Dr. Larisa Golovko (President of Landviser, LLC) will be presenting "Geophysical Methods of Electrical Resistivity and Self-Potential in Agriculture" in first of 

Agricultural Geophysics Webinar Series: "Application of Geophysical Methods to Agriculture: Methods Employed"

A live webinar on the application of geophysics to agriculture will be offered on:

Tuesday, February 18, 2014, from 3pm - 4:30pm EST
(2:00 - 3:30 CST, 1:00 - 2:30 MST, 12:00 - 1:30 PST)

This first in a series of agricultural geophysics webinars will focus on the near-surface geophysical methods presently being used for agricultural purposes, which include resistivity, self-potential, electromagnetic induction, ground penetrating radar, dielectric sensors, VIS/NIR/MIR spectrometry, gamma ray spectrometry, mechanical soil compaction sensors, and ion selective potentiometry. Five presenters will provide a short overview of agricultural geophysical methods during the first 30 minutes of the webinar. The last hour of the webinar will be devoted to a panel discussion with the presenters, who will answer questions from the audience.

Местоположение

Landviser, LLC is offering advanced equipment for multi-frequency electromagnetic sounding and profiling - AEMP-14 - manufactured by KB Electrometry Ltd in Novosibirsk, Russia.

Price of the system ordered through us is the same as listed on Nemfis.ru. Registered website users can view price of for the complete AEMP-14 system including field hand-held PDA, GPS, laptop with pre-loaded EM interpretation software and training videos in current catalog.  

Please, request your personalized quotation from us: info@landviser.com or call 1-609-412-0555 / 1-888-306-LAND. The system is shipped worldwide from Russia, shipping costs will vary. See specification table at the bottom of this page on estimated weight of the system and components.

Landviser, LLC is offering advanced equipment for deep electrical tomography - Siber-48 - manufactured by KB Electrometry, Ltd in Novosibirsk, Russia. Since 2012 they started to produce modificated version of "SibER". New device has new safer body, powerfull generator (inject current up to 2A), provide more stable and faster measurments.

Price of the system ordered through us is the same as listed on Nemfis.ru. Registered users can view complete price of the SibER-48 and SibER-64 equipped with two standard 5-m spaced cables in current catalog. Custom spacing of electrode connectors on the cables is also available per request.

Please, request your personalized quotation from us: info@landviser.com or call 1-609-412-0555 / 1-888-306-LAND. The system is shipped worldwide from Russia, shipping costs will vary. See specification table at the bottom of this page on estimated weight of the system and components.

Example of electrodes arrangement and measurement sequence that can be used for a 2-D electrical imaging survey is shown on the left. Many different multi-electrode systems have been developed over the past 15 years using different arrangements of the cables and measurement strategies (Loke, 2011). This program is designed to invert large data sets (with about 200 to 100000 data points) collected with a system with a large number of electrodes (about 25 to 16000 electrodes). The survey is usually carried out with a system where the electrodes are arranged along a line with a constant spacing between adjacent electrodes. However, the program can also handle data sets with a non-uniform electrode spacing. RES2DINV program can be used for surveys using the Wenner, pole-pole, dipole-dipole, pole-dipole, Wenner-Schlumberger, gradient and equatorial dipole-dipole (rectangular) arrays. In addition to these common arrays, the program even supports non-conventional arrays with an almost unlimited number of possible electrode configurations (Loke et al. 2010). You can process pseudo sections with up to 16000 electrode positions and 70000 data points at a single time on a computer with 4 gigabytes (GB) of RAM. Besides normal surveys carried out with the electrodes on the ground surface, the program also supports aquatic and cross-borehole surveys.

Locations

Establishments of orchards and vineyards are long-term and money-intensive, but highly pay-off projects. This study allowed developing procedure for incorporating geophysical survey data into recommendations of usage skeletal soils under orchards. Geophysical methods of electrical resistivity, such as VES and four-electrode profiling provided the information about spatial distributions of stones in skeletal soils.  The resistivity of rocks or stones is much higher (about 10⁴-10¹² ohm m) than the resistivity of soil horizons with any texture. Therefore, high resistivity will indicate the presence of stones in soil profiles.

Study was conducted on skeletal soils (Paleoxerolls and Lithic Xerorthents) formed on carbonate-cemented marine deposit, limestone, or pebbles of alluvial origin in western part of Crimea Peninsula, Ukraine. The stone content varied from 2 to 90% of fragments coarse than 2 mm by volume and stony layers occurred in soil profiles at the depth as shallow as 12 cm.

Местоположение

Electrical geophysical methods were successfully used for exploration of gas and oil fields (Kalenev, 1970). However, the methods are not widely used for estimation of the soil pollution with petroleum products (Znamensky, 1980; Pozdnyakov et al., 1996a). The possibility of using the methods of electrical resistivity to evaluate the places of petroleum pollution or natural petroleum and gas deposits is based on highly different resistivities of soil and petroleum products. Petroleum and various products of petroleum manufacture, such as oil, gasoline, bitumen, and kerosene have very high electrical resistivity compared with soils. Electrical resistivity of petroleum varies from 10⁴ to 10¹⁹ ohm m (Fedinsky, 1967), whereas resistivity of petroleum-saturated sand is much lower (2200 ohm m) (Znamensky, 1980), but is still higher than that of any non-polluted soil.

Soil pollution by the products of gas and petroleum mining was studied near Urengoi in northwest Siberia, Russia. The virgin soils, Glacic and Aquic Haplorthels, were extremely polluted with various by-products of petroleum extraction and manufacturing, such as bitumen, gasoline, kerosene, and mining brine solutions. The study area was thoroughly investigated with four-electrode profiling on 1.2-m array and vertical electrical sounding.

Местоположение

Mapping alluvial soils of humid areas with electrical geophysical methods: We tested the electrical geophysical methods of non-contact electrical profiling (NEP) and electrical profiling (EP) for mapping peat and mineral alluvial soils formed in the glacial valley of Yachroma river. More >>

Vertical Electrical Sounding to detect groundwater levels in arid areas: The approximate location of the groundwater table was estimated by a visual inspection of the VES curve. The AB/2 value with the sharp change to the low resistivity (3-20 ohm m) was selected from each VES profile...More >>

Evaluation of stone contents in soils with electrical geophysical methods to aid orchard planning: Geophysical methods of electrical resistivity, such as VES and four-electrode profiling provided the information about spatial distributions of stones in skeletal soils.  High resistivity will indicate the presence of stones in soil profiles. More >>

Application of the geophysical methods of electrical resistivity in precision farming:  One of the challenges facing the adoption of precision agriculture technology is the identification of productivity-related variability of soil properties accurately and cost-effectively. More >>