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Table of Contents
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I. Introduction

Thermal conductivity is the coefficient of proportionality relating conductive heat flow to a thermal gradient. The Teka Berlin TK04 system

Table of Contents
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I. Introduction


Thermal conductivity is the coefficient of proportionality relating conductive heat flow to a thermal gradient. The Teka Berlin TK04 system determines thermal conductivity based on a transient heat flow method. A line source is heated with constant power while recording source temperature. Thermal conductivity is calculated from the resulting heating curve.
The TK04 uses two types of probes: the full-space (VLQ) needle probe for soft sediments and the half-space (HLQ) probe for hard rock samples. Measuring a single point in a section takes ~54 min per sample, allowing for 3 replicates to be taken. A self-test including a drift study is conducted at the beginning of each cycle. To measure thermal conductivity the heater circuit is closed and the temperature rise in the probe is recorded. Thermal conductivity is calculated from the rate of temperature rise while the heater current is flowing. The thermal conductivity of each sample is the average of three repeated measurements for the full-space method and three to six repeated measurements for the half-space method.
Precision of the method is better than 2%, based on extended evaluation of the method; accuracy is about 5% because of random variations of thermal conductivity in natural materials.

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Process

Time (min)

Comments

1. Obtain a whole-round core section from the core rack

0.3

See Preparing Sections & Samples for Analysis


2. Locate the appropriate probe for the sample type

0.5

3. Verify sample identification in software

0.5

See Configuring Set Measurement ProgramParameters


4. Configure measurement program

0.3

5. Perform drift control

5

See Measuring Samples Making a Measurement




6. Heat and measure sample

2

7. 10 minute pause between measurements

10

8. Repeat steps 5-7 for 2 additional measurements (3 total)

34

9. Upload results to LIMS

0.2

See Uploading Data to LIMS and Verifying Data in LIMS



10. Check results in LIMS

1

11. Remove the section and deliver to splitting room

0.2

Total Time per sample:

54 (max)


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A. Preparing the Instrument

B. Instrument Calibration 

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  1. Double-click the ThermCON icon on the desktop (Figure 1) and login using ship credentials. ThermCON window will pop-up. Sample data will be added in this window.

  2. Double-click the TK04 icon (Figure 1). TK04 window will open. Measurement parameters will be added in this window.


Image Added

Figure 1. ThermCON Icon (left). TK04 Icon (right).

B. Instrument Calibration 


The TK04 doesn't need to be calibrated. In order to verify that taken measurements are in the correct range of values, MACOR standards are measured at the start of each expedition.

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C. Set Measurement Parameters

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  1. Load ThermCon software in offline mode. Ensure that the Text_ID field is blank.
  2. Scan the core label using a scanner, then click Verify Sample.
  3. If login is requested, enter UserName and Password and then click OK.
  4. The folder path is shown on the screen. Do not close this window during measurement. 
  5. Run TK04 program and choose Measuring > Configuration
  6. Set configuration parameters as follows (see figure below):
    1. Probe Number: serial number of probe to be used in the measurement (Note: results may be wrong by several percent if the wrong serial number is entered or by a factor of ~2 if the wrong type of probe is entered),
    2. Root Name: six characters or less; suggest Core-Type-Section (no special characters in the root name).
    3. Serial Number: number of repeat measurements at each measurement point (1–99 single measurements).
    4. Folder: path for saving data results.
    5. Heating Power: for the VLQ (needle probe), set to twice the estimated thermal conductivity value of measured sediment. For example, 2–3 is good for sediment. (See the Appendix: TK04 Recommended Heating Power for power guidance.)
    6. Measuring Time: set to at least 80 s, or for mini HLQ 60 s.
    7. Click Expert Options to configure Drift Control and Pause in Minutes (see Step 7).
    8. Enter comments.

