Young's Static Modulus for Three Layers
Poisson's Ratio for Three Layers
Vertical Biot for Three Layers
Closure Stress for Three Layers
These crossplots display closure stress and related inputs for a smplified three layer model. The GOHFER (Grid Oriented Hydraulic Fracture Extension Replicator) total stress equation is used with horizontal Biot poroelastic constant set to one.
Inputs are highlighted in yellow and outputs are in green. Start by entering reservoir true vertical depth, overburden stress gradient and pore pressure gradient. Next, enter values for Young's static modulus, Poisson's ratio and vertical Biot's poroelastic contant, for all three layers.
To calibrate closure stress , field measured data are required. Enter the field measured closure stress for the reservoir layer and the associated data point will be plotted on the closure stress depth plot. Finally, adjust the regional horizontal strain or stress offset values to create a match between the calculated closure stress and the field measured value, for the reservoir layer. Generally the regional horizontal strain offset approach is favoured.
Outputs include closure stress and closure stress gradient for all three layers.