Bio


I am a research geophysicist working in the Environmental Geophysics group at the Department of Geophysics, Stanford University. My research activities in the field of Near Surface Geophysics have focused on the development and application of geophysical methods for subsurface imaging. Specifically, I have been working on the development and application of electromagnetic (EM) methods including time-domain EM, TEM (airborne, ground-based, towed) and nuclear magnetic resonance, NMR (Surface/ Borehole/Laboratory).

I have worked on subsurface characterizations using airborne-EM geophysics for large-scale mapping, surface geophysics for site characterizations, tow-TEM for high-resolution 3D imaging of the subsurface as well as logging and laboratory experiments. Most of my research activities have aimed to efficiently map and analyze groundwater systems. I have worked in different international research projects and have conducted numerous geophysical field campaigns worldwide and analyzed different airborne, ground-based, logging and laboratory data.

In California, I have been working on aquifer characterization in the Indian Wells Valley to assess fresh and brackish portions of this geologically complex groundwater system. This project aims to develop a template for an optimal workflow that would use airborne EM data as the foundation for the development of hydrogeologic conceptual models. Moreover, I led a research project recently in Tulare, CA to evaluate potential recharge basins as well as the suitability of on-farm recharge sites using a recently developed towed TEM system that is specifically designed for 3-D high-resolution imaging of the upper 50-80 m of the subsurface.

My research in the field of NMR has focused recently on integration of the NMR data at multiple scales and also on determination of capillary- and clay-bound water cutoffs and effect of clay distribution on the NMR data. Finally, I have been working recently as a partner on an international project that focuses on the use of airborne EM methods for large-sclae mapping of peat lands in Indonesia.

Honors & Awards


  • Individual Postdoctoral Grant, The Danish Council for Independent Research (2013)
  • Outstanding Student Paper Award, American Geophysical Union (2011)
  • Research Visiting Grant, Aarhus University (2010)
  • Distinguished Master Student Award, University of Tehran (2007)

Education & Certifications


  • Ph.D., Aarhus University, Geophysics (2012)
  • M.Sc., University of Tehran, Geophysics (2007)

Projects


  • Integrating geophysical data to add to our groundwater supply: a new approach for efficient evaluation of recharge sites (10/1/2017 - Present)

    Locating new groundwater recharge sites is a critical part of sustainably managing groundwater resources. Agricultural fields, which are generally already linked to existing surface water conveyance infrastructure, are an appealing first choice. However, depending on the geology in the area, recharge water may sit stagnant on the surface and take long periods of time to infiltrate. How can we accurately map out the subsurface, and thereby prioritize and plan our recharge infrastructure appropriately?

    We conducted a study in the Tulare Irrigation District (TID) with the goal of assessing the utility of a recently developed geophysical imaging method for evaluating potential dedicated recharge sites as well as the suitability of farm fields for recharge through surface spreading. We employed a towed time-domain electromagnetic (tTEM) system, developed at Aarhus University, Denmark, that is specifically designed for high-resolution imaging of the upper 70-100 m of the subsurface. The system is towed behind an ATV while continuously imaging the subsurface geology. As a result, an area of 40-80 hectares can be covered in one day with dense coverage (10-20 m line spacing). The results are presented as a 3-D resistivity image of the subsurface with high resolution. The new geophysical mapping system, tTEM, has the potential to be a valuable method for assessing the suitability of sites for recharge, thereby decreasing the risk associated with large investments and increasing the effectiveness of recharge operations.