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  1. Equilibrate core sections to room temperature for at least 4 hours in the core rack before bringing a target section to the thermal conductivity workstation.
  2. Select measuring points in the core
    1. Intact core: middle of section; record offset in cm
    2. Cracked core: just above/below the middle (but in any case away from the crack); record offset in cm
  3. Use the cordless drill to drill a ~2 mm hole into the core liner at the borderline between working and archive halves. If the sediment is unconsolidated, drill only through the core liner. If the sediment is semiconsolidated, drill a small hole in the sediment for the probe as well.
    Caution: it is very easy to bend the needle on the VLQ full space needles!
  4. Optional - Apply thermal joint compound to the probe unless the sample is very soft and/or moist.
  5. Carefully insert a clean full-space needle into the sediment. Avoid twisting the needle into the core. The needle must be completely inserted into the sample up to the handle. Do not attempt to force the needle into the sample if the resistance is too great; DO NOT BEND THE NEEDLE.


Figure 12. Thermal conductivity measurement on a soft-sediment section using full-space probe.

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  1. Confirm configuration settings shown in the lower part of the TK04 screen, insert the probe into the hole drilled into the sample, and click Start Measuring. 
  2. Drift control (DCL) repeats until the criterion for drift (set in the Expert Options window) is met. Each drift control measurement takes 0.5 min. For DCL = 40, drift control is <10 series (~5 min). For DCL = 10, drift control is <30 (~15 min).
    1. Counter: remaining number of measurements in the current drift series
    2. Recording: currently recorded time and temperature and drift series being recorded
    3. Drift: drift value from the last drift series; indicated in blue on the slider scale when acceptable
    4. Start signal light:
      1. Yellow: drift has reached the threshold; approximately half the drift time has passed
      2. Green: drift limit has been reached and measurement can begin
  3. After satisfying drift control, sample heating and measuring begins, and temperature values are corrected automatically for the drift effect predicted from the last drift series. Elapsed measurement time is controlled by the value entered in Configuring Measurement Program > Step 6F.
    1. Recording: displays currently recorded time and temperature
    2. Data: lists recorded time/temperature values from the heating curve
    3. Heating diagram: continuously updated; can display as linear or logarithmic scale
  4. Solutions calculated by the algorithm are shown on the screen. Note the result on the handwritten log.
    1. TC: thermal conductivity
    2. LET: logarithm of the extreme time (lower limit = 4); the measurement with the largest LET is used to calculate thermal conductivity
    3. CV: contact value
    4. PC: power control is shown on the plot in the lower part of the screen (recommended PC = 2–3. If PC is out of range, adjust the Heating Power (HP) in Configuring Measurement Program > Step 6E as follows: if PC > 3, decrease HP; if PC < 2, increase HP).
    5. Mean: mean thermal conductivity
    6. Count: number of measurements used to calculate thermal conductivity

F. Evaluating your Measurement

G. IMS Utilities

III. Uploading Data to LIMS

A. Data Upload Procedure

  1. To upload results to LIMS, click Upload to LIMS. If upload is successful, a message like "Logged results for sample …" is shown. Close the ThermCon program. Image Removed

B. View and Verify Data

Verifying Data in LIVE (LIMS Viewer)

Run LIVE from the ship application page to check thermal conductivity data:

  1. Select the PHYS_PROPS_Summary template.
  2. Select the Site/Hole/Interval to be queried.
  3. Click View Data.

Retrieving Data from LIMS REPORTs

  1. Go to LIMS Reports at http://webserv.ship.iodp.tamu.edu:8080/UWQ/.
  2. Under Select Report, choose Physical Properties > Thermal Conductivity (TCON).

Note: The "expanded" report shows all of the database parameters and may be confusing to a general user; use the "standard" report.

3. Under Select Sample Range, specify Expedition, Site, Hole, and Section image(s) to retrieve.

4. Click View data or Download data file to view results or download a CSV file.

After Verifying Data Upload

  1. Once uploaded data are confirmed, clean the needle probe and place it in its styrofoam storage container.
  2. Repeat sample measurement process with a new sample.

