Offshore's 1998 survey of seismic vessels
includes 29 companies, 162 vessels
This year's survey reveals two dominant themes continuing from the 1997 survey:
- The industry continues to compensate for the increased vessel demand that began in early 1997. A total of 41 vessels were either built, converted, or scheduled for delivery in 1997 and 1998.
- New vessels are decidely larger and definitely contain much more towing and processing equipment. The ability to tow larger arrays with more footprint was paramount, but also on-board processing and the ability to provide customers with an early image of processing results.
1998 survey resultsThe 1998 survey indicates a host of new trends:
- 3D acquisition: Last year, Offshore Magazine reported a total of about 80 vessels had been equipped with 3D acquisition capability. In this year's survey, 123 vessels have 3D acquisition capabilities. Another 89 vessels possess 4D capabilities.
Of the vessels surveyed in 1997, 95 performed 3D acquisition tasks, and 18 performed 4D. This increase in 3D capability illustrates the growth in regional and proprietary 3D seismic acquisition, plus the growth in 4D surveys. This also shows that the seismic industry has responded to the operators' acceptance of 3D acquisition techniques.
- Deepwater: Another growing trend is operations in deepwater. A total of 120 vessels are equipped with the technical capability to operate in deepwater - 42 more vessels than last year's report. This illustrates the need for seismic vessels, and data, to evaluate deepwater fields.
- Satellite communications: The 1998 survey also indicates a trend to satellite communications. Satellite communications of collected data is shortening the delivery time of final products to the customer. Over 100 of the vessels possess satellite transmission abilities. The average delivery time is 1-45 days for most vessels.
- Streamer capacity: Vessels are beginning to use smaller diameter streamers to reduce the towing weight. This allows for a larger number of streamers and larger arrays. New vessels are also being equipped with greater streamer towing capacity for wider and longer arrays for exploration 3D surveys.
- Minor trends: The expansion of onboard processing to enhance quality control, processing navigational data for vessel location and footprint configuration, and preprocessing of seismic data before sending by satellite to land are also becoming more important for vessel operations. A total of 120 vessels use navigational data for onboard processing, 132 use quality control, and 97 use full data processing.
Survey explanation:Several categories have been re-titled or added to the 1998 survey to better represent the capabilities of the world's fleet. The 1997 survey featured "Source array configuration as rigged". This was replaced this year by "Maximum towable footprint." This category has been broken down into the number of cables, by length and by width. "Onboard data compression system" has also been deleted.
Featured in this year's survey are vessel year rigged or converted, vessel measurements, streamer configurations, streamer information, 1997 source array configuration, 1997 acquisition experience, technical capabilities, onboard processing, final primary recording media, and delivery time.
Unless indicated by an asterisk, all data presented was provided by the companies listed. Limited information is provided on vessels belonging to companies with unknown addresses and those that did not respond to the survey.
Copyright 1998 Oil & Gas Journal. All Rights Reserved.