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doi:10.2204/iodp.proc.308.203.2008

Appendix B

Temperature/​dual pressure probe

This appendix presents the T2P deployments made during Expedition 308 in four parts: (1) instruments used; (2) temperature calibration; (3) pressure calibration; and (4) detailed description of each T2P deployment. Figures showing pressure, temperature, and TrueView data for each T2P deployment are in the “APP_B” folder in “Supplementary material.”

Instruments

During Expedition 308, two types of penetrometer tips (Fig. F4), two data loggers, six pressure transducers, and five thermistors were used in combination to form the T2P probes that measured the formation pressure and temperature (Table T1).

Temperature calibration

Temperature calibrations were carried out on the data logger and thermistor separately. The data logger response to resistance was determined using a highly stable resistance box that simulates the resistance variation of the thermistor over its full temperature range. The calibration coefficients of the data logger were provided by the USIO prior to the expedition (Table AT21A). Table AT21B presents the commercial calibration of the thermistors prior to the cruise. Accuracy of the presented data is between –40° and 125°C. The Steinhart-Hart relationship is used to describe the temperature as a function of the thermistor resistance (Table AT21A) (Davis et al., 1997).

Pressure calibration

The T2P measures pore pressure with steel pressure transducers. The force on the sensing element due to the pressure results in a deformation of the sensing element and a change in the output signal.

Onboard calibration

Five out of six pressure transducers were calibrated using a witness pressure transducer provided by the USIO and a high-pressure oil pump in the downhole tools laboratory on the drillship prior to deployment. We ran the pump pressure from atmospheric pressure to 5000 psi and then stepped down to atmospheric pressure. The hysteresis was insignificant (Fig. AF1). The calibration curve is a straight line that can be characterized by its slope and its intersection on the y-axis (Fig. AF1; Table AT22).

Problems in the pressure calibration

All transducers were flooded with seawater whenever the tip of the T2P was broken. The seawater that leaked into the transducer weakened the insulation of the circuit inside the transducer, and the transducers became unstable, rendering the original pressure calibrations invalid.

To remove the moisture and stabilize the pressure transducers on the drill ship, the transducers were oven-dried at up to 60°C for up to 24 h before reuse. After oven drying, the slope of the calibration curve showed no significant change, but the intersection on the y-axis was subject to change (Table AT22). We did not recalibrate the transducers each time after being flooded. Therefore, we needed a systematic approach to correct any potential errors related to the change of the intersection as a result of oven drying.

Furthermore, analysis of pressure data calibrated according to the onboard calibrations showed that certain transducers were very sensitive to operating temperature. As an example, for onboard pressure calibration of T2P Deployment 1 (a tool test in water column) (see FIGUREB7_T2P_DEPLOY1.XLS in the “APP_B” folder in “Supplementary material”) the measurements were made at temperatures from 4° to 27°C. The tip pressure reading was in good agreement with the hydrostatic pressure calculated by assuming an average fluid density of 1.024 g/cm³. The shaft pressure reading matched the tip pressure closely at ~20°C, the temperature at which the transducers were calibrated. However, at significantly colder temperature, there was discrepancy between the tip and shaft pressures. The discrepancy varied with water temperature, up to 0.6 MPa at ~5°C. In this example, the shaft pressure transducer was much more sensitive to temperature than the tip transducer.

The “compensated temperature range” of the T2P pressure transducers is from 25° to 235°C. Out of this range, the slope (S) and intersection (I) of the calibration curve are subject to change because of variation in temperature (Fig. AF2). The onboard calibrations were done at the room temperature of the downhole tools laboratory on the vessel. These calibrations are not sufficient to describe the behavior of the transducers over the operating temperature range of the tool. Therefore, the temperature influence on the calibration curve must be tested to achieve accurate pressure calibration.

Postcruise calibration

Two pressure transducers were lost during postcruise shipment between laboratories. We checked the performance of the four available transducers before the recalibration. They were not stable and performed differently on different channels and data loggers. This was similar to the behavior observed immediately after transducers were flooded on the ship. We interpret this as being caused by the salt left in the transducers when they were flooded during deployments.