Data Management

Once all sections for the Expedition have been sent through the track, all data needs to be placed in the appropriate folders on data1 (S:\data1).
1. Copy files from archive and place them in the 5.1 Petrophysics TCON thermcon folder. Confirm relocation. Delete all files off the local drive.

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5. Upload data to LIMS and review if they appear on the data base (See next section).

Note: The "expanded" report shows all of the database parameters and may be confusing to a general user; use the "standard" report.

6. Once uploaded data are confirmed, clean the needle probe and place it in its styrofoam storage container.

7. Repeat sample measurement process with a new sample.



III. Uploading Data to LIMS


A. Data Upload Procedure


  1. To upload results to LIMS, click Upload to LIMS. If upload is successful, a message like "Logged results for sample …" is shown. Close the ThermCon program. Image Added


B. View and Verify Data

Data Available in LIVE

The data measured on each instrument can be viewed in real time on the LIMS information viewer (LIVE).

Choose the appropriate template (Ex: PHYS_PROPS_Summary), Expedition, Site, Hole or the needed restrictions and click View Data. The requested data will be displayed. You can travel in them by clicking on each of each core or section, which will enlarge the image.


Data Available in LORE

Each data set from the Thermoconductivity Station is written to a file by section. These reports are found under the Physical Properties heading. The expanded reports include the linked original data files and more detailed information regarding the measurement.



Analysis

Component

Unit

Definition

TCON

Bottom_depth

m

Location of bottom of measurement, measured from the top of the hole

Comment

None

Comment about the run

Contact_value

None

Measure of contact quality between probe and sample

End_time

s

Elapsed time for end of analysis window

Heating_power

W/m

Power applied to needle during heating

Length_of_time

s

Elapsed time, start to finish, of analysis

Log_extreme_time

s

LET, used in calculation algorithm

Method

None

Data reduction method: SAM or TCON

Needle_name

None

Full-space or half-space

Number_of_solutions

None

Number of solutions found by the software

Offset

cm

Location of measurement from top of section

Start_time

s

Elapsed time into experiment for start of analysis window

Therm_con_average

W/(m·K)

Mean thermal conductivity result

Therm_con_number

None

Number of measurements in the population

Therm_con_result

W/(m·K)

Individual thermal conductivity result

Therm_con_stdev

W/(m·K)

Standard deviation (n-1) of measurement population

Top_depth

m

Location of top of measurement from top of hole

C. Retrieve Data from LIMS

IV. Important Notes

V. Appendix

A.1 Health, Safety & Environment

Safety

...

Expedition data can be downloaded from the database using the instrument Expanded Report on Download LIMS core data (LORE).



IV. Appendix


A.1 Health, Safety & Environment


Safety

This analytical system does not require personal protective equipment.


Pollution Prevention

This procedure does not generate heat or gases and requires no containment equipment.

A.2 Maintenance and Troubleshooting


Troubleshooting


Drift phase takes too long:

  • Ambient temperature is not stable: allow sample more time to equilibrate
  • Probe and sample are not in equilibrium with ambient temperature: place sample/probe in insulated case
  • If necessary, force measurements by choosing a weaker drift limit


Variation of measurement series is too high:

  • Ambient temperature is not stable enough
  • Heating power too low to produce sufficient temperature increase: increase heating power
  • Start time maximum value is too high: set to 40 s
  • Interval length minimum value is too low: set to >25–30 s
  • Contact values vary strongly: omit outliers from evaluation


Evaluation returns few or no solutions:

  • Wet sample may cause convection effects: reduce heating power
  • Poor contact between probe and sample: use contact fluid
  • Interval length minimum value too high: set <30 s
  • Start time maximum value too low: set to 40 s
  • Variations in ambient temperature: insulate sample and/or probe
  • Heat transport into the sample is not distributed: smooth sample surface and apply contact fluid
  • Issue with the probe: Run test on Macor Standard to see if you get expected results


LET values too low:

