Both terrestrial radio links and satellite links are used to broadcast and receive Differential GPS data. The current C-nav DGPS network provides wide area positioning coverage over all the Nigerian coastal regions and Africa as a whole. All Nigerian offshore hydrocarbon producing concessions are currently covered by the Nigerian C-nav. System producing regions with positioning accuracies of two meters in dynamic real-time mode. The existing West African C-Nav network has been established to provide accurate, reliable and repeatable cost effective services to surface vessels and drilling rigs. The performance of the current positioning network is controlled 24hours a day from a fully manned network control center in South africa, ensuring a high quality positioning service.
Seismic Vessel Positioning
C-nav provides the seismic vessel operator with a 700-8000 km range navigation service. For 3D surveys advanced products, under continuous development enable the positions of the streamer tail buoys to be continuously monitored.
Personnel, positioning equipment, computers and advanced positioning software are available to position exploration drilling rigs precisely on to new locations. In addition, tracking systems have been developed for the positioning of anchor handling tugs and other ancillary vessels.
Dedicated site survey vessels equipped with high resolution multi-channel geophysical acquisition systems are rapidly mobilized and operated to check for the presence of shallow gas deposits and other hazards at proposed drilling sites. High quality mapping and interpretation services (including 3D) are available.
Positioning for VSP Surveys
A navigation package with unique software, which offers a flexible system, configured to suit VSP acquisition surveys.
FIELD DEVELOPMENT & PRODUCTION
We provide a center of expertise for the provision of a full range of survey services to support all phases of offshore construction projects;
Seabed and substrata studies are vital to the planning, design and construction phases of any offshore development. Vessels, personnel and equipment are provided to locate any potential engineering hazard such as structural faults, gas pockets, reefs and man-made obstructions.
All phases of the complete pipeline program including route reconnaissance studies, pipeline route surveys, and surveys during pipe lay operations and pipeline inspections are undertaken. Detailed studies using terrestrial and satellite positioning, echo sounders, side scan sonar, sub-bottom profilers and magnetometer equipments, as well as soil sampling are conducted prior to pipe lay operations. These surveys chart water depths and locate suitable sea floor characteristics for optimum pipeline route selection.
As-laid and as-trenched surveys are conducted using towed geophysical sensors or ROV’s equipped with sensors to measure pipe burial depths, scours and free spans.
Platform & Underwater Installations
We provide assistance with the installations of platforms, jacket sections and templates of offshore hydrocarbon provinces. We have custom designed software that integrates surface and sub-surface positioning data to generate graphics showing the position, yaw, pitch, roll and depth of the structure being lowered and leveling information when it is on the seabed.
FOR THE CIVIL ENGINEERING AND DREDGING INDUSTRIES
Near shore hydrographic, geotechnical and environmental surveys to support all aspects of civil engineering work, including port and harbor development, bridge tunnel construction, and dredging projects.
Advanced automated PC computer and swathe bathymetry systems are used to acquire and process data. Land surveys are also conducted in association with near shore surveys. These may extend into control and trigonometric surveys including satellite fixing techniques and astronomical observations.
Internal Pipe Work Inspection
Specialized apparatus for internal pipe work inspection of pipe works in oil refineries and storage depots, nuclear power plants, vertical drilling platform pipelines and drilling platforms legs are also carried out in accordance to specification and standard.
FOR THE MARINE CABLE INDUSTRY
A full range of services including desk studies, landing point coordination, analogue geophysical investigation, geotechnical sampling, precise terrestrial and satellite positioning and use of specialized investigative sensors such as proton magnetometer and gamma spectrometers.
Precise positioning systems, specialized navigation software and experienced personnel provide full support to cable installation contractors.
All information are captured using industry standard software like Trimble’s HYDRO allowing data to be processed and output in client compatible formats, suitable for CAD design and management systems.
Data can be structured according to the client organization’s specific requirements and organized to facilitate the addition of intelligent, attribute information, relating to each element.
System Engineering and Technical Support
Fem Associates Nig LTD has developed an extensive capability in providing field personnel and equipment to her overseas projects. Fully equipped workshops at all operational bases manned by experienced engineers ensure that all equipment is maintained and functions to specification prior to deployment on projects.
It is not the policy of FEM Associates to sub-contract any element of a project. Our preference is to undertake all works in-house ensuring full control over program and quality
Availability for Work
Fem Associates is available for work at the shortest notice of three days before mobilization including her present load and any future commitments.