"STING Mk.II"™ A new service offered by
Coastal Geoscience Research
STING is a self-contained, tethered probe with a streamlined body and a long (up to three metres), slender steel shaft protruding from the nose cone. The unit is released from a vessel so that it drops freely through the water, reaching terminal velocity, and impacts into the sea floor vertically with its calibrated shaft and foot. Internal microprocessor-based electronics record the deceleration as the shaft embeds itself into the layers of the bottom sediment. Since a typical seabed impact event lasts under a second, it is possible to commit multiple impacts to the built-in memory bank. Successive drops can be performed during a single deployment by simply raising the probe several metres off the bottom. After the unit is brought back to the surface the data is downloaded to a PC workstation. Sophisticated analysis software, included with the probe, determines various kinematic parameters for each impact event and computes an estimate of the seabed bearing strength.
Data acquisition can be initiated by water immersion or optionally by hydrostatic pressure level. The immersion (conductivity) switch starts the acquisition as soon as a pair of electrodes is shorted by the water. The conductivity trip point is menu driven and may be set for different salinity levels, including fresh water. Units equipped with the optional depth measurement system may be programmed to start the data logging process at a predetermined water depth, thus economizing memory usage. The depth measurements may be recorded alongside the acceleration data if so desired.
Applications for STING include...
•Sub-sea cable and pipeline route selection
•Sediment deposition determination
•Harbour surveys
•Environmental impact surveys
•Ground TRUTHING for sub bottom acoustic profiling systems
•Pre-dredging seabed assessment
•Selection of appropriate equipment and methods in salvage operations
The system consists of...
•Newton Gradiometer probe recording deceleration
•One-metre shaft segment with standard contact foot (shaft extensions and additional foot sizes available)
•Battery charger
•RS232 data download cable with sub-sea connector and serial port plug
•Communications and Data Analysis software
•Storage container suitable for shipping
Optional accessories include...•shaft extensions and couplers,
•various foot sizes for different sediment types,
•pressure triggering
•and an optional hand-operated winch system for line handling and recovery.©2002-2006 Coastal Geoscience Research Corporation. All rights reserved.