To correct for this problem, the transducers were baked at 55°C in an oven prior to recalibration to stabilize the transducers. Three of the four available transducers were very stable after oven drying.

In March 2007, we recalibrated the T2P pressure transducers using the same deadweight tester that was used to verify the calibrations of the DVTPP pressure transducers (see “Appendix A”). Calibrations were conducted at controlled temperatures to explore the influence of temperature on the slope and intersection of the calibration curve.

We ran the deadweight tester pressure from atmospheric pressure to 4015 psi and then stepped down to atmospheric pressure. The hysteresis was insignificant and the calibration curves were straight lines (Fig. AF3). No significant difference was observed between loggers Sn2 and Sn4 or between the tip pressure channel and the shaft pressure channel.

The results show that the slope and intersection of the calibration curve are linear functions of temperature (Figs. AF4, AF5, AF6). These relationships allow us to confidently interpret the calibration coefficients (slope and intersection of the calibration curve) for any given temperature within the range.

Recalibration of the T2P pressure data

We present the T2P deployment in the water column (T2P 1) to illustrate how we recalibrated the T2P pressure data using the postcruise calibrations (see FIGUREB7_T2P_DEPLOY1.XLS in the “APP_B” folder in “Supplementary material”). The two pressure transducers (S50-73 at the tip and Z59-72 at the shaft) were recalibrated under controlled temperatures. We used the temperature measured at the T2P tip thermistor to determine the calibration coefficients from the trendlines in Figures AF4 and AF5. We then applied the calibration coefficients to calculate the pressure from the transducer reading.

Neither of the calculated tip and shaft pressures match the hydrostatic pressures at the tool stops. We interpret this is caused by changes of the intersection due to oven drying (Table AT22). The offset from hydrostatic pressure is a constant value regardless of the operating temperature for both transducers. This suggests that the change in the intersection caused by the effects of oven drying is constant for any given deployment (e.g., a constant vertical shift of the I-T relationship presented in Figs. AF4B, AF5B, and AF6B).

The offset was corrected by matching the tip and shaft pressure records to the hydrostatic pressure at tool stops. After this correction, the tip pressure matches the shaft pressure very well. The hydrostatic pressures at tool stops are calculated from an assumed seawater density of 1.024 g/cm³ in which the atmosphere pressure is not accounted.

For the three pressure transducers not recalibrated under controlled temperatures, we applied the calibration coefficients obtained from the onboard calibration tests (Table AT22). We then compared these to the pressure data of one of the recalibrated transducers (S50-73, S50-75, and Z59-72). We took the difference between the tip and the shaft pressures as a function of the temperature measured at the probe tip. The temperature influence and the shift of the intersection (a constant value) were then compensated by applying this function (see FIGUREB15_T2P_DEPLOY8.XLS and FIGUREB22_T2P_DEPLOY16.XLS in the “APP_B” folder in “Supplementary material”).

T2P deployment procedure

The deployment procedure of the T2P is similar to that of the DVTPP (see “Appendix A”). We integrate TruView data, the shipboard T2P Deployment Log Sheet (see the “DOWNHOLE” folder in “Supplementary material”), and pressure and temperature records to define operation events and understand field measurements.

T2P deployments during Expedition 308

Deployment 1: Hole 1319A, tool test in water column

Deployment 1, completed in the water column prior to drilling, was the first sea deployment of the T2P probe. The deployment was intended to pressure test the T2P probe, to check the pressure transducer calibrations, and to confirm that the T2P probe could successfully pass through the lockable flapper valve (LFV) of the BHA.

The time-event log for T2P Deployment 1 is illustrated in Table AT23, and a graphical representation of the pressure and temperature records is illustrated in FIGUREB7_T2P_DEPLOY1.XLS in the “APP_B” folder in “Supplementary material.” The T2P was lowered until the tip was 511 meters below sea level (mbsl), where a hydrostatic reference was recorded for 2 min. The tool was then lowered until the tip was at 1011 mbsl for another 2 min reference. The T2P probe was then lowered through the LFV. The T2P probe tip reached a maximum depth of 1387.5 mbsl (42.1 m above seafloor), where a 7 min reference was recorded. References were also taken during retrieval of the T2P probe when the tip was at 1010 mbsl and at 511 mbsl. No drilling fluid was circulated during the deployment.

