Industry revealed advances to speed and simplify the acquisition and storage of large seismic survey data sets.
Western Geophysical, Houston, and Thomson Marconi Sonar Pty. Ltd., Sydney, Australia, for the first time incorporated marine seismic sensors into new streamers made of a solid, flexible material they said is a major improvement over current oil-filled plastic cables.
Meanwhile, Shell Oil Co. is installing seismic data compression technology that will save interpretation time and reduce storage requirements, especially for very large 3D seismic data sets. It plans to license and market its application of the technology, developed jointly with Houston Advanced Research Center, during the next few months.
The HARC-C technology is built on a set of mathematical principles called wavelet theory. Image attributes are described mathematically in terms of frequency, energy, and timing blocks, managing the task in real time. The technology, which runs on a workstation and requires no special hardware, solves the problem of file size by coding an image in a form easily stored and shipped, Shell said.
The proprietary solid streamer will cost less, require less maintenance, and last longer, Western-Thomson said.
Marine streamers are the costliest and