ODP Technical Note 10


Figure I-1. Downhole tools data sheet for WSTP and APC temperature tool. This sheet has been modified during ODP cruise for use with many downhole instruments.

Figure II-1. Block diagram (not to scale) of water-sampling temperature probe (WSTP). Solid lines reveal fluid pathways. 1. pressure case relief valve; 2. upper pressure case bulkhead; 3. sample chamber pressure relief valve; 4. sample overflow chamber; 5. sample coil; 6. sample coil pressure relief check valve; 7. sampling control valve; 8. DC gear motor (SW#1 = motor shut-off and reversing switch, SW#2 = manual motor switch); 9. timer controller; 10. inner case assembly; 11. battery pack (NiCad or Lithium); 12. pressure case (modified core barrel); 13. data logger; 14. high-temperature electrical pass-through (used for high-temperature work only); 15. lower pressure case bulkhead; 16. fluid sampling tubing; 17. drill bit; 18. electrical connection to thermistor; 19. pore-fluid filter and sampling assembly; 20. thermistor housing tip.

Figure II-2. WSTP probe assemblies for temperature measurement only (top) and temperature measurement plus fluid sampling (bottom). All dimensions in centimeters.

Figure II-3. Schematic of Kuster borehole fluid sampler, from operator's manual.

Figure III-1. WSTP downhole deployment schematic, not to scale (Hyndman et al., 1987).

Figure III-2. Performance curves for two typical WSTP thermistors, as configured for high-temperature work during Leg 139. The two circuits allow nominal resolution of 0.1°C over a temperature range of about 0-200°C. The low-temperature thermistor (solid line) reads about 10k ohms at room temperature, while the high-temperature thermistor reads about 100k ohms at room temperature. The upper limit of the data logger is 30k ohms, making the low-temperature thermistor is usable over a temperature range of about 0-70°C, while the high-temperature thermistor is usable over a range of about 60-200°C. Overlap of the two thermistor ranges allows some intercalibration of the two sensors. Both thermistors were calibrated at the factory over their working ranges. Each thermistor is on a separate recorder circuit, with two data independent loggers run in a single recorder frame inside the WSTP. There is plenty of power in a standard WSTP battery pack to support two recorders.

Figure III-3. Ideal records from in-situ sediment temperature stations with the WSTP and APC tool (these data are from APC deployment on Leg 139). The APC tool tends to give smoother, data curves, as this tool has a more stable data logger and penetrates more deeply into the sediments at the bottom of a hole. A. Example record from a complete station in relatively cool sediments. The frictional spike associated with tool insertion is generally greater for the APC tool, which is fired hydraulically into the sediments. B. Example comparing measured and modeled temperature decay from the same run as in (A). Note that the extrapolated final temperature is considerably lower than the lowest value measured while the probe was in the sediments. The shape of the decay curve varies as a function of the thermal properties of the sediments and tool, and the shape of the tool. C. A good temperature vs. time record for a measurement in warm sediments. The frictional heat pulse associated with insertion is barely apparent. D. Example comparing measured and modeled temperature decay from the same run as in (C).

Figure III-4. Photograph of APC tool components (left to right): APC tool on cylindrical holder, APC coring shoe (with internal annular cavity), interface cable attached to another APC tool (turned to show battery packs), interface box, and tool retaining rings (foreground).

Figure III-5. Temperatures measured with the APC tool during Leg 139 in the uncored sediments of "Hole" 395C. The tool was mounted on a core barrel, which was latched in ahead of the bit, then pushed ahead into a sediment pond, pausing periodically to get more stable readings.

Figure III-6. Temperatures measured with the APC tool during DSDP Leg 92 in Hole 504B. The tool was landed at the bit, and sections of pipe were added, one stand at a time, to log a large interval of the open hole.

Figure IV-1. Sketch of the inflatable drill-string packer as deployed during most ODP legs, with a single packer element incorporated into the bottom-hole assembly. A. Packer and drill string before inflation or after deflation. B. Cut-away view of the inflated packer showing go-devil, pressure recorders, and tested interval between the casing shoe and the bottom of the hole. During inflation of the packer, the go-devil directs fluids pumped from the rig floor into the inflation element; once the packer is inflated, a sleeve is shifted such that fluids pumped from the rig floor are directed into the tested formation. Sometimes, two elements are configured as a "single-seal" packer to give the packer assembly greater holding capabilities (for example, against the relatively smooth walls of casing). The ODP straddle packer can also be configured to test an interval between two elements.

Figure IV-2. Anatomy of the rubber elements used on the ODP drill-string packer manufactured by TAM International. The elements of the developmental rotatable packer, wireline packer, and Geoprops probe (none of which is presently functional) had a similar design.

Figure IV-3. The burst pressure of standard drill-string packer elements at various temperatures and inflation diameters. High-temperature elements are also often available on board the JOIDES Resolution.

Figure IV-4. Schematic cutaway drawing of the Kuster K-3 mechanical pressure gauge for use with the drill-string packer.

Figure IV-5. Example of Kuster K-3 gauge record from a packer experiment during Leg 118. This record illustrates the pressure vs. time history of the experiment during one of three packer element inflations in Hole 735B (Becker, 1991). The record shows good responses during both slug and injection testing.

Figure V-1. Schematic illustration of the complete hard-rock (RCB) orientation system, including electronic multishot, swivel, sonic core monitor, and core scriber.

Figure V-2. Cutaway illustration of the scribing core-catcher and SCM target in the RCB coring system.

Figure V-3. Example sonic core monitor records. A. This record reveals almost full recovery, as core height closely follows bit penetration. B. This record reveals incomplete recovery. Recovery stopped when the bit penetrated about 4.5 m, after just 26 minutes of coring. Thus the recovered core came from the upper part of the cored section.

Figure VII-1. Cutaway drawing of the pressure core sampler. A. PCS while cutting ahead. B. PCS with sample chamber closed.

Figure VIII-1. Diagrams of two third-party high-temperature borehole-fluid samplers used during Leg 137. Specifications for these samplers are listed in Table VIII-1. A. LANL borehole sampler. B. LBL fluid sampler.

Figure VIII-2A. Schematic of lateral stress tool, LAST I. This tool is a passive instrument, pushed into the sediments ahead of the bit while collecting a modified piston core.
Figure VIII-2B. Cartoon schematic of LAST II, an active lateral stress tool was run in ODP for the first time during Leg 146. This tool is pressed into the sediments ahead of the bit, where it inflates a membrane and monitors the response of the formation.

Figure VIII-3. Schematic of spinner flowmeter experiment conducted during Leg 139. The dashed lines with arrows illustrate flow paths for fluids pumped from the rig floor, down the pipe, through the inflated packer and go-devil, and into permeable sections of the isolated formation.

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