The tool test was successful. The tool recorded pressure and temperature for the entire deployment and successfully passed through the LFV. The temperature record showed a downhole decrease in temperature to 4.58°C at 1387.5 mbsl.

Deployment 2: Hole U1319A, 80.5 mbsf

Table AT24 and FIGUREB9_T2P_DEPLOY2.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 2. Traveling block position data are not available for this deployment. The bit depth data dramatically shifted during this deployment. Drilling fluid circulation was stopped when taking the hydrostatic reference, when pushing the probe into the sediment, and for the first 12 min the T2P probe was in the sediment. Fluid circulation resumed 12 min after the penetration at 14 strokes per minute (spm). Corresponding to the onset of fluid circulation, both the tip and shaft pressures increased very slightly (<0.01 MPa).

The temperature and pressure records increased when the CDS was latching into position (Table AT24). This response suggests the tool entered the formation while positioning the CDS to the retracted position. When the drill bit was lowered to insert the tool, it recorded a second temperature and pressure increase. Pressure and temperature records varied during the penetration process. We believe these variations were due to variations of the soil properties. After 35 min in the formation, pressure at the tip was 15.71 MPa, whereas the shaft recorded pressure of 16.35 MPa. Extrapolation of the pressure records may provide an estimate of the in situ pressure. The temperature record provided an in situ formation temperature of 7.23°C at the end of the deployment.

When the T2P probe was recovered on the rig floor, the shroud was not covering the tip. The tip of the tool was damaged and the themistor was missing. The drive tube was bent slightly. We interpret that the shroud never reseated over the tip during retrieval of the tool. Damage of the tip was interpreted to result from bending of the tip during penetration followed by a straightening of the tip when the T2P probe was pulled through the LFV in the BHA. Most likely, the T2P probe and drive tube were damaged because the T2P probe did not enter the sediment vertically. To achieve vertical penetration, future deployments occurred with the drill bit <2 m off BOH instead of 12 m.

Deployment 3: Hole U1320A, 126.3 mbsf

Table AT25 and FIGUREB10_T2P_DEPLOY3.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 3. In contrast to Deployment 2, Deployment 3 used the tapered needle probe and was initiated with the drill bit ~1 m off BOH. These modifications were done to decrease the chance for bending or breaking the needle probe. The quality of the bit depth data is poor. The absolute bit depth value is not reliable. To explore the bit movement during the deployment, the bit depth data have to be used together with Table AT25.

The T2P probe recorded temperature and pressure at the tip, whereas the shaft transducer did not record any data during the deployment. The temperature and pressure records increased while positioning the CDS to retracted position. When the drill bit was lowered to insert the tool, it recorded a second temperature and pressure increase. The tip pressure decreased abruptly when the drill bit was lifted. The fluid circulation resumed at 10 spm 5 min after penetration. No significant pressure and temperature responses were observed as a result of the onset of fluid circulation. Pressure dissipation was recorded at the tip until the probe was pulled out of the formation. The last recorded pressure was 16.27 MPa. Extrapolation of the pressure records will provide an estimate of the in situ pressure. The temperature decay was continuous and provided an in situ formation temperature of 6.99°C.

Deployment 4: Hole U1320A, 213.0 mbsf

Table AT26 and FIGUREB11_T2P_DEPLOY4.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 4. Deployment 4 used the straight needle probe. Operational procedures were similar to Deployment 3 except we did not use the drill string to push the T2P into the formation. Instead, we used the weight of the tool to push the tool into the formation. The tip pressure and temperature recorded spikes during penetration by the tool weight, whereas the shaft pressure did not record any penetration response. This indicates that the shaft pressure port did not go into the formation throughout the deployment. Fluid circulation resumed 6 min after the insertion spike, causing slight increases in both pressure and temperature. The final tip pressure was 17.19 MPa, the same as the shaft pressure. This suggests that the borehole fluid communicated with the tip pressure because of the short penetration distance (<0.25 m). The temperature reached an equilibrium value of 8.99°C. The temperature measurement may be subject to the influence of the borehole fluid.

