Figure F7. Characteristic deployments of Davis-Villinger Temperature-Pressure Probe (DVTPP) and temperature/dual pressure (T2P) probe. A. Type I deployment showing typical pressure record for a penetration test with clear pressure buildup and clean pressure dissipation. B. Type II deployment showing dramatic drop in pressure caused by decoupling of the drill string from the tool. Type II deployments can either show pressure decaying toward in situ pressure after the pressure drop (Type IIA) or pressure building to in situ pressure after the pressure drop (Type IIB). C. Type III deployment showing abrupt and erratic changes in pressure during the dissipation phase (“leak” deployment). Type III deployments include unsuccessful deployments resulting from hydraulic leaks, electronics failure, or tool damage and communication with borehole fluid.
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