    Further information about the project can be found at:
    https://gemcenter.stanford.edu/research/integrating-geophysical-data-add-our-groundwater-supply-new-approach-efficient-evaluation

    Location

    Tulare, California

    Collaborators

    • Ahmad Behroozmand, Senior Geophysicist, Department of Geophysics - Geophysics, Department of Geophysics - Geophysics
    • Rosemary Knight, The George L. Harrington Professor in the School of Earth Sciences, Stanford University
    • Esben Auken, Professor, Aarhus University, Denmark
    • Aaron Fukuda, General Manager, Tulare irrigation District

    For More Information:

  • Aquifer characterization in the Indian Wells Valley, California using geophysical techniques, Stanford University (October 1, 2015 - Present)

    The Indian Wells Valley is a terminal basin in an arid region east of the southern Sierra Nevada. Stakeholders in the valley are seeking to better understand their local groundwater basin. In an effort to attain sustainable management, stakeholders are considering using brackish water from the lower portion of the aquifer system to help meet overall water needs in this groundwater-dependent basin. In specific, local stakeholders need tools to assess the location, depth, and overall geometry of the main aquifers and aquitards in the system, and would need tools to differentiate brackish groundwater from fresh groundwater.

    In partnership with the Indian Wells Valley Water District, the town of Ridgecrest, and the China Lake Naval Air Weapons Station (NAWS), we undertook a pilot study in 2015-2016 to assess the combined use of time-domain electromagnetics (TEM), surface nuclear magnetic resonance (NMR) and logging NMR to characterize a complex fresh/brackish aquifer system in their groundwater basin. TEM is a geophysical technique that provides information on the electrical resistivity of the subsurface, which is affected by sediment texture (sands are more resistive than clays) and groundwater salinity (fresh water is more resistive than brackish water). NMR was used to augment the TEM survey, because this technique is sensitive to the volume of water in the subsurface without any effect from the salinity of that water.

    Following the pilot project, airborne EM (AEM) data was acquired across the basin in November 2017 to better understand the basing groundwater system. A resistivity model of the basin, obtained from inversion of the AEM data, provides details about the basin hydrogeological variations. A hydrogeological conceptual model of the basin is being developed by integration of geophysical and hydrogeological data.

    Location

    Stanford, CA

    Collaborators

    • Ahmad Behroozmand, Senior Geophysicist, Department of Geophysics - Geophysics, Department of Geophysics - Geophysics
    • Rosemary Knight, The George L. Harrington Professor in the School of Earth Sciences, Stanford University
    • Jesse Michael Crews, Department of Geophysics - Geophysics

    For More Information:

  • Comparing Laboratory and Borehole NMR in Unconsolidated Aquifers, Stanford University (July 1, 2014 - 10/31/2016)

    The nuclear magnetic resonance (NMR) technique has become popular in groundwater studies because it responds directly to the presence and mobility of water in a porous medium. In unconsolidated aquifers, attempts have been made in boreholes to establish the NMR-K relationship by acquiring NMR and hydraulic conductivity (K) data. However, it is challenging to obtain reliable estimates of the NMR parameters from such borehole data. Laboratory-NMR data could aid in development of NMR-K models, as is typically done in the petroleum industry. However, the challenge has been obtaining high-quality laboratory samples from unconsolidated aquifers.

    At our study site in Denmark, we employed sonic drilling, which minimizes the disturbance of the surrounding material and provides both good borehole conditions for logging, as well as core samples for laboratory studies. We acquired logging data consisting of NMR logging, electromagnetic (EM) induction, gamma, and magnetic susceptibility. In addition, we extracted twelve 7.6 cm diameter samples for laboratory measurements. Our samples were used for laboratory NMR measurements in their initial condition and size. We also prepared two sets of smaller subsamples to investigate the importance of sample size and condition on the NMR laboratory measurement.

    This study addressed the main challenges inherent in conducting laboratory and logging NMR in unconsolidated near-surface aquifers: the borehole conditions and the sample conditions and size. A detailed comparison of laboratory and logging NMR data from the study site suggests sonic drilling to be a suitable drilling method as it is known to produce essentially no disturbed zone around the PVC casing and provide continuous, undisturbed samples of the unconsolidated materials. With this and with our careful sample preparation, the results of this study showed good agreement between the logging and laboratory NMR estimated water contents and relaxation times. We investigated the influence of sample size and condition by acquiring NMR data on two sets of smaller undisturbed and disturbed subsamples. When the T2 distributions of the small-disturbed and small-undisturbed samples were compared to the T2 distributions of the large samples, we observed different distributions both in shape and time. This study recommends use of larger samples for laboratory NMR experiments and concludes that repacking of samples has a large impact on the NMR measurements.