Deployment 5: Hole U1324B, 51.3 mbsf

Table AT27 and FIGUREB12_T2P_DEPLOY5.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 5. The bit depth data shift dramatically, whereas the bit movement directions match the bit movements recorded in the T2P log sheet. To explore the bit position during the deployment, the bit depth data should be used together with Table AT27.

The BHA was positioned 0.5 m off BOH before the CDS latch-in. The temperature and pressure records increased while positioning the CDS to the retracted position. According to the tool dimensions, the T2P tip went into the formation by ~0.6 m at the latch-in position. The drill bit was lowered to 0.25 m off BOH at the end of penetration. The tool only recorded slight temperature and pressure increases due to the 0.25 m further insertion. The fluid circulation resumed 10 min after the penetration at 9 spm. Corresponding to the onset of fluid circulation, both the tip and shaft sensors recorded a slight pressure increase (<0.05 MPa). The tip and shaft pressures were generally constant during the dissipation phase. The tip had a final pressure of 11.37 MPa, and the shaft had a final pressure of 11.65 MPa. The temperature record continuously decayed to an equilibrium temperature of 5.78°C.

Upon pulling the tool out of the formation, all sensor readings were lost. At the rig floor, it was noted that the tip was bent and the thermistor and bottom porous stone were missing from the tool. We believed the tool may have been bent during penetration and then broken during the pullout when all sensor readings were lost. The pressure and temperature measurements should be viewed cautiously because of the damage incurred during the deployment.

Deployment 6: Hole U1324B, 89.3 mbsf

Table AT28 and FIGUREB13_T2P_DEPLOY6.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 6. The pressure and temperature records showed three spikes. The first spike occurred when the tool landed in the BHA, the second pulse occurred when the tool was pushed into the formation, and the third pulse occurred when circulation began while the tool was in the sediment. The shaft pressure reading continuously dissipated to its end value of 12.09 MPa. The tip pressure was not smooth and went close to or below the hydrostatic pressure after each pulse. We interpreted that there was an internal hydraulic leak at the tip. The temperature record was reasonable after the first two pulses, whereas it showed a rapid decrease after the third pulse. The last temperature reading was 5.74°C, which was even lower than the borehole fluid temperature (5.98°C) that was recorded prior to the first spike. We use the temperature data after the second spike to constrain the in situ temperature.

Deployment 7: Hole U1324B, 117.8 mbsf

Table AT29 and FIGUREB14_T2P_DEPLOY7.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 7. Similar to Deployment 6, the pressure and temperature records all showed responses to latching of the tool in the BHA, pushing into to the formation, and turning on circulation while in the formation. The internal leak at the tip pressure was not identified and repaired in Deployment 7. The shaft pressure reading had a continuous dissipation curve to its end value of 12.84 MPa after the third spike. The temperature record exhibited a type decay curve and provided an in situ temperature of 7.00°C.

Deployment 8: Hole U1324B, 136.3 mbsf

Table AT30 and FIGUREB15_T2P_DEPLOY8.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 8. The shaft pressure was not stable during this deployment, with multiple abrupt increases and decreases in pressure that were not associated with deployment events. The tip pressure and temperature records showed responses to latching of the tool in the BHA, pushing into to the formation, and backing-off the drill bit after penetration. The hydraulic leak at the tip pressure resulted in erratic dissipation curve. The temperature decay was smooth and provided an in situ temperature of 7.35°C. The tool was disassembled and reassembled after this deployment because of the poor pressure readings on both transducers.

