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Table of Contents
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A simple way of calculating the thermal conductivity coefficient k is picking temperatures T1 and T2 at times t1 and t2, respectively, from the temperature vs. times measurement curve:

ka(t) = q/4p[ln(t2) – ln(t1)]/(T2T1).

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All probes consist of a source (i.e., a metal needle with an embedded heating wire and a temperature sensor), a handle or body (depending on the probe type), and a connection cable.
Full-space probes (VLQ) are needle probes equipped with a handle at one end of the source. They are completely inserted into the sample.
Half-space probes (HLQ), or "Pucks", are placed on top of the sample. The source is embedded into the bottom side of a puck-like probe body and has on-site contact with the material/sample.

Name

Standard VLQ

Standard HLQ

Mini HLQ

Probe type:

Full-space

Half-space

Half-space

Dimension (source, mm):

L: 70 × diameter (D): 2

L: 70 × D: 2

L: 45 × D: 1.5

Dimension (handle/body, mm):

L: 90 × D: 16

L: 30 × D: 88

L: 30 × D: 50

Evaluation parameter set:

Standard VLQ (VLQ Source 70x2)

Standard HLQ (HLQ D88 Source 70x2)

Mini HLQ (HLQ D50 Source 45x1.5)

Measuring range (W/m·K):

0.1–10

0.3–10

0.3–3

Accuracy (%):

±2

±2

±5

Duration of 1 measurement (s):

80

80

60

Min. sample size (mm):

L: 75 × D: 30

L: 15 × D: 80

L: ~15 × D: 50

Picture:

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Analytical process


The approximate amount of time needed per sample is as follows:

Process

Time (min)

Comments

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

0.3

See Preparing Sections & Samples


2. Locate the appropriate probe for the sample type

0.5

3. Verify sample identification in software

0.5

See Set Measurement Parameters


4. Configure measurement program

0.3

5. Perform drift control

5

See 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



10. Check results in LIMS

1

11. Remove the section and deliver to splitting room

0.2

Total Time per sample:

54 (max)


II. Procedures


A. Preparing the Instrument

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  1. Prior to initial testing of received cores at a site, the TK04 system should be tested and calibrated to ensure that there are no potential mechanical or software issues. Additional tests using the Standards should be run as part of the troubleshooting process if you experience issues during actual testing (See Troubleshooting).
  2. The Macor Standard for the Standard VLQ consists of its black holding shell, while the Macor Standard for both the Standard HLQ and Mini HLQ is a white disc. Calibration tests for any of the available probe types should provide results of TC=1.626-1.637±2%. The Macor standard drift calculations are based on a Macor standard (1.637 ± 0.033 W/mK) because its properties are closest to basalt cores (See Appendix: TK04 Recommended Heating Power for information).

    Standard VLQ- MACOR Standard

    Standard MACOR Disc

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    Probe Test TC Value Expected Results:
    TC= 1.626±2% W/mK

    Probe Test TC Value Expected Results:
    TC= 1.637±2% W/mK


  3. To conduct a probe test, scan the STND MACOR disc TCON (H) label kept above the testing apparatus and ensure that the appropriate heating time and drift control (DCL) settings are input under the Configuration settings (See Configuring the Measurement Program).

    Example 1: A Standard HLQ properly positioned on the Standard MACOR Disc.

    Image Modified


  4. Once the proper settings are confirmed, you can test the probes on the standard as if it were a normal sample. For the Standard VLQ this consists of leaving the probe needle in the MACOR standard, while for the HLQ probes you will need to attach it to the Standard MACOR Disc with a rubber band (See Example 1).

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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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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

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Note: for loose sediments, use a lower heating power to avoid convective heat transport of pore fluids.


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


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.

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