Geometrics G-858 MagMapper Cesium Magnetometer
The Geometrics G-858 MagMapper is a high sensitivity fast sampling walking magnetometer for magnetic surveys and detailed mapping of the Earth magnetic field. It uses a self oscillating split beam cesium vapor sensor and it can be used as a single sensor magnetometer or as a gradiometer with two sensors. The Geometric G-858 has long been an industry standard for archaeological, environmental, engineering, and geophysical work and it is simple enough to be used by inexperienced personnel.
Key Features Geometric G-858
- Cesium vapor sensor: a non radioactive self oscillating split beam sensor with excellent sensitivity and a noise level of less than 0.008 nT/√Hz RMS
- Single or dual sensor operation: easily switch from a single sensor survey to a vertical or horizontal gradiometer survey
- Operating range: 20,000 to 100,000 nT for worldwide use
- Fast sampling: a high sampling rate lets the operator survey at a fast walking pace without gaps in coverage saving time and money on large surveys
- Continuous or discrete station recording: choose the mode that suits the job
- Graphical interface: design survey grids see your position and the current data profile during the survey, and select sensitivity resolution, and recording rate
- Low AC field interference: survey near power lines when necessary
- Ultra-stable sensors: no need to calibrate the sensors
- Wider search radius: use a horizontal transverse gradiometer configuration
- Low heading error: about 1.5 nT including the backpack and GPS
- Rugged and weatherproof: survives a three foot drop onto a hard surface
- GPS options: the G-858G variants add GPS positioning with the G-858GAP including an ergonomic backpack GPS, and a second cesium sensor
- Data handling: stores magnetometer data, time, event marks, field notes, and XYZ or GPS locations with transfer to a PC from the magnetometer GPS or base station
- Battery life: about 6 hours of operation as a magnetometer with GPS and about 3 hours as a gradiometer with GPS
- Warranty: 1 year on the G-858 and sensor and 1 year on accessories
Typical Applications Geometric G-858
- Archaeological surveys
- Unexploded ordnance (UXO) and buried metal detection
- Environmental and engineering site investigations
- Geological mapping and mineral exploration
- Locating buried tanks, pipes, and drums
- Base station and diurnal magnetic monitoring
Why Choose It
The Geometric G-858 gives you cesium grade sensitivity in a portable system that can be used by a single operator. Quick, gap free walking surveys flexible gradiometer setups, and sensors that never need calibration keep survey costs down while data quality stays high.