    Location

    Stanford, California

    Collaborators

    • Ahmad Behroozmand, Senior Geophysicist, Department of Geophysics - Geophysics, Department of Geophysics - Geophysics
    • Rosemary Knight, The George L. Harrington Professor in the School of Earth Sciences, Stanford University
    • Esben Auken, Professor, Aarhus University

    For More Information:

Professional Affiliations and Activities


  • SCIENTIFIC COMMITTEE MEMBER AND SESSION CHAIR, Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) 2017 (2016 - 2018)
  • SCIETIFIC COMMITTEE MEMBER, The Near Surface Geoscience Conference 2017 (2016 - 2017)
  • SCIENTIFIC JOURNAL GUEST EDITOR, Geophysics (2015 - 2016)
  • SCIENTIFIC COMMITTEE MEMBER AND CO-ORGANIZER, 6th International Workshop on Magnetic Resonance (2014 - 2015)
  • ARTICLE REFEREE OF SCIENTIFIC JOURNALS, Geophysics, Geophysical Research Letters, Water Resources Research, Geophysical Journal International, Journal of Applied Geophysics, Near Surface Geophysics, Iranian Journal of Geophysics (2012 - Present)
  • PROFESSIONAL MEMBERSHIP, American Geophysical Union (AGU), Society of Exploration Geophysicists (SEG), Environmental and Engineering Geophysical Society (EEGS), European Association of Geoscientists and Engineers (EAGE), European Geosciences Union (EGU) (2011 - Present)

All Publications


  • Accounting for relaxation during pulse effects for long pulses and fast relaxation times in surface nuclear magnetic resonance Geophysics Grombacher, D., Behroozmand, A. A., Auken, E. 2017; 82 (6): JM23-JM36

    View details for DOI 10.1190/GEO2016-0567.1

  • Successful Sampling Strategy Advances Laboratory Studies of NMR Logging in Unconsolidated Aquifers Geophysical Research Letters Behroozmand, A. A., Knight, R., Müller-Petke, M., Auken, E., Barfod, A., Ferré, T., Vilhelmsen, T., Johnson, C., Christiansen, A. V. 2017

    View details for DOI 10.1002/2017GL074999

  • Anthropogenic wetlands due to over-irrigation of desert areas; A challenging hydrogeological investigation with extensive geophysical input from TEM and MRS measurements Hydrol. Earth Syst. Sci. Behroozmand, A. A., Teatini, P., Pedersen, J. B., Auken, E., Tosatto, O., Christiansen, A. V. 2017; 21: 1527–1545

    View details for DOI 10.5194/hess-2016-630

  • Comparison of stabiliser functions for surface NMR inversions Near Surface Geophysics Grombacher, D., Fiandaca, G., Behroozmand, A. A., Auken, E. 2017; 15: 533-544
  • Processing of surface-nuclear magnetic resonance data from sites with high noise levels GEOPHYSICS Larsen, J. J., Behroozmand, A. A. 2016; 81 (4): WB75-WB83
  • Increasing the resolution and the signal-to-noise ratio of magnetic resonance sounding data using a central loop configuration GEOPHYSICAL JOURNAL INTERNATIONAL Behroozmand, A. A., Auken, E., Fiandaca, G., Rejkjaer, S. 2016; 205 (1): 243-256

    View details for DOI 10.1093/gji/ggw004

    View details for Web of Science ID 000374479800019

  • Processing of surface-NMR data from sites with high noise levels Geophysics Larsen, J. J., Behroozmand, A. A. 2016; 81 (4): WB75-WB83

