Marine Magnetics SeaSPY Magnetometer

Available as:
  • Rental
  • Sale (ex rental)

Marine Magnetics SeaSPY Magnetometer – Available for rental, hire and ex-rental purchase from Ashtead Technology.

The SeaSPY magnetometer product eliminates many of the inherent problems associated with other marine magnetomers such as orientation restrictions, sensor realignment, time and temperture drift and poor absolute accuracy. Marine Magnetic's SeaSPY magnetometer measures the ambient magnetic field using a specialized branch of nuclear Magnetic Resonance technology, applied specifically to hydrogen nuclei. The SeaSPY sensor is unique in that it is entirely omnidirectional. The amount of signal produced by the sensor is completely independent of magnetic field direction. You never have to orient your sensor, because it is already optimized to work around the World.

The SeaSPY Towfish includes high sensitivity omnidirectional Overhauser sensor, electronics module containing all of the driving electronics, leak detector, 4 lead weights and SeaLINK data acquisition and GPS logging software for Windows. Also included tow cable, communication transceiver, power supply, altimeter and pressure sensor.

Key features

  • Digital System
  • High Sensitivity
  • Highest Absolute Accuracy
  • Maintenance Free Sensors, No Realignment and No Consumable Parts
  • Ultra low power consumption
  • Worldwide operation with no restrictions


  • Cable & Pipeline Survey
  • Shipwreck, Search and Salvage
  • Environmental Survey
  • Exploration Geophysics

Technical specifications

Absolute Accuracy0.2nT
Sensor Sensitivity0.01nT
Counter Sensitivity0.001nT
Timebase stability1ppm, -45°C to +60°C
Range18,000nT to 120,000nT
Gradient ToleranceOver 10,000 nT/m
Sampling Range4Hz - 0.1Hz
Power Supply15VDC-35VDC or 100-240VAC
Operating Temperature-45°C to +60°C
Temperature Sensor-45°C to +60°C, 0.1 step


Towfish Weight in Air124 L x 12.7 D cm49 L x 5 D in.16 kg35 lbs
Towfish Weight in Water2 kg4.4 lbs
Tow Cable Weight in Air1(outer) x 16.5 (bending) cm0.4 (outer) x 6.5 (bending) in.125 g/m84 lb / 1000 ft
Floatation Cable Weight in Air272 g/m183 lbs/1000 ft
Floatation Cable Weight in Water-20 g/m-13.5 lbs/1000 ft