SplitMultiSeis technology was developed in 2014 by “SPLIT” company. The main goal was to create an acquisition technology that could be used to obtain data suitable for identifying geological hazards. These include landslides, near-surface gas, frozen rocks, faults and other geological features that can be dangerous when installing drilling platforms and other engineering facilities at sea. Geological hazards are located in a depth range of 5 to 500 m, can be complex and can be distinguished by dynamic anomalies (such as gas and permafrost).
SplitMultiSeis is a two-level system. Acoustic profiling runs in a three-frequency range. The system consists of:
- Conventional system (standard seismic refraction survey)
Acoustic air gun – source with a 96-channel streamer – receiver – High-resolution seismic (HRS) – the central frequency of the signal is about 200 Hz.
- Deep tow system. Sparker source with registration of buried 16-32 channel streamer. – Very high resolution seismic (VHRS) – the central frequency of the signal is about 350-500 Hz.
- Parametric subbottom profiler – ultra high resolution seismic (UHRS) – the center frequency of the signal is 8 kHz and 100 kHz.
- The full range of works assumes that five different types of geophysical and hydrographic methods are carried out simultaneously (in one pass of the vessel), namely:
- bathymetric survey with multibeam echosounder (MBE);
- side-scan sonar;
- ultra high resolution seismic survey (UHRS), dual frequency mode;
- very high resolution seismic, deep tow mode (UHRS);
- high resolution seismic survey (HRS).
Navigation support of all types of work is also carried out.
The presence of a deep tow system allows obtaining data without interference with the satellite wave, which improves the results and reliability of dynamic analysis. The acquisition of data with different frequency ranges makes a comprehensive interpretation possible and also increases the efficiency of mapping objects in a wide range of depths.
SplitMultiSeis method parameters
|HRS||Source point||48-192 channels
Channel interval 3.125-6.26 m
Length 150-1500 m
|VHRS (tow system optional)||Sparker||16-24 channels
Channel interval 2-3.135 m
Length 30-72 m
|UHRS||Piezoceramic transducer||2-16 kHz|
SplitMultiSeis hardware and software complex
The complex has a number of advantages that provide maximum efficiency and economical use of its operation time.It meets the safety and environmental protection requirements and corresponds to the modern tasks of marine seismic exploration.
The complex includes:
- Electric and pneumatic sources of the acoustic signal
- Energy storage capacity of up to 5 kJ
- Receiving antennas-analog streamers, 1-24 channels with intervals of 1-3, 125 m
- SplitMultiSeis 64/24 b seismic station used as the data collection system
- Software for data collection and operational quality control of the obtained material
- Hardware synchronization devices
- Devices for descending, lifting and towing equipment
Elements of the complex are unified, it is possible to add sources and seismic stations of the company “SPLIT” and other manufacturers.