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Frequently asked questions (FAQ) on electrical geophysical equipment and software

How to convert conductivity to resistivity?

Are there any difference between LandMapper ERM-01 and other equipment available on the market?

How your equipment calculates electrical resistivity?

How to calculate geometrical coefficient K?

Does electrical resistivity correlate with any soil properties?

Can your equipment measure electrical resistivity/conductivity in soil and water samples?

How to determine the depth of the measurements?

More help...

How to convert conductivity to resistivity?

Electrical resistivity (ER) is reciprocal to conductivity (EC) and results can be easily recalculated using formula EC=1/ER or vice versa ER=1/EC. Electrical resistivity is more convenient to use on non-saline soils, where conductivity can be mSm/m, while resitivity measures in 102-103 Ohm m range. 1000 Ohm m equals 1 mSm/m. You can find more conversions to ppm, TDS, grains of salt in this flyer.

Happy New 2017 Year!

 

All of us at Landviser, LLC (USA) and IP GeoPro (Russia) are wishing our friends, collegues, customers and everybody else around the world Happy Holidays and a Great New Year! Looking forward to change, trust and fairness for all in 2017!!! We, as a small geo-consulting company, would continue to do our best in studying our Morther Earth and bringing Joy to the World!

Happy New 2016 Year!

All of us at Landviser, LLC (USA) and IP GeoPro (Russia) are wishing our friends, collegues, customers and everybody else around the world Happy Holidays and Great New Year!

LandMapper ERM-02: handheld meter for near-surface electrical geophysical surveys (FastTIMES December 2010)

was published in December, 2010 issue of FastTIMES, online peer-reviewed journal of EEGS. To cite this publication use:FastTIMES dec 2010 Agriculture: A budding field in Geophysics

Golovko, Larisa, Anatoly Pozdnyakov, and Antonina Pozdnyakova. “LandMapper ERM-02: Handheld Meter for Near-Surface Electrical Geophysical Surveys.” FastTIMES (EEGS) 15, no. 4 - Agriculture: A Budding Field in Geophysics (December 2010): 85–93. http://www.landviser.net/webfm_send/69

Registered users can download PDF of full text of proceedings paper from our website. Or browse online version below and leave your comments. You might also like to go to EEGS website to get PDFs of other publications on applications of geophysics to near-surface environmental problems published in this popular FREE online scientific magazine.

Abstract

On-the-go sensors, designed to measure soil electrical resistivity (ER) or electrical conductivity (EC) are vital for faster non-destructive soil mapping in precision agriculture, civil and environmental engineering, archaeology and other near-surface applications. Compared with electromagnetic methods and ground penetrating radar, methods of EC/ER measured with direct current and four-electrode probe have fewer limitations and were successfully applied on clayish and saline soils as well as on highly resistive sandy soils, such as Alfisols and Spodosols. However, commercially available contact devices, which utilize a four-electrode principle, are bulky, very expensive, and can be used only on fallow fields. Multi-electrode ER-imaging systems applied in deep geophysical explorations are heavy, cumbersome and their use is usually cost-prohibited in many near-surface applications, such as forestry, archaeology, environmental site assessment and cleanup, and in agricultural surveys on farms growing perennial horticultural crops, vegetables, or turf-grass. In such applications there is a need for accurate, portable, low-cost device to quickly check resistivity of the ground on-a-spot, especially on the sites non-accessible with heavy machinery.

Местоположение

Laramie, WY 41° 18' 40.9212" N, 105° 35' 27.9636" W

Электрофизика почв и не только - лекция

Лопата иногда представляется неотъемлемым атрибутом практикующего почвоведа. Однако почвовед может выглядеть и по-другому.

В этом случае его инструментом становится электронный прибор и моток проводов. В своей лекции я постараюсь рассказать, какие возможности открывают перед почвоведом электрофизические методы, где-то дополняя уже ставшие классическими способы обследования почв, а где-то являющиеся и единственным методом, которым можно решить поставленные задачи.

References

Bedmar, A.P., and Araguás, L.A., 2002, Detection and prevention of leaks from dams: Taylor & Francis, Exton, PA.

Carrow, R.N., and Duncan, R.R., 2004, Soil salinity monitoring: present and future: Golf course management, no. November, p. 89-92.

Corwin, R., 1990, The self-potential method for environmental and engineering applications: Geotechnical and Environmental Geophysics, Soc. Expl. Geophysics, Tulsa, OK, p. 127-143.

Special instrumentation for soil SP method is needed

solid state Ag-AgCl electrodesLandMapper ERM-02, in addition to electrical conductivity and resistivity measurements also allows non-invasively measure natural electrical potentials in soils and plants when two special non-polarizing electrodes are connected to MN terminals (Figure 3).

Measuring Electrical Potentials with LandMapper ERM-02

Electrical geophysical methods are classified as methods measuring natural electrical potentials of the ground without introducing additional electrical field and methods utilizing artificial electrical or electromagnetic fields to measure soil electrical parameters. Method of self-potential (SP) measures the naturally existing electrical potentials in soils and “bio-potentials” in plant, which are important in agriculture. Despite growing popularity of electrical resistivity/conductivity methods in agriculture, method of self-potential is rarely used.

Table 2. Technical Specifications of LandMapper ERM-02

Table 2. Technical Specifications of LandMapper ERM-02

Range of measurements   ……………………………………….……..    ER= 0.1-1 106 Ohm m

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