    View details for DOI 10.1190/geo2015-0441.1

  • An overview of a highly versatile forward and stable inverse algorithm for airborne, ground-based and borehole electromagnetic and electric data EXPLORATION GEOPHYSICS Auken, E., Christiansen, A. V., Kirkegaard, C., Fiandaca, G., Schamper, C., Behroozmand, A. A., Binley, A., Nielsen, E., Efferso, F., Christensen, N. B., Sorensen, K., Foged, N., Vignoli, G. 2015; 46 (3): 223-235

    View details for DOI 10.1071/EG13097

    View details for Web of Science ID 000360648400001

  • A Review of the Principles and Applications of the NMR Technique for Near-Surface Characterization SURVEYS IN GEOPHYSICS Behroozmand, A. A., Keating, K., Auken, E. 2015; 36 (1): 27-85
  • Joint inversion of aquifer test, MRS, and TEM data WATER RESOURCES RESEARCH Vilhelmsen, T. N., Behroozmand, A. A., Christensen, S., Nielsen, T. H. 2014; 50 (5): 3956-3975
  • A comprehensive study of parameter determination in a joint MRS and TEM data analysis scheme NEAR SURFACE GEOPHYSICS Behroozmand, A. A., Dalgaard, E., Christiansen, A. V., Auken, E. 2013; 11 (5): 557-567
  • Surface-NMR measurements of the longitudinal relaxation time T-1 in a homogeneous sand aquifer in Skive, Denmark JOURNAL OF APPLIED GEOPHYSICS Walbrecker, J. O., Behroozmand, A. A. 2012; 87: 46-52
  • Efficient full decay inversion of MRS data with a stretched-exponential approximation of the distribution GEOPHYSICAL JOURNAL INTERNATIONAL Behroozmand, A. A., Auken, E., Fiandaca, G., Christiansen, A. V., Christensen, N. B. 2012; 190 (2): 900-912
  • Improvement in MRS parameter estimation by joint and laterally constrained inversion of MRS and TEM data GEOPHYSICS Behroozmand, A. A., Auken, E., Fiandaca, G., Christiansen, A. V. 2012; 77 (4): WB191-WB200
  • Coupled hydrogeophysical inversion using time-lapse magnetic resonance sounding and time-lapse gravity data for hydraulic aquifer testing: Will it work in practice? WATER RESOURCES RESEARCH Herckenrath, D., Auken, E., Christiansen, L., Behroozmand, A. A., Bauer-Gottwein, P. 2012; 48
  • Using the determinant data as a replacement for the static shift correction in magnetotelluric surveys Journal of the Earth and Space Physics Oskooi, B., Javaheri, A. H., Behroozmand, A. A. 2012; 37 (4): 67-77
  • A review of the MT data processing Journal of the Earth and Space Physics Oskooi, B., Behroozmand, A. A. 2008; 34 (2): 15-25
  • 2D interpretation of the airborne VLF data Iranian Journal of Geophysics oskooi, B., Behroozmand, A. A. 2007; 1 (1): 13-19
  • 1D interpretation of the Magnetotelluric data in Inche - Boroon, Golestan, Iran Journal of the Earth and Space Physics Behroozmand, A. A., Oskooi, B. 2007; 33 (2): 55-67
  • Anthropogenic wetlands due to over-irrigation of desert areas: a challenging hydrogeological investigation with extensive geophysical input from TEM and MRS measurements HYDROLOGY AND EARTH SYSTEM SCIENCES Behroozmand, A. A., Teatini, P., Pedersen, J. B., Auken, E., Tosatto, O., Christiansen, A. V. 2017; 21 (3): 1527-1545
  • Aquifer characterization in the Indian Wells Valley, California using surface geophysical techniques Groundwater Resources Association of California Workshop Behroozmand, A. A., Crews, J., Knight, R., Grunewald, E. 2016
  • A detailed comparison of laboratory and borehole NMR estimated parameters in unconsolidated aquifers AGU Fall Mereting Behroozmand, A. A., Auken, E., Christiansen, A. V., Müller-Petke, M., Vilhelmsen, T., Barford, A., Ferré, T., Knight, R. 2016
