Preprints
https://doi.org/10.5194/hess-2022-31
https://doi.org/10.5194/hess-2022-31
 
10 Mar 2022
10 Mar 2022
Status: this discussion paper is a preprint. It has been under review for the journal Hydrology and Earth System Sciences (HESS). The manuscript was not accepted for further review after discussion.

Numerical modeling of physical and biochemical processes in the subsurface and their impacts on the self-potential signature

Xin Liu, Zengyu Zhang, and Alex Furman Xin Liu et al.
  • Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, 32000, Israel

Abstract. Subsurface contamination is a significant problem due to excessive fertigation and industrial and domestic wastewater discharge. With numerical modeling and geophysical tool development, subsurface contaminant research has become easier to implement and study. However, there is still a gap in coupling the biochemical processes and geophysical signals. Such a coupling model is needed to facilitate understanding subsurface processes and provide further theoretical basis to practice and field monitoring. Thus, this research aims to simulate the self-potential (SP) signature in response to physical and biochemical dynamics in the subsurface. For the physico-bio-chemical model, the processes of water flow, solute transport, biochemical reactions, microbial dynamics, adsorption, and gas flow are considered. Specifically, the biochemical cycles related to C, N, Mn, Fe, and S are incorporated in the model. The physico-bio-chemical model is then coupled with the SP model. The SP model is addressed by Poisson’s continuity equation, based on streaming and redox potential contribution. The streaming potential is calculated by the effective excess charge density and the water flow velocity, while the Butler-Volmer equation solves the redox potential. The results show that redox processes dominate the SP signals. Oxygen and nitrate concentrations present positive relationships with redox potential and dominate the redox potential in the oxic and anoxic environment, respectively. Nitrification and dissolved organic carbon (DOC) aerobic oxidation rates show positive relationships with redox potential. In contrast, the denitrification rate presents a negative relationship. The higher reaction rates for different redox processes also correspond to their optimal redox potential ranges. The streaming potential affected by water content and flux contributes little to SP, and the negative values along with soil depth become less remarkable. Generally, the SP and redox potential model can better reflect redox species concentrations and reaction rates, while the streaming potential model can reflect the water content and flux dynamics. Thus, the research can guide the detection of redox-sensitive contamination and water leakage in the subsurface.

Xin Liu et al.

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on hess-2022-31', Andre Revil, 15 Mar 2022
    • AC1: 'Reply on RC1', Xin Liu, 03 May 2022
      • AC2: 'Reply on AC1', Xin Liu, 03 May 2022
    • RC3: 'Reply on RC1', Andre Revil, 03 May 2022
      • EC1: 'Reply to RC3', Gerrit H. de Rooij, 03 May 2022
        • AC6: 'Reply on EC1', Xin Liu, 10 May 2022
      • AC5: 'Reply on RC3', Xin Liu, 10 May 2022
    • AC4: 'Reply on RC1', Xin Liu, 03 May 2022
  • RC2: 'Comment on hess-2022-31', Anonymous Referee #2, 12 Apr 2022
    • AC3: 'Reply on RC2', Xin Liu, 03 May 2022

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on hess-2022-31', Andre Revil, 15 Mar 2022
    • AC1: 'Reply on RC1', Xin Liu, 03 May 2022
      • AC2: 'Reply on AC1', Xin Liu, 03 May 2022
    • RC3: 'Reply on RC1', Andre Revil, 03 May 2022
      • EC1: 'Reply to RC3', Gerrit H. de Rooij, 03 May 2022
        • AC6: 'Reply on EC1', Xin Liu, 10 May 2022
      • AC5: 'Reply on RC3', Xin Liu, 10 May 2022
    • AC4: 'Reply on RC1', Xin Liu, 03 May 2022
  • RC2: 'Comment on hess-2022-31', Anonymous Referee #2, 12 Apr 2022
    • AC3: 'Reply on RC2', Xin Liu, 03 May 2022

Xin Liu et al.

Viewed

Total article views: 641 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
484 131 26 641 41 6 7
  • HTML: 484
  • PDF: 131
  • XML: 26
  • Total: 641
  • Supplement: 41
  • BibTeX: 6
  • EndNote: 7
Views and downloads (calculated since 10 Mar 2022)
Cumulative views and downloads (calculated since 10 Mar 2022)

Viewed (geographical distribution)

Total article views: 603 (including HTML, PDF, and XML) Thereof 603 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 16 Sep 2022
Download
Short summary
This paper built a systematic model to simulate geophysical signals in response to soil physico-bio-chemical dynamics based on the subsurface natural environment. The results show that geophysical signals can better reflect the typical contamination (i.e., C and N) concentration and degradation. Additionally, the signals are also sensitive to water content and flux. Thus, the research can guide the detection of typical contamination and water leakage in the subsurface.