Ecrin v4.20 - Doc v4.20.01 - © KAPPA 1988-2011
Saphir Guided Session #8 • SapGS08- 4/11
B02 • Minifrac analysis
The minifrac analysis is available using the ‘Minifrac’ button
in the ‘More tools’ control
panel as soon as a falloff is present in the extracted data. If several groups have been
extracted, only the falloff groups will be considered in the minifrac analysis.
Click on the ‘Minifrac’ button, this generates three new plots and adds the drawdown derivative
to the existing Loglog plot. The new plots are called ‘G-Function’, ‘Square root’ and ‘ACA’ plots,
we will use the first two to perform the post shut-in analysis and the last one for the after
closure analysis.
Fig. B02.1 • Minifrac analysis
B02.1 • Post Shut-in analysis
The ‘G-Function’ plot displays pressure P, derivative dP/dG and semi-log derivative G.dP/dG
versus G-Function and is aimed at finding the fracture closure point.
Maximize the plot, a new toolbar is now available,
.
The last five buttons activates the following minifrac functionalities:
Fit a straight line that passes by the origin to the semi-log derivative G.dP/dG.
Shift the dashed vertical line which represents the assessed closure point.
Change the value of the fracture growth exponent.
Change the smoothing parameter.
Far field permeability estimate calculator.
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