CRAB System

Mobile seismic system for marine surveys and monitoring on the shelf and in transition zones.

The system based on 4C Ocean Bottom Nodes which are controlled by the system’s lab containers.

Designed for offshore seismic exploration and regional studies.

CRAB Composition

Ocean Bottom Nodes

Ocean Bottom Node - operation in any orientation

Operation in any orientation at the seabed

Ocean Bottom Node - autonomous operation during 45 days

Autonomous operation during 45 days

Ocean Bottom Node - battery recharging time

Battery recharging time is 24 hours

Ocean Bottom Nodes - CRAB
Ocean Bottom Node - diameter

Diameter 245 mm

Ocean Bottom Node - height

Height 132 mm

Ocean Bottom Node - weight

Weight in air 12 kg

CRAB Specifications

Ocean Bottom Nodes

Electric technical specifications

4 channels
Orthogonal oriented Geophones: BH-20MT OMNI / GS-ONE OMNI
24 bit, delta-sigma with sample interval 0.25, 0.5, 1, 2, 4 ms
0, 6, 12, 18, 24, 30, 36 dB
Max input signal
1.8 V (rms)
Equivalent input noise
0.08 – 3 μV (rms)
Gain accuracy
≤ 1%
Instant dynamic range
126 dB at 0 dB gain
Flash memory
32 GB
Power autonomy
45 days

Geophone electric technical specifications

Natural frequency
15 Hz
Distortion (in any orientation)
< 0.2%
Coil resistance with shunt resistor 7.5 kΩ
1450 Ω
Open loop sensitivity
69,2 V/m/s
Sensitivity at 70% Damping
15 V/m/s

Hydrophone electric technical specifications

(at temperature 25°C, pressure 1 atm)
≥ 9000pF
6 V/Bar

Lab container


  • Charging batteries of the Ocean Bottom Nodes
  • Controlling the Ocean Bottom Nodes
  • Downloading recorded data from the Ocean Bottom Nodes
Lab container - CRAB


  • Up to 400 Ocean Bottom Nodes
  • Can be powered by different supply source (220V, 380V, 440V)

CRAB System Features

CRAB Ocean Bottom Seismic System - operated onshore or at depth

Can be operated onshore
or at depth up to 500 meters

CRAB Ocean Bottom Seismic System - Repreparation time is 24 hours max

Repreparation time
is 24 hours max.

CRAB Ocean Bottom Seismic System - Operating temperature from -10° to +50° C

Operating temperature
from -10° to +50° C


Marine Technical Center Limited Liability Company

+7 812 339-94-84​​

Dvinskaja st., 14A, space 1-n, office 70,
St. Petersburg, Russia, 198035

We will contact you within 1 working day!