Thermal conductivities, thermal diffusivities, and volumetric heat capacities of core samples obtained from the Japan Trench Fast Drilling Project (JFAST)
© Lin et al.; licensee Springer. 2014
Received: 26 February 2014
Accepted: 20 May 2014
Published: 5 June 2014
We report thermal conductivities, thermal diffusivities, and volumetric heat capacities determined by a transient plane heat source method for four whole-round core samples obtained by the Japan Trench Fast Drilling Project/Integrated Ocean Drilling Program Expedition 343. These thermal properties are necessary for the interpretation of a temperature anomaly detected in the vicinity of the plate boundary fault that ruptured during the 2011 Tohoku-Oki earthquake and other thermal processes observed within the Japan Trench Fast Drilling Project temperature observatory. Results of measured thermal conductivities are consistent with those independently measured using a transient line source method and a divided bar technique. Our measurements indicate no significant anisotropy in either thermal conductivity or thermal diffusivity.
KeywordsThermal conductivity Thermal diffusivity Volumetric heat capacity Anisotropy Core sample measurement JFAST
The 2011 Mw 9.0 Tohoku-Oki, Japan, earthquake produced a maximum coseismic slip of >50 m near the Japan Trench in the Miyagi-Oki region, triggering a huge tsunami (Fujiwara et al. 2011; Lay et al. 2011). To understand the reasons for the large displacement of the coseismic slip, the Japan Trench Fast Drilling Project (JFAST, Integrated Ocean Drilling Program (IODP) Expedition 343 and 343T) drilled through the plate boundary fault zone that ruptured during the Tohoku-Oki earthquake. This work was undertaken by the drilling vessel (D/V) Chikyu, approximately 1 year after the earthquake at Site C0019 (Mori et al. 2012; Chester et al. 2012), and one of the principal objectives of JFAST was to detect the residual temperature anomaly induced by the coseismic frictional heat during the earthquake (Fulton et al. 2013).
where C is the volumetric heat capacity. Obtaining measurements of any two of these parameters allows the third to be calculated.
The previous works measuring the physical properties of rocks across the Tohoku-Oki fault zone have focused on thermal conductivity (which is a measure of a material’s ability to transfer heat and has a primary control on the background geothermal gradient) (Expedition 343/343T Scientists 2013b; Fulton et al. 2013). Determination of thermal conductivity in these studies consisted of making 45 line source measurements on split half cores (Expedition 343/343T Scientists 2013b) and 38 measurements made using a divided bar technique on rock chips (Fulton et al. 2013). Details of the divided bar thermal conductivity measurements are given in Sass et al. (1984). These techniques, however, are not suited to measuring thermal diffusivity, a key parameter for understanding the thermal decay associated with frictional heating or other transient disturbances.
In this study, we report both thermal conductivity and thermal diffusivity measurements performed on four whole-round core samples retrieved from the JFAST borehole, using a transient plane heat source method (also known as a hot-disk method). Values of thermal conductivity measured using this technique are then compared to the values previously measured. Relationships between thermal conductivity and thermal diffusivity are also found, and these allow extrapolation of the thermal properties with depth from the more extensively measured thermal conductivity values.
JFAST and core samples
Sample ID, core and section number, depth, and associated basic physical properties
Sample ID: core and section number, depth in the section (cm)
Wet bulk density (g cm−3)
Grain density (g cm−3)
No. 1: 1R-1, 18-34
1, slope facies or wedge sediments
No. 2: 5R-1, 102-117
3, gray mudstone
No. 3: 13R-1, 50-60
3, gray mudstone
No. 4: 19R-2, 73-86
5, brown mudstone
Measurements of thermal conductivity and thermal diffusivity
The thermal constants analyzer TPS 1500 has two measurement modes. The first assumes that the test sample is isotropic and calculates both bulk thermal conductivity and bulk thermal diffusivity. The second mode allows anisotropic measurements and gives values of thermal conductivity and thermal diffusivity in both the radial direction (a horizontal direction in the original position of the core samples) and the axial direction (vertical direction). We obtained measurements using both modes, as discussed below.
The thermal property measurements were conducted at room temperature (at approximately 23°C) and at atmospheric pressure. Using the measurement apparatus referred to above and the environmental conditions specified, the reported measurement precision (reproducibility) for thermal conductivity, thermal diffusivity, and volumetric heat capacity using the bulk mode have been found to be better than 2%, 5%, and 7%, respectively (Hot Disk 2007a). In addition, both precision for thermal conductivity and thermal diffusivity using the anisotropic mode have been found to be 5% (Hot Disk 2007b).
