SERCEL  SYNTRAK 960-24™  System

The debut of the newly released SYNTRAK 960-24™ in 1997 introduced breakthrough technology that increases system capability. The new generation recording system was the first of its kind on the market, capable of recording from up to 16 streamers and 960 channels.
Sercel's advanced Multiple Streamer Telemetry System (MSTS) allows the largest number of towed arrays and channels of any marine system in the industry, and ancillary products unique to SYNTRAK® extend operator control, streamline system management, increase efficiency, and expedite data collection.

Control Modules

The Multiple Streamer Telemetry Processor (MSTP) acts as an interface between the digital streamers and the recording system. Up to eight MSTP chassis can be operated simultaneously. The MSTP controls and analyzes streamer and module diagnostics and displays them on a high-resolution monitor. Built-in QC capabilities allow daily, weekly, and monthly tests to be pre-programmed and automatically run.

The Multiple Streamer Recording System (MSRS) houses all of the hardware for collecting and recording data. The System receives MSTP data, creates headers, and formats seismic data, which it writes to tape for processing. The system allows data to be plotted in real time on two plotters simultaneously. Data may also be plotted from tape in the playback mode. Recording functions include: data collection, tape, plot, observers log, reproduction, and off-line QC. A second MSRS allows real-time tape copying and off-line tape copy as well as dual recording.

Peripheral Equipment

The GCS90™ Gun Controller System provides a new realm of advantages to the operator. It simplifies calibration of the source arrays, digitized information, and allows sources to be displayed in several ways to expand the operators overall view of system performance. Precise digitization of the source signatures allows the peak and zero crossing zones to be reliably windowed to filter out precursor spikes or source firing crossfeed.
The modular design and digital processing allow for specialty applications, such as 2-boat or vertical seismic profiling (VSP) acquisition. The systems compact size minimizes rack space requirements, and its flexible architecture makes expanding its capabilities simple.

The SPS90 Solenoid Power Supply provides 16 channels of high voltage suitable for firing various energy sources. The power supply unit is powered by either 110 Vac or 220 Vac. Standard voltage settings can be supplied, and optional voltages are available. A safety feature allows the SPS90 to be disabled for emergencies.
The Gun Depth Transducer System provides accurate and reliable depth information for up to 32 gun transducers. Mounted close to the energy source, the 2-wire frequency modulated devices continuously report depth to the boat.

The SYNTRAK Diagnostic Unit (SDU) is a miniature stand-alone product that tests cables and streamer modules independently of the Multiple Streamer Recording System (MSRS). Designed for use in the field, the SDU runs the same tests as the MSRS, including functional tests and parametric analysis to evaluate noise, distortion, and signal amplitude, which means QC levels are upheld with the SDU while the MSRS is free for recording. This versatile unit can be used with a number of software packages, which can be specified by the client.

Multi-Vessel Timing and Data Synchronizer (MTDS) was designed originally for use in OBC surveys and provides autonomous timing synchronization for the seismic source and the recorder. The MTDS contains two complete radio subsystems that provide time synchronization accurate to 50nS. The radio systems are synthesized and allow flexibility of operating frequency, which can be changed without changing crystals. The MTDS has 8 event timers, as well as 8 serial interfaces that allow bi-directional information transfer.

Digital Streamer

Sercel's standard digital streamer is designed for a maximum working length of 12 km and has a breaking strength of 10,000 kg. The key to cost-effective handling of towed arrays is reliable and trouble-free handling. The RDA (Reduced Diameter Array) design provides increased crush strength in the spacers and allows the streamer to survive greater physical abuse in the field, while rounded components reduce skin damage during general use. A new hydrophone virtually eliminates sensitivity hysteresis in depths down to 100 m, and a unique flow-through oil valve prevents total fluid loss if a compartment becomes damaged.

The 24-bit Data Acquisition Module (DAM) utilizes the advanced technology of hybrid circuit boards. The module offers extended resolution, making it possible to record extremely small-amplitude signals even in the presence of high noise levels. Delta-Sigma analog-to-digital conversion and extensive use of Digital Signal Processing (DSP) technology allow digital filtering and signal processing functions to be carried out in the module. This same DSP technology also allows implementation of correlation and noise reduction algorithms. Preamplifier gains of 12, 24, 36, and 48 dB may be selected independently for each channel within each module. High linearity and ultra low distortion, which ensure enhanced recording fidelity at all signal levels, also result from this advanced technology.
The 24-Bit Module allows the SYNTRAK® system to record up to 12 channels per module from up to 16 towed arrays. With a single recording system, data can be gathered from up to 960 channels per streamer (over 15,000 channels with 16 streamers deployed). Additionally, the use of low-power circuitry allows the system to run continuously, whether it is on the reel or deployed for operation. A 60% reduction in module size is another advantage of this technology, which like the smaller RDA streamer, creates less drag for the system..

The Tail Buoy Power Module lies between the last active streamer section and the tail buoy and is controlled via the System Controller in the MSTS. The module supplies power to the tail buoy and can be activated or deactivated during streamer initialization and while on-line in Record Mode.

The Streamer Tension Unit (STU) manages streamer deployment, retrieval, operation, and maintenance. Powered from the streamer, the STU continuously measures the tensile load on the streamer and communicates that information shot-by-shot to an onboard recording unit. Operators use the information gathered by the STU to reduce risk during data collection, to protect in-water assets, and to optimize the time invested in the data collection process.

The Streamer Communication Unit (SCU) boosts bird communication signal levels to enable a signal to travel to any cable length at 3-km intervals without degrading even in the presence of leakage. The SCU is compatible with any compass/bird acoustics systems today on the market. A special battery backup keeps the SCU working even when power to the main streamer is interrupted.

The Heavy Duty Stretch Section made its debut at the end of 1997. This ruggedized section was designed for added strength near the connectors, where bending loads are the highest. The solution was to design these section ends using vectran to increase fatigue resistance in this critical area.

The Radial Stretch section offers the same amount of vibration attenuation as standard marine stretch sections, but in lengths that are half as long. The Radial Stretchs greatest advantage stems from its unique construction, which employs resilient materials that make the product rugged and extend its life in the field. More solid construction results in less mechanical damage and less incidence of failure under rough conditions.

The Fiber Optic Tow Leader uses optical fibers for telemetry transmission with optical-to-electrical converters built into the connectors on each end. The electrical telemetry signal arrives at the lead-in and is converted to light, travels through the Tow Leader, then is converted back to an electrical signal to return to the boat. The converters make the Tow Leader compatible with the rest of the SYNTRAK system and allow the fiber optic advantage of data transmission over much greater lengths without signal loss. Fiber-optics also reduces the diameter of the Tow Leader, which in turn reduces drag. The Fiber Optic Tow Leader has a breaking strength of 100,000 lbs.

Sercel Solid Cable (SSC) is the solid streamer compatible with both Syntrak telemetry schemes (Fiber Optic/Twin Axial).