Description
The ABEM GroundTEM i5, i10 & i20 are user-friendly, app-controlled instruments that complement the existing WalkTEM range perfectly. They make groundwater and environmental TEM surveys more affordable, less complex, and quicker to deploy, with a one-box lightweight solution.
Application areas
Groundwater
A high sensitivity to conductive materials makes TEM extremely useful in groundwater studies, for example differentiating between fresh, brackish and saline deposits, monitoring drawdown and recharge of an aquifer, or simply estimating its extents by building up profiles or grids of soundings.
Environmental
TEM provides a rapid means of surveying for a range of environmental applications from identifying potentially hazardous clay units within a geological sequence, to mapping and monitoring dynamic features such as permafrost thickness or pollution plumes.
Features
Affordable but capable
Redefining what you can expect from an entry-level system
The lower starting price of the GroundTEM i-Series does not mean this is a ‘stripped-back’ system. It benefits from dual-moment output: measurements configured for both shallow and deeper responses are collected in a single measurement period, and then combined in the same data file. There is a choice of three instruments (5 Amp, 10 Amp and 20 Amp), three transmitter loop sizes (20 × 20 m, 40 × 40 m and 80 x 80 m), flexible 3 × 3 m and 5 × 5 m receiver coils, and the innovative Explorer Coils for fast, affordable profiling and area survey.
Quick and easy to use
Fast in-field set-up and a user-friendly mobile app simplifies use of the GroundTEM i-Series
Roll out the receiver coil, then the transmitter loop and attach both to the instrument. There is no right-or-wrong way to lay these out; they are not directional. Alternatively, plug together the carry frames and mount the cabling for the Explorer Coils, and attach the strain relief to the instrument case.
Then, start the GroundTEM App, select a survey line and station number, and follow the on-screen prompts to choose a measurement script. The system is ready to go: select how long you wish to measure for and press the “play” button.
Watch data come in live and even take the option to benefit from real-time inversion (available mid-2025) to see processed results immediately.
Simple to deploy
Lightweight, with all components shipped in a single Peli-style case
For the regular 20 m, 40 m and 80 m Tx configurations, the whole system ships in a single transport case, with integral wheels and handles. Arrive on site, open the case and the instrument, transmitter loop, and receiver coil are ready to lay out. Power comes from two or three (GroundTEM i20) small Li-ion battery packs that mount inside the instrument case, removing the need for heavy, external 12 V batteries.
The transport case weighs under 32 kg in the 20 m or 40 m Tx configuration (if batteries and charger are taken separately) and thus can be shipped as hold luggage on regular flights. In extreme cases, the system can be packed down into smaller cases for even easier transportation.
A dedicated peli-style case is provided for the Explorer Coils, which also features integral wheels and carry handles. If an i-Series instrument is purchased with only Explorer Coils, a small case is supplied for the instrument and accessories, with the Explorer Coils separate. If an i-Series instrument is bought with a 20 m, 40 m, or 80m Tx loop and Explorer Coils a large case is supplied to hold the instrument, Tx loop, Rx coils and accessories, with the Explorer Coils in their own case.
Explorer coils
For rapid shallow TEM measurements
The Explorer Coils are an essential accessory for the GroundTEM i-Series. They comprise a pair of Tx and Rx coils, mounted on carry frames, that make moving between stations simple and fast, even in difficult terrain. The Explorer Coils can be purchased as part of a new GroundTEM i-Series package, or added to an existing system.
The Explorer Coils offer a budget-friendly means of producing either 2D profiles or large area surveys from a series of 1D soundings. They are available in two sizes: 3 × 3 m for depths down to 120 m and a 1.6 × 1.6m set for shallow surveys, providing better near-surface detail, especially useful on sites where space might be limited.
Real-time inversion
View processed resistivity models instantly while collecting TEM data in the field
Real-time inversion is now available as a premium upgrade for the GroundTEM i-Series (i5, i10, i20), when running v2.0.3 of the GroundTEM i-Series App or higher. Real-time inversion and stacked decay curves / apparent resistivity charts, offers a clearer overview compared to viewing individual raw data from each cycle. The results appear automatically in a new view tab in the App.
Existing GroundTEM units can be upgraded remotely with support from our team. The system will continue to work without a subscription – data collection and system configuration is in the basic, free package. New and existing customers get a 3-month free trial. Find out more about Real-time inversion and the free trial here:
Selected Technical Specification
General
| GroundTEM App | Android |
| Onboard power | 2 × Li-ion (i5 / i10) |
| (14.4 V, 6.8 Ah, 99.4 Wh) | 2 × Li-ion (i20) |
| Weight (incl. batteries) | 6 kg (i5 / i10) 8 kg (i20) |
| Dimensions | 36 × 27 × 14 cm |
| Environment | IP65, -20 to +50 °C |
Transmitter
| Output current | Dual-moment |
| 1 A / 5 A (i5) 1 A / 10 A (i10) 1 A / 20 A (i20) | |
| Loop options | 20 × 20 m, single turn |
| 40 × 40 m, single turn | |
| 80 × 80 m, single turn | |
| Explorer Coils |
Receiver
| Channels | 1 |
| Coil Options | Flexible, 3 × 3 m, 4 turns |
| Flexible, 5 × 5 m, 4 turns | |
| Explorer Coils | |
| GNSS | Onboard |
Explorer Coils
| 1.6 m Explorer Coils | 1.65 x 1.65 m, 2 turn Tx |
| 1.65 x 1.65 m, 4 turn Rx | |
| 3.0 m Explorer Coils | 3 x 3 m, 2 turn Tx |
| 3 x 3 m, 4 turn Rx | |
| Coil separation | 10 m |
Schematic layout
Schematic diagrams showing the Explorer Coils configuration.