Measurement results using hot-disk method in the four whole-round core samples and fused silica
Ax TC Wm−1K−1
Ax TD 10−7m2s−1
Rad TC Wm−1K−1
Rad TD 10−7m2s−1
1.32 ± 0.00
8.27 ± 0.00
1.60 ± 0.00
1.32 ± 0.01
8.27 ± 0.07
1.33 ± 0.01
8.30 ± 0.07
0.92 ± 0.01
3.16 ± 0.09
2.92 ± 0.09
0.90 ± 0.00
3.16 ± 0.01
0.94 ± 0.00
3.29 ± 0.00
1.14 ± 0.01
3.80 ± 0.04
2.99 ± 0.01
1.11 ± 0.01
3.72 ± 0.04
1.15 ± 0.02
3.84 ± 0.08
1.05 ± 0.01
3.52 ± 0.08
2.99 ± 0.03
1.05 ± 0.02
3.50 ± 0.08
1.03 ± 0.05
3.45 ± 0.16
1.08 ± 0.02
4.43 ± 0.06
2.44 ± 0.04
1.11 ± 0.04
4.61 ± 0.35
1.07 ± 0.03
4.46 ± 0.03
Prior to conducting thermal measurements, the four core samples were used for anelastic strain recovery (ASR) measurements to estimate in situ stress, using a non-destructive onboard measurement (e.g., Lin et al. 2006). To prepare our samples for measuring, they were saturated in water that had roughly the same NaCl solution concentration as sea water, for a period of approximately 24 h. The core samples were then cut into two pieces perpendicular to the core axis and the thin hot disk was sandwiched between them. The sample size used had a diameter of approximately 56 mm, (about four times the diameter of the heating plate), and each sample had a thickness of >20 mm. Based on a time window of 20 s and measured thermal diffusivities of approximately 5 × 10−7 m2s−1, a thermal length of about 6 mm was obtained, which confirmed that our sample size was sufficiently large enough to approximate a half space.
Measurement results and discussion
The thermal conductivity values found in our study are consistent with the values of 45 measurements made onboard, which were conducted on split cores using a TeKa thermal conductivity half-space probe (TeKa Thermophysical Instruments - Geothermal Investigation, Berlin Germany; Expedition 343/343T Scientists 2013c), and of 38 discrete samples were measured using a divided bar system (Fulton et al. 2013) (Figure 4A). However, a significantly higher thermal conductivity value (approximately 1.6 Wm−1K−1) was measured using the line heat source method for a chert core sample obtained from approximately 837 mbsf in lithologic unit 7 (Figure 4A).
The thermal diffusivity bulk measurements on the four core samples varied between 3.2 and 4.4 × 10−7 m2s−1, and some variations are greater than the reported measurement precision of different samples (Table 2 and Figure 4B). The thermal diffusivity at the shallowest depth of approximately 177 mbsf in lithologic unit 1 (slope facies or wedge sediments) is lower, and largely reflects the influence of lower thermal conductivity therein. The other three thermal diffusivity values were determined on mudstone samples taken from 697 to 828 mbsf. These samples are considered likely to be representative of many of the depth intervals that were monitored using closely spaced temperature sensors in the adjacent observatory borehole (Fulton et al. 2013). The average thermal diffusivity for these three samples was found to be 3.92 ± 0.5 × 10−7 m2s−1. Inverse modeling of the frictional heat signal observed in the JFAST observatory utilized this same range of diffusivities to estimate the amount of heat energy dissipated at this location during the earthquake (Fulton et al. 2013).
The volumetric heat capacity of the four samples showed similar values for the upper three core samples but a significantly lower value for the deepest core sample (Table 2 and Figure 4C). The deepest core sample within lithologic unit 5 (brown mudstone) consists mainly of subducting pelagic clays and clearly shows a lower grain density, suggesting a different solid composition, for example, more clay minerals and volcaniclastic grains. It is considered that the lower volumetric heat capacity and higher thermal diffusivity of the deepest core sample could be attributed to these differences. The average and standard deviation of the three deepest samples is 2.80 ± 0.32 MJm−3K−1, and this range of values was used in the inversion of the analysis of the JFAST observatory frictional heat anomaly (Fulton et al. 2013).
