Skip to main content

Advertisement

Log in

Thermophysical rock properties of the crystalline Gonghe Basin Complex (Northeastern Qinghai–Tibet-Plateau, China) basement rocks

  • Thematic Issue
  • Published:
Environmental Earth Sciences Aims and scope Submit manuscript

Abstract

The basement of the Gonghe Basin complex (GBC) mainly consists of plutonic rocks, which, in general are suitable for geothermal applications. Knowledge of the rock properties of the deep basement formations is of fundamental importance for unconventional geothermal applications such as enhanced geothermal systems. An outcrop analogue study at the margin of the GBC was conducted to improve the understanding of the petrophysical rock properties and enhance the data availability for numeric simulation and resource assessment approaches. In total 148 samples were derived from 21 sampling locations at the margin of the GBC area and mountain ranges within. Lithologically, the sample set was divided in three sample types: (1) syenogranite, (2) granite and biotite granite, (3) granodiorite. Petrophysical properties such as grain density, bulk density, porosity, intrinsic matrix permeability, compressional and shear wave velocities as well as thermal properties like thermal conductivity and thermal diffusivity were analyzed on oven-dry specimens under laboratory conditions (ambient temperature, atmospheric pressure). Unconfined compressive strength was additionally measured on selected samples. The resulting dataset shows averaged bulk densities ranging between 2.59 and 2.73 g cm−3 and porosities from 0.2 to 1.7%. Matrix permeability is lower than 1 × 10–18 m2. Averaged thermal conductivity ranges from 2.34 to 3.19 W m−1 K−1, compressional wave velocity from 3.6 to 6.2 km s−1 and unconfined compressive strength from 128 to 241 MPa. Petrophysical data are correlated with mineral content and grain size to show the influence of petrography on petrophysical properties. Although the petrophysical rock properties were analyzed at laboratory conditions and therefore deviate from in situ properties at reservoir conditions, the presented dataset enhances the knowledge of petrophysical rock properties within the study area for further geothermal applications. A first prediction of in situ reservoir conditions was performed on laboratory data based on empirically determined pressure and temperature dependencies of thermal conductivity, thermal diffusivity, specific heat capacity and compressional wave velocity.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

adapted from Craddock et al. (2014), color code adapted from the International Commission on Stratigraphy at 0.6 opacity

Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

References

Download references

Acknowledgements

The authors thank Hendrik Biewer and Alica De Witt, postgraduate students at Technische Universität Darmstadt for their support in sampling, sample preparation and measuring. Furthermore, the authors thank Qinghai Guo and his whole working group at the China University of Geosciences in Wuhan, especially Xiaobo Zhang, for their dedicated support during the field campaign. This study was partly financed by the DAAD (“Deutscher Akademischer Austauschdienst”) by means of the Federal Ministry of Education and Research. Furthermore, the authors thank for the financial support by the DFG in the framework of the Excellence Initiative, Darmstadt Graduate School of Excellence Energy Science and Engineering (GSC 1070). The authors further thank the reviewers for their thoughtful and helpful comments improving the presented study.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sebastian Weinert.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

This article is a part of the Topical Collection in Environmental Earth Sciences on “Sustainable Utilization of Geosystems” guest edited by Ulf Hünken, Peter Dietrich and Olaf Kolditz.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary file1 (TXT 21 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Weinert, S., Bär, K. & Sass, I. Thermophysical rock properties of the crystalline Gonghe Basin Complex (Northeastern Qinghai–Tibet-Plateau, China) basement rocks. Environ Earth Sci 79, 77 (2020). https://doi.org/10.1007/s12665-020-8808-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s12665-020-8808-9

Keywords

Navigation