  • Accounting for relaxation during pulse effects in surface NMR for long pulses and fast relaxation times AGU Fall Meeting Grombacher, D., Behroozmand, A. A., Auken, E. 2016
  • Anthropogenic wetlands due to over-irrigation of desert areas; A challenging hydrogeological investigation with extensive geophysical input from TEM and MRS measurements Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) Behroozmand, A. A., Teatini, P., Pedersen, J., Auken, E., Tosatto, O., Christiansen, A. V. 2016
  • Sensitivity analysis of central-loop surface NMR data Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) Behroozmand, A. A., Fiandaca, G., Auken, E. 2015
  • Improved resolution and signal-to-noise ratio of magnetic resonance sounding data using a central loop configuration 6th International Workshop on Magnetic Resonance in the Subsurface Behroozmand, A. A., Auken, E., Fiandaca, G., Rejkjaer, S. 2015
  • Processing of surface-NMR data from sites with high noise levels 21th European Meeting of Environmental and Engineering Geophysics Larsen, J. J., Behroozmand, A. A. 2015
  • Sharp SCI: a new tool for blocky reconstructions ASEG-PESA Assembly Viezzoli, A., Hoeyer, A., Behroozmand, A. A., Vignoli, G. 2015
  • A comprehensive sensitivity analysis of central-loop MRS data European Geosciences Union (EGU) General Assembly Behroozmand, A. A., Auken, E., Dalgaard, E., Rejkjaer, S. 2014
  • On the sensitivity analysis of separated-loop MRS data AGU Fall Meeting Behroozmand, A. A., Auken, E., Fiandaca, G. 2013
  • A framework for joint inversion of aquifer test, MRS and TEM data Modflow and more Vilhelmsen, T., Behroozmand, A. A., Christensen, S., Nielsen, T. 2013
  • Focused multi-layer inversion of magnetic resonance sounding data 19th European Meeting of Environmental and Engineering Geophysics Fiandaca, G., Vignoli, G., Behroozmand, A. A., Auken, E. 2013
  • Improvement in MRS parameter estimation – a closer step toward hydrogeological interpretations SEG-AGU Hydrogeophysics Workshop Behroozmand, A. A., Auken, E., Christiansen, A. V. 2012
  • A comprehensive study of parameter determination in a joint MRS and TEM data analysis scheme 5th International Meeting on Magnetic Resonance Behroozmand, A. A., Dalgaard, E., Christiansen, A. V., Auken, E. 2012
  • MRS parameter estimation – improvement by joint and laterally constrained inversion of MRS and TEM data 18th European Meeting of Environmental and Engineering Geophysics Behroozmand, A. A., Auken, E., Fiandaca, G., Christiansen, A. V. 2012
  • Full FID inversion of MRS data 17th European Meeting of Environmental and Engineering Geophysics Behroozmand, A. A., Auken, E., Fiandaca, G., Dalgaard, E., Larsen, J. J. 2011
  • Surface NMR measurement of the longitudinal relaxation time T1 in a homogeneous sandy aquifer in Skive, Denmark AGU Fall Meeting Walbrecker, J., Behroozmand, A. A. 2011
  • Joint inversion of MRS and TEM data AGU Fall Meeting Behroozmand, A. A., Auken, E., Fiandaca, G., Christiansen, A. V. 2011
  • 1D and 2D interpretation of the MT data to detect subsurface salinity and conductive structures in Inche-boroon, Golestan 24th IUGG General Assembly Javaheri, A. H., Oskooi, B., Behroozmand, A. A. 2007
  • Interpretation of the MT data to detect Iodine bearing structures in Gorgan plain, Iran 18th International Workshop on Electromagnetic Induction in the Earth Behroozmand, A. A., Oskooi, B. 2006
  • The effect of PMR measurement in optimum interpretation of geoelectrical section 12th Iranian National Geophysical conference Hafizi, M. K., Behroozmand, A. A., SanaieKamal, H. 2006