Very slight differences were seen between the anisotropic measurements of thermal conductivity and thermal diffusivity in both the axial and radial directions. The maximum difference of the average values of thermal conductivity in both directions was 0.04 Wm−1K−1, corresponding to approximately 4% of their thermal conductivity values of approximately 1 Wm−1K−1 for the no. 2 sample. These values are less than the 5% level of measurement precision in the anisotropic measurement mode. In addition, the differences between thermal diffusivity in the two directions were similar. In theory, the anisotropic features of thermal diffusivity should be similar to those of thermal conductivity because the volumetric heat capacity is a scalar. It is therefore considered that anisotropy of no more than 5% exists in the thermal conductivity and thermal diffusivity of the four JFAST core samples.
Measured results of thermal conductivities and estimated values of thermal diffusivities and volumetric heat capacities
Depth interval of the unit (mbsf)
Depth interval of samples in the unit (mbsf)
Number of data
Bulk measurement values (TC) and predicted values (TD and VHC)b
0.94 ± 0.09
3.02 ± 0.46
3.15 ± 0.21
1.18 ± 0.10
4.10 ± 0.54
2.89 ± 0.14
1.16 ± 0.08
3.99 ± 0.40
2.91 ± 0.10
1.16 ± 0.09
4.01 ± 0.48
2.91 ± 0.12
1.14 ± 0.06
3.99 ± 0.31
2.88 ± 0.15
1.08 ± 0.06
3.60 ± 0.32
3.01 ± 0.09
1.40 ± 0.17
5.29 ± 0.89
2.67 ± 0.16
Estimation of thermal diffusivity using thermal conductivity at JFAST site
Correlation between thermal conductivity and thermal diffusivity
(for sand by Goto and Matsubayashi 2008)
Estimation of thermal diffusivity
We determined thermal conductivities, thermal diffusivities, and volumetric heat capacities using a transient plane heat source method at atmospheric pressure, in room-temperature conditions, and in a fully saturated state. The four whole-round core samples used were obtained as part of the Japan Trench Fast Drilling Project (JFAST), with the primary objective of interpreting the frictional heat signal from slip during the 2011 (Mw 9.0) Tohoku-Oki earthquake in terms of coseismic friction (Fulton et al. 2013). Characterization of all three thermal properties is important for properly interpreting the detected temperature anomaly in the vicinity of the plate boundary fault and for the analysis of other thermal processes observed within the JFAST observatory temperature data. The measured thermal conductivities were found to be consistent with those independently measured using a transient line source method for 45 half-core samples in an onboard laboratory and using a divided bar technique on 38 rock-chips samples in a shore-based laboratory. We examined several previously proposed empirical equations describing relationships between thermal diffusivity and thermal conductivity for ocean sediments, by applying our data obtained from using the transient plane heat source method. We then used these results to estimate the thermal diffusivities and the volumetric heat capacities of the 45 half-core samples and 38 rock-chips samples by their thermal conductivities, covering the whole-cored depth range of the JFAST borehole. Our measurements reveal less than 5% anisotropy in terms of thermal conductivity and thermal diffusivity (the detectable limit of the measurement apparatus). The extrapolations suggest little variation in any of the three thermal properties within several tens of meters above the plate boundary fault (where a 0.31°C temperature anomaly has been observed). The parameters used to model and interpret this signal in terms of coseismic frictional heating utilized the measurement values presented here. Our extrapolation of thermal diffusivity and volumetric heat capacity from empirical relationships with thermal conductivity suggests that the range of values used in the modeling are reasonable, as is the assumed general uniformity of values within the mudstones from approximately 800 to 820 mbsf.
Characterization of the three thermal properties and their possible variation with depth provides important constraints for further investigations of other thermal processes observed within the JFAST temperature observatory. For example, Fulton et al. (2013) reported that the characteristic recovery time of the drilling disturbance within the JFAST temperature data is spatially variable, with larger recovery times at around 765, 800, and 810 mbsf. These regions were thus interpreted as permeable zones with a greater infiltration of drilling fluids. Although further analysis is warranted and ongoing, our depth profiles of thermal properties reveal no large spatial variations that would obviously account for these observations, suggesting instead that they may indeed be influenced by the hydrogeologic structure.
