Well Control - Abnormal pore pressures For exploratory well, the prediction of abnormally pressured formations can be difficult. Correlation with nearby wells will provide the most reliable information. Before drilling a wildcat, seismic data will generally be the only source of information regarding abnormal pore pressures.
Different indications of abnormal pore pressures will be observed in clastic and impermeable formations:
Indications of abnormal pressures in clastic formations (e.g. unconsolidated sands):
- Actual kick
- Drop in circulating pressure (Good).
- Increased drilling rate, called a "drilling break", (Good).
- Increased pit level (Good, but . . .