Deployment 9: Hole U1324B, 368 mbsf

Table AT31 and FIGUREB16_T2P_DEPLOY9.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 9. This deployment recorded large pressure and temperature increases with the landing of the tool in the BHA. After a short period of decay, the tool was pulled out of the formation by pulling the wireline up. The pressure abruptly dropped to the borehole fluid pressure. The temperature increased abruptly first and then decreased to the borehole fluid temperature. The pressure and temperature had similar responses when pushing the tool into the formation. The abrupt pressure decrease was caused by backing-off the drill bit. The pressure and temperature records suggest that the tool was measuring the pressure and temperature of the borehole fluid. No in situ conditions can be ascertained from this deployment.

Deployment 10: Hole U1324B, 394.5 mbsf

The connection between the sensors and the data acquisition system had poor contact. This precluded collection of any data.

Deployment 11: Hole U1324B, 593.2 mbsf

Table AT32 and FIGUREB17_T2P_DEPLOY11.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 11. All connections were cleaned and the tool was reassembled because of the communication problem during Deployment 10. Deployment 11 was a test of the sensors and data acquisition system and did not involve pushing the probe into the sediment. The coreline depth and hook load data were not reliable during this deployment. The tip pressure showed excellent agreement with the shaft pressure. Two pressure decreases occurred in the tip pressure. These may have been caused by the tip being partly embedded in the sediment, whereas the shaft had not penetrated the formation. Overall this deployment confirmed that the electronic failure had been fixed.

Deployment 12: Hole U1324C, 50 mbsf

Table AT33 and FIGUREB18_T2P_DEPLOY12.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 12. The bit depth data had a dramatic shift and was not reliable. To explore the bit movement during the deployment, the bit depth data should be used together with Table AT33. The temperature and pressure records increased while positioning the CDS to the retracted position. When the drill bit was lowered to insert the tool, further temperature and pressure responses were recorded. Pressure and temperature records varied during the penetration process. These variations were due to variations of the sediment properties. The tip and shaft pressures decreased when the BHA was lifted; however, the magnitude of the decreases was small (<0.1 MPa). At the same time, the thermistor recorded a rapid increase in temperature. Fluid circulation resumed 8 min after the penetration at 10 spm. Corresponding to the onset of fluid circulation, both the tip and shaft pressures slightly increased. Then all sensors recorded a gradual dissipation. The tip measurement had an end value of 11.21 MPa. The shaft measurement had an end value of 11.56 MPa. Extrapolation of the pressure records will provide an estimate of the in situ pressure. The temperature decayed to an equilibrium temperature of 5.66°C.

Deployment 13: Hole U1324C, 100 mbsf

Table AT34 and FIGUREB19_T2P_DEPLOY13.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 13. All sensors had significant increases associated with pushing the tool into the sediment. The tip and shaft pressures decreased when the BHA was lifted, whereas the magnitude of the decrease was much larger at the tip. As the same time, the thermistor recorded a small increase in temperature. All sensors recorded a gradual dissipation. The tip had an end value of 11.93 MPa, and the shaft had an end value of 12.39 MPa. Extrapolation of the pressure records will provide an estimate of the in situ pressure. The temperature decayed to an equilibrium temperature of 6.65°C.

Deployment 14: Hole U1324C, 150 mbsf

Table AT35 and FIGUREB20_T2P_DEPLOY14.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 14. Similar to Deployment 13, pressure and temperature increased with insertion into the formation, followed by dissipation curves. All sensors recorded two perturbations while in the formation that could not be associated with any deployment event. After the last perturbation, the shaft pressure continued along a normal dissipation curve, whereas the tip showed a larger pressure decrease followed by a pressure increase. The tip measurement had an end value of 12.69 MPa. The shaft measurement had an end value of 13.10 MPa. The pressure records likely can be used to evaluate the in situ pressure. The temperature (7.57°C) appeared to be in equilibrium with the formation prior to pulling the tool out off BOH.