The JFAST temperature data has provided a remarkable window into the subsurface thermal field across the plate boundary fault, at a time period of 16 to 25 months after the 2011 Mw 9.0 Tohoku-Oki earthquake. It is considered that characterization of the thermal property structure within the subsurface provides a context for further investigations into the hydrologic and thermal signals observed within the JFAST temperature data and the constraints on models of frictional heating and other thermal processes within the shallow subduction zone.
The core samples used in this study were provided by IODP expedition 343. The authors gratefully acknowledge the support provided by the Expedition 343/343T Scientists, D/V Chikyu drilling crew, and laboratory technicians. Part of this work was supported by Grants-in-Aid for Scientific Research 21107006 (MEXT) and 25287134 (JSPS), Japan. PF was supported by the US Science Support Program of IODP and the Gordon and Betty Moore Foundation.
- Argus DF, Gordon RG, DeMets C: Geologically current motion of 56 plates relative to the no-net-rotation reference frame. Geochem Geophys Geosyst 2011., 12: Q11001 doi:10.1029/2011GC003751Google Scholar
- Bullard EC: The heat flow of heat through the floor of the Atlantic Ocean. In Proceedings of Royal Society, vol A, 222. London: Royal Society; 1954:408–429. doi:10.1098/rspa.1954.0085Google Scholar
- Chester FM, Mori JJ, Toczko S, Eguchi N, Expedition 343/343T Scientists: Integrated ocean drilling program expedition 343/343T preliminary report. Japan Trench Fast Drilling Project (JFAST). 2012. doi:10.2204/iodp.pr.343343T.2012Google Scholar
- Chester FM, Rowe C, Ujiie K, Kirkpatrick J, Regalla C, Remitti F, Moore JC, Toy V, Wolfson-Schwehr M, Bose S, Kameda J, Mori JJ, Brodsky EE, Eguchi N, Toczko S, Expedition 343 and 343T Scientists: Structure and composition of the plate-boundary slip zone for the 2011 Tohoku-Oki earthquake. Science 2013, 342: 1208–1211. doi:10.1126/science.1243719View ArticleGoogle Scholar
- Expedition 343/343T Scientists: Expedition 343/343T summary. In Proceedings of the IODP, vol 343/343T. Edited by: Expedition 343/343T Scientists, Chester FM, Mori J, Eguchi N, Toczko S. Tokyo: Integrated Ocean Drilling Program Management International, Inc; 2013a. doi:10.2204/iodp.proc.343343T.101.2013Google Scholar
- Expedition 343/343T Scientists: Methods. In Proceedings of the IODP, vol. 343/343T. Edited by: Expedition 343/343T Scientists, Chester FM, Mori J, Eguchi N, Toczko S. Tokyo: Integrated Ocean Drilling Program Management International, Inc; 2013b. doi:10.2204/iodp.proc.343343T.102.2013Google Scholar
- Expedition 343/343T Scientists: Site C0019. In Proceedings of the IODP, vol. 343/343T. Edited by: Expedition 343/343T Scientists, Chester FM, Mori J, Eguchi N, Toczko S. Tokyo: Integrated Ocean Drilling Program Management International, Inc; 2013c. doi:10.2204/iodp.proc.343343T.103.2013Google Scholar
- Fujiwara T, Kodaira S, No T, Kaiho Y, Takahashi N, Kaneda Y: The 2011 Tohoku-Oki earthquake: displacement reaching the trench axis. Science 2011, 334: 1240. doi:10.1126/science.1211554View ArticleGoogle Scholar
- Fulton PM, Brodsky EE, Kano Y, Mori J, Chester F, Ishikawa T, Harris RN, Lin W, Eguchi N, Toczko S, Expedition 343, 343T, and KR13–08 Scientists: Low coseismic friction on the Tohoku-Oki fault determined from temperature measurements. Science 2013, 342: 1214–1217. doi:10.1126/science.1243641View ArticleGoogle Scholar
- Goto S, Matsubayashi O: Inversion of needle-probe data for sediment thermal properties of the eastern flank of the Juan de Fuca Ridge. J Geophys Res 2008., 113: B08105 doi:10.1029/2007JB005119Google Scholar
