OBS Ocean Bottom Seismometer
Ocean bottom seismometer (OBS) is a kind of seismic observation system that place geophone directly at sea bottom. In marine geophysical investigation and research, OBS can be used to observe both artificial and natural seismic profile. The observation results can be used to study the velocity structure of marine earth crust and mantle and kinetic characteristics of subduction zone, trench and trough evolution. The results can also be used to study the seismic tomography of natural earthquakes, seismicity and earthquake prediction etc.
ApplicationOBS is a kind of seismic data collection system placed at ocean bottom. It can be used to record natural earthquakes and investigate artificial ones. OBS are widely used in oil exploration and investigation of deep structure of the earth etc.
Narrowband long-term 4-channel OBS | OBS Portable short-term 4-channel OBS | Short-term 4-channel OBS | |||
Weight | Instrument | 90 kg | 25Kg | 44 kg | |
Seismic anchor | 25 kg | 10 ~ 15 kg | 20 ~ 25 kg | ||
Volume | Instrument | 600×600×1200 | 400x400x600 | 600×600×700 | |
Seismic anchor included | 900×900×1500 | 700x700x800 | 900×900×1000 | ||
Deployment depth limit | 6000m, 9000m,12000m | 6000m | 6000 m, 9000m | ||
Channels | 4 (3 for velocity geophone and 1 for hydrophone) | ||||
Working time | 10 ~ 15 months | 2 months | 10 months | ||
Max recycling time | 24 months | 6 months | 15 months | ||
Geophone | Bandwidth | 60 s ~ 50 Hz, capacitance transduce seismometer(60 s ~ 50 Hz 120 s, 60 s and 30 s ~ 50Hz optional | 1 Hz ~ 200 Hz 0.1 Hz, 2 Hz , 4.5Hz~ 200 Hz optional | 0.1 Hz ~ 100 Hz optional; 0.1 Hz, 0.2 Hz, 0.5 Hz, 1 Hz, 2 Hz ~ 100 Hz optional | |
Sensitivity | 100V/(M*S-1) | ||||
Hydrophone | Bandwidth | 0.01 Hz ~ 20k Hz or 2Hz~30kHz | |||
Sensitivity | -165 dB re: 1 V/uPa | ||||
Power consumption | 0.15 w | ||||
Dynamic range | >120dB | ||||
Sampling rate | 250, 100, 50 sps | 500, 250, 100sps | 500, 250, 100sps |
- There are three types of OBS: broadband, short-term and portable, to meet various operation requirements.
- OBS can collect 3 channels of seismic signal and 1 channels of hydraulic signal, with great resolution and consistency.
- There are three operation depths optional: 6000m, 9000m and 12000m.
- There are multiple frequency bandwidths available: 4.5Hz~300Hz, 1Hz~200Hz, 5s~150Hz, 10sHz~150Hz, 30s~150Hz, 60s~100Hz, 120s~50Hz etc.
- According to different operation requirements, continuous operation duration can be 2~15 months and maximum retrieve period can be 6~24 months.