Deployment 15: Hole U1324C, 200 mbsf

Table AT36 and FIGUREB21_T2P_DEPLOY15.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 15. The temperature and pressure records increased while positioning the CDS to the retracted position. When the drill bit was lowered to insert the tool, it recorded further temperature and pressure responses. The tip and shaft pressures rapidly decreased when the BHA was backing-off the BOH. At the same time, the thermistor recorded a rapid increase in temperature. The shaft then continued along a normal dissipation curve, whereas the tip showed a pressure rebound followed by a gradual dissipation. The tip measurement had an end value of 14.09 MPa. The shaft measurement had an end value of 14.44 MPa. The pressure records can be used to evaluate the in situ pressure. The temperature decayed to an equilibrium temperature of 8.58°C.

All sensors lost communication with the data acquisition unit during retrieval of the tool from the formation. When the tool reached the rig floor, the tip was bent and the drive tube was loose. The loose drive tube most likely caused the failure to record data during the retrieval as the sensor cables were routed through the drive tube where they were connected with the data acquisition unit.

Deployment 16: Hole U1324C, 300 mbsf

Table AT37 and FIGUREB22_T2P_DEPLOY16.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 16. The temperature and tip pressure records increased while positioning the CDS to the retracted position. When the drill bit was lowered to insert the tool, it recorded further temperature and pressure responses. Pressure and temperature records varied during the penetration process. These variations were due to variations of the soil properties and penetration rate. The pressure and temperature sensors recorded continuous dissipation curves. The end temperature of 10.29°C was equilibrated with the formation. The end shaft pressure was 15.2 MPa, and the end tip pressure was 14.42 MPa. Extrapolation of the pressure records will provide an estimate of the in situ pressure.

Deployment 17: Hole U1322B, 42 mbsf

Table AT38 and FIGUREB23_T2P_DEPLOY17.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 17. When the drill bit was lowered to insert the tool, it recorded temperature and pressure responses. However, the pressure signals decreased significantly when backing-off the drill bit. The pressures were constant during the dissipation phase and were equal to the pressure recorded prior to the tool insertion. The temperature record showed a second spike when backing-off the drill bit and then decayed to a temperature that was close to the borehole fluid temperature. These observations suggest that the tool was communicating with the borehole fluid. Therefore, this deployment did not provide any constraint on in situ conditions.

Deployment 19: Hole U1322B, 134.3 mbsf

Table AT39 and FIGUREB24_T2P_DEPLOY19.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 19. The temperature and pressure records increased while positioning the CDS to the retracted position. When the drill bit was lowered to insert the tool, it recorded further temperature and pressure responses. Pressure and temperature records varied during the penetration process. These variations were due to variations of the sediment properties. The tip and shaft pressures abruptly decreased when the BHA was backing-off the BOH. At the same time, the thermistor recorded a rapid increase. After this perturbation, the tip and shaft pressure rapidly rebounded to nearly constant values. The end shaft pressure was 15.22 MPa, and the end tip pressure was 15.08 MPa. The temperature decayed to an equilibrium temperature of 7.89°C.

Deployment 20: Hole U1322B, 157.8 mbsf

Table AT40 and FIGUREB25_T2P_DEPLOY20.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 20. The temperature and pressure records increased during the first landing attempt with the bit 12 m off BOH, then the tool was pulled back up to reland it with the bit 3 m off the BOH. Fluids were circulated during landing of the tool in the BHA. When the drill bit was lowered to insert the tool, it recorded further temperature and pressure responses. The tip and shaft pressures abruptly decreased when the BHA was backing-off the BOH. At the same time, the thermistor recorded a rapid increase. After this perturbation, the tip pressure rapidly rebounded to a value and then slowly built up to an end pressure of 15.41 MPa. The shaft pressure rapidly rebounded to a nearly constant value of 15.60 MPa. The end pressures may provide a rough estimate of the in situ pressure. The temperature decayed to an equilibrium temperature of 8.47°C.

Deployment 21: Hole U1322C, 50 mbsf

A data acquisition error resulted in only 3 min of recorded data. Inspection of the data acquisition unit after recovering the probe revealed that the memory card was dislodged and thus data could not be recorded. The memory card was replaced, and the quick release button for the card was removed. This modification made it harder for the memory card to be accidentally ejected.

