Formation fracture characterization from post shut-in acoustics and pressure decay using a 3 segment model

A computer program stored in a computer readable medium, the program comprising logic operable to cause a programmable computer to perform actions on measurements of pressure made in a well after stopping pumping (shut in) a fracture treatment into the well, the actions, comprising:

• determining a first time after shut in where after a decrease in measured pressure is caused by fluid leak off in a fracture;
• determining a second time after shut in where after the decrease in pressure is caused by fluid leak off, fracture growth and fluid pressure equilibration in the fracture;
• determining a third time after shut in where after the decrease in pressure is caused by fluid leak off, fracture growth, fluid pressure equilibration in the fracture and pressure drop in a near wellbore zone;
• and
• determining values of fluid efficiency, minimum stress and net pressure which result in a calculated pressure with respect to time matching the pressure measurements within a predetermined threshold, wherein calculating pressure with respect to time is based on causes of pressure drop in segments corresponding to time between (i) the third time and the second time, (ii) the second time and the first time, and (iii) after the first time.