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ODIM MVP™ MVP Support of Seismic Surveying The ODIM MVP300 is one of a family of Moving Vessel Profiler™ products that uses a computer-controlled smart winch and deployment system that allows an instrumented Free Fall Fish to be deployed while a survey vessel is underway. The system is automated and can be controlled by computer without the requirement for personnel on deck. The MVP300, for example, will allow the collection of water column information (e.g. SV&P, CTD) to depths of 1300 metres while the vessel is traveling at 6 knots and as deep as 2000 metres at 3 knots.
![]() Seismic operations can benefit from the MVP’s underway data collection operation by collecting the CTD profiles on a continuous basis. In addition, the profiles can be obtained in exactly the same time and place as the ongoing seismic operations. As an alternative, the MVP can be installed on the chase boat if the operator desires.
![]() Accurate knowledge of the water velocity, as a function of depth, at the time of data acquisition efficiently facilitates the removal of discontinuities in multibeam and seismic data caused by velocity variations in the water column. This is particularly important in deeper water and where velocity values are expected to vary over time. This relevant to 3D and 4D seismic operations.
![]() Normal Seismic Operations
Figure 1 provides a realistic view of the complex conditions that exist during normal seismic survey operations. As an example, during ODIM MVP sea trials in the summer of 2007, the Fugro Geo Atlantic was simultaneously towing 10 seismic streamers (upper group of cables) and six gun arrays (lower group of cable). With the implementation of the ODIM MVP (upper deck circled) there existed yet another cable.![]() The operation of the ODIM MVP involves the continuous towing and repetitive free fall casting of Single Sensor Free Fall Fish (SSFFF). Figure 2 illustrates this process.
Figure 2: Trajectory of ODIM MVP™ SSFFF ![]() The objective with the installation of the ODIM MVP is to obtain water column sound velocity data with the SSFFF during seismic survey operation without interfering with the complex cable configuration off the stern of the survey vessel as well as the submerged seismic cables and gun array.
![]() ODIM MVP™ Installation A typical installation of the MVP technology onboard a seismic survey vessel was illustrated in Figure 1.
![]() Figure 3 provides an aerial view of the position of the seismic gun array, survey vessel, and the ODIM MVP with the trailing SSFFF.
![]() ![]() Figure 3: Aerial view of ODIM MVP and complex seismic cabling ![]() The following animation illustrates the activity of the ODIM MVP free fall fish as the survey vessel conducts its operations. Before the start of a sound velocity profile, the tow fish is towed only a few meters from the stern of the vessel and travels at a distance of 2-3 metres below the surface.
![]() ODIM FFCPT™ for Electromagnetic Resistivity Measurement
The FFCPT offers a low-cost, rapid, reliable method for obtaining information on the engineering and sedimentological characteristics of sediment at the seafloor. The ODIM Free Fall Cone Penetrometer (ODIM FFCPT) is an added value technology that has been well proven for the the collection of geotechnical and geophysical data during route location surveys for seabed cable and pipeline installations, for bottom classification and acoustic ground-truthing, as well as for mine countermeasures and geo-environmental studies.![]() The following ANIMATION illustrates how the ODIM FFCPT works in conjunction with the ODIM MVP while a vessel is under way.
![]() ![]() ODIM is now progressing with the implementation of resisitivity measurement of the sediment through the use of the FFCPT. This technology will be brought to the market in the near future.
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