Deployment 22: Hole U1322C, 75 mbsf

This deployment suffered from a hydraulic leak that flooded the electronics connecting the pressure transducers and the thermistor to the data acquisition unit. The flooding shorted all circuits; therefore, no pressure and temperature data were recorded. All electrical components were cleaned and dried after the deployment.

Deployment 23: Hole U1322C, 150 mbsf

Table AT41 and FIGUREB26_T2P_DEPLOY23.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 23. TruView data are only available for the dissipation phase. Temperature and pressure signals increased with landing of the tool in the BHA and again with penetration into the formation. The tip pressure decreased when the bit was pulled up and then slowly rebounded to a final pressure of 15.29 MPa. The shaft pressure decreased when the bit was lifted and then continuously decayed to an end pressure of 15.99 MPa. The temperature decayed to an equilibrium value of 8.26°C.

Deployment 24: Hole U1322C, 200 mbsf

Table AT42 and FIGUREB27_T2P_DEPLOY24.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 24. The tip pressure and temperature records increased while positioning the CDS to the retracted position. A second increase recorded by all sensors occurred when the tool was pushed into the formation. Pressure and temperature records then smoothly dissipated while the tool was in the formation. The tip decayed to a final pressure of 16.34 MPa, and the shaft dissipated to a final pressure of 17.16 MPa. Extrapolation of the pressure records will provide good estimate of the in situ pressure. The temperature decayed to an equilibrium value of 9.28°C.

Deployment 25: Hole U1322D, 40 mbsf

Table AT43 and FIGUREB28_T2P_DEPLOY25.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 25. The TruView data are missing for this deployment. Key deployment events are derived from the shipboard T2P Log Sheet (see the “DOWNHOLE” folder in “Supplementary material”). Pressure and temperature pulses were recorded when the probe was pushed into the formation but the pressure dropped rapidly when the drill bit was lifted off the BOH. The tip and shaft then increased to a nearly constant pressure of 13.78 MPa, which was equal to the fluid pressure at BOH. The temperature decreased rapidly upon pulling up of the bit and then was nearly constant and close to the temperature of the borehole fluid. The pressure and temperature records suggest that the measurement was influenced by communication with the borehole fluid. Thus this deployment did not provide any constraint on in situ conditions.

Deployment 26: Hole U1322D, 70 mbsf

Table AT44 and FIGUREB29_T2P_DEPLOY26.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 26. Similar to Deployment 25, the seal around the probe was weakened when the bit was lifted off the BOH. The pressure and temperature measurements were subject to influence of the borehole fluid. This deployment did not provide any constraint on in situ conditions.

Deployment 27: Hole U1322D, 100 mbsf

Table AT45 and FIGUREB30_T2P_DEPLOY27.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 27. The pressure and temperature records increased while positioning the CDS to the retracted position and pushing the tool into the formation. The tip and shaft pressures rapidly decreased while backing-off the bit. The tip pressure rebounded to a near-constant value of 14.69 MPa. The shaft pressure dissipated to a final value of 15.11 MPa. This dissipation curve can be extrapolated to evaluate the in situ pressure. Smooth temperature decay was measured. The final temperature of 7.11°C was equilibrated with the formation.

Deployment 28: Hole U1322D, 134 mbsf

Table AT46 and FIGUREB31_T2P_DEPLOY28.XLS in the “APP_B” folder in “Supplementary material” present the sequence of the operations and the tool response to particular events for T2P Deployment 28. The pressure and temperature records increased while positioning the CDS to the retracted position and pushing the tool into the formation. The tip and shaft pressures rapidly decreased while backing-off the bit. Pressures at the shaft and tip were near-constant during the dissipation phase. The temperature increased while backing-off the bit and then rapidly decayed to a final temperature of 7.31°C. The pressure and temperature measurements were subject to influence of the borehole fluid. This deployment did not provide any constraint on in situ conditions.

All sensor data records were lost during recovery of the probe. At the rig floor, it was noted that the tip had broken and the drive tube had bent during the deployment. Damage to the probe likely occurred while pushing into the formation and then the tip was broken when pulling out of the formation.

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