  • Poor contact between probe and sample
  • Unstable ambient temperature
  • Interval length or start time minimum values too high


Evaluation intervals start later than ~35 s:

  • Poor contact between probe and sample
  • Heating power too high
  • Boundary effects caused by finite probe length

Descending trend in thermal conductivity values:

  • Water-saturated samples drying out: keep sample wet during analysis

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Material


Thermal Conductivity (W/m·K)


Recommended Heating Power (W/m)


Mean

Range

VLQ

HLQ

Wood

0.21

0.1–0.35

0.15–1.3

Coal

0.29

0.1–1.5

0.15–5.4

Concrete

1.00

0.75–1.4

1.0–5.0

0.5–2.2

Fused silica

1.40

1.33–1.46

1.8–5.2

0.8–2.3

Clay

1.40

1.2–1.7

1.6–6.1

0.7–2.6

Silt

1.60

1.4–2.1

1.9–7.5

0.8–3.2

Basalt

1.95

1.4–5.4

1.9–19.0

0.8–7.6

Siltstone

2.04

0.6–4.0

0.8–14.0

0.4–5.7

Limestone

2.29

0.5–4.4

0.7–16.0

0.4–6.3

Syenite

2.31

1.3–5.3

1.7–19.0

0.8–7.5

Amphibolite

2.46

1.4–3.9

1.9–14.0

0.8–5.6

Claystone

2.46

1.6–3.4

2.1–12.0

0.5–9.3

Lava

2.47

0.2–4.5

0.3–16.0

0.2–6.4

Gabbro

2.50

1.6–4.1

2.1–15.0

0.9–5.9

Dolerite (Diabase)

2.64

1.6–4.4

2.1–16.0

0.5–6.3

Granodiorite

2.65

1.3–3.5

1.7–13.0

0.8–5.0

Quartz sand (wet)

2.70

2.4–3.1

3.2–11.0

1.3–4.5

Marble

2.80

2.1–3.5

1.8–13.0

1.2–5.0

Porphyrite

2.82


3.8–10.0

1.5–4.2

Boulder clay

2.90

2.5–3.3

3.4–12.0

1.4–4.8

Diorite

2.91

1.7–4.2

2.3–15.0

1.0–6.0

Slate (perpendicular)

2.91

1.5–3.9

2.0–14.0

0.9–5.6

Gneiss

2.95

1.2–4.7

1.6–17.0

0.7–6.7

Granite

3.05

1.2–4.5

1.6–16.0

0.7–6.4

Eclogite

3.10

2.4–3.4

3.2–12.0

1.3–4.9

Andesite

3.20

1.6–4.7

2.1–17.0

1.0–6.7

Dolomite

3.62

1.6–6.6

2.1–20.0

1.0–9.3

Slate (parallel)

3.80

2.2–5.2

3.0–19.0

1.2–7.4

Peridotite

3.81


5.0–14.0

2.0–5.5

Anhydrite

4.05

1.0–6.0

1.3–20.0

0.6–8.5

Pyroxenite

4.27

3.2–5.1

4.3–18.0

1.7–7.2

Dunite

4.41

3.5–5.2

4.7–19.0

1.9–7.4

Quartzite

4.55

3.1–>8

4.2–20.0

1.7–11.0

Quartz

9.50

6.5–12.5

8.7–20.0

3.5–17.0

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V. Credits


This document originated from 2009, TK04 UG v.,V378P | 372 (Revised: 372|V371T|no change 03/18  ), that had contributions from the authors Hastedt, Y.-G. Kim, M.A. Kominz, and the reviewers David Houpt, T. Gorgas, M. Vasilyev, R. Wilkens, K. Milliken, H. Barnes, S. Hermann; T. Cobb. Credits for subsequent changes to this document are given in the page history.

All improvements to the Quick Start Guides and User Guides are a communal effort, with honorable mention to the group of LOs, ALOs, and technicians who have helped.

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VI. Archived Versions