Figure F72. Motion Decoupled Hydraulic Delivery System (MDHDS) Deployment 2 pressure vs. time profile, Site U1402. The MDHDS was deployed at 745 m DRF. Time elapsed is from the moment the penetrometer is driven into the formation. As the latch releases on the MDHDS at 0 s, the tip of the temperature-dual-pressure probe (T2P) is driven into the formation by its own mass (1); the T2P is driven farther into the formation as the MDHDS is pressured up a second time causing the tip and shaft pressure to spike from 0 to 60 s (2). Circulation pumps are then turned off (3), simultaneously causing a minor decrease in pressure and reducing measurement noise substantially at 60 s. The pressure dissipates as expected with the exception of a brief increase in pressure (and acceleration) caused by the circulation pumps turning on momentarily at 2200 seconds (4).
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