site to FracMan. Seems FracMan is a three-person group: Bill Dershowitz in Washington, Steve Rogers in Nottinghamshire, and Isabelle Staub in Stockholm. .

They appear to give workshops on their technical approach, although the last one was in 2001, so maybe they are now too busy consulting. Certainly they list consulting services in these areas:

The FracMan software includes:

  • FracSys (Data Analysis)
  • FracWorks XP (3D DFN Structural Modeling and Visualization)
  • MAFIC (Finite Element Flow and Transport Modeling)
  • PAWorks (Pathways Analysis)
  • FraCluster (Compartmentalization and Cluster Analysis)
  • FracView (Visualization and Software Linking)

From the point of view of one interested in groundwater in mining, MAFIC is the heart. Here is how they describe it:

MAFIC (Matrix and Fracture Interaction Code) uses the finite element method to solve for flow and transport through FracWorks geological models. MAFIC idealizes fractures using triangular finite elements, and can alternatively represent fractures using 1-D pipe elements. MAFIC provides for dual porosity interaction using either quadrahedral finite elements or a 1-D approximation based on the Warren and Root pseudo-steady state approximation. MAFIC uses a pre-conditioned conjugate gradient solver, with variable bandwidth matrix storage. MAFIC simulates solute transport and heat transport using a convective particle tracking approach. Solute dispersion is simulated stochastically using orthogonal, normally distributed, lateral and transverse dispersion vectors. MAFIC solute transport includes matrix diffusion, mineral-specific retardation, and sorption features. MAFIC was designed to simplify input data requirements while providing maximum flexibility for the designation of boundary conditions. Input files may be specified by the user or generated by the FracMan fracture network simulation package. MAFIC is generally used for fracture networks of 10 to 10,000 fractures, although it and has been applied for networks of up to 100,000 fractures using triangular finite elements and 300,000 fractures using pipe elements.

There is plenty on the web from Google via keyword “fracman”. Here are some great powerpoint presentations to while away the idle hours (some are large and take a while to download, but are worth the wait.)

For something older and more profound, see the 1994 publication Compendium of fracture flow models by D. M. Diodata of Argonne National Laboratory. Finally, I cannot resist copying this magnificent figure that captures it all. I have e-mailed them asking permission to copy and post.