Discussion on Field Injectivity Tests During Drilling

Excerpt

Fracture pressure (i.e. fracture initiation or propagation pressure) and minimum horizontal stress (Shmin) are critical parameters for drilling and completion engineering. They are required for studies of wellbore instability, lost circulation, hydraulic fracturing, sand production, reservoir compaction and subsidence, and so on. There are some indirect methods for prediction of fracture pressure and Shmin from well logging data (Zoback 2010). However, these methods are usually based on simplified and questionable assumptions and are only reliable in areas where they have been well calibrated using sufficient measured data (Zoback 2010). Field injectivity tests, that fracture rock and measure stress directly, therefore, are regarded as the most reliable technique for determination of fracture pressure and Shmin (Fjar et al. 2008). …