- Gustafsson SE: Transient plane source techniques for thermal conductivity and thermal diffusivity measurements of solid materials. Rev Sci Instrum 1991, 62: 797–804. 10.1063/1.1142087View ArticleGoogle Scholar
- Horai K, Simons G: Thermal conductivity of rock-forming minerals, Earth Planet Sci. Lett 1969, 6: 359–368.Google Scholar
- Horai K, Susaki J: The effect of pressure on the thermal conductivity of silicate rocks up to 12 kbar. Phy Earth Planetary Inter 1989, 55: 292–305. 10.1016/0031-9201(89)90077-0View ArticleGoogle Scholar
- Hot Disk: Instruction manual, hot disk thermal constants analyser–Software Version 5.9. p 42. Hot Disk Inc., Gothenburg, Sweden; 2007a.Google Scholar
- Hot Disk: Instruction manual, anisotropic application, hot disk thermal constants analyser–software version 5.9. 42. Hot Disk Inc, Gothenburg, Sweden; 2007b.Google Scholar
- Hyndman RD, Davis EE, Wright JA: The measurement of marine geothermal heat flow by a multipenetration probe with digital acoustic telemetry and in situ thermal conductivity. Mar Geophys Res 1979, 4: 181–205. doi:10.1007/BF00286404View ArticleGoogle Scholar
- ISO: Plastics–determination of thermal conductivity and thermal diffusivity–part 2: transient plane heat source (hot disc) method, International Standard ISO 22007–2. International Organization for Standardization, Geneva, Switzerland; 2008.Google Scholar
- Kaye GWC, Laby TH: Tables of physical and chemical constants and some mathematical functions. 15th edition. Longman, London; 1986:477.Google Scholar
- Lay T, Ammon CJ, Kanamori H, Xue L, Kim MJ: Possible large near-trench slip during the 2011 Mw 9.0 off the Pacific coast of Tohoku earthquake. Earth Planets Space 2011, 63: 687–692. doi:10.5047/eps.2011.05.033View ArticleGoogle Scholar
- Lin W, Kwasniewski M, Imamura T, Matsuki K: Determination of three-dimensional in-situ stresses from anelastic strain recovery measurement of cores at great depth. Tectonophysics 2006, 426: 221–228. 10.1016/j.tecto.2006.02.019View ArticleGoogle Scholar
- Lin W, Tadai O, Hirose T, Tanikawa W, Takahashi M, Mukoyoshi H, Kinoshita M: Thermal conductivities under high pressure in core samples from IODP NanTroSEIZE drilling site C0001. Geochem Geophys Geosyst 2011, 12: Q0AD14. doi:10.1029/2010GC003449View ArticleGoogle Scholar
- Lin W, Conin M, Moore JC, Chester FM, Nakamura Y, Mori JJ, Anderson L, Brodsky EE, Eguchi H, Expedition 343 Scientists: Stress state in the largest displacement area of the 2011 Tohoku-Oki earthquake. Science 2013, 339: 687–690. doi:10.1126/science.1229379View ArticleGoogle Scholar
- Mori JJ, Chester FM, Eguchi N, Toczko S: Japan Trench Fast Earthquake Drilling Project (JFAST). IODP expedition 343 scientific prospectus. 2012. doi:10.2204/iodp.sp.343.2012, 343Google Scholar
- Ratcliffe EH: The thermal conductivities of ocean sediments. J Geophys Res 1960, 65: 1535–1541. doi:10.1029/JZ065i005p01535View ArticleGoogle Scholar
- Sass JH, Stone C, Munroe RJ: Thermal conductivity determinations on solid rock—a comparison between a steady-state divided bar apparatus and a commercial transient line-source device. Jour Volcanol Geotherm Res 1984, 20: 145–153. 10.1016/0377-0273(84)90071-4View ArticleGoogle Scholar
- Von Herzen RP, Maxwell AE: The measurement of thermal conductivity of deep-sea sediments by a needle-probe method. J Geophys Res 1959, 64: 1557–1563. doi:10.1029/JZ064i010p01557View ArticleGoogle Scholar
- Yang T, Mishima T, Ujiie K, Chester FM, Mori JJ, Eguchi N, Toczko S, Expedition 343 Scientists: Strain decoupling across the décollement in the region of large slip during the 2011 Tohoku-Oki earthquake from anisotropy of magnetic susceptibility. Earth Planet Sci Lett 2013, 381: 31–38. dx.doi.org/10.1016/j.epsl.2013.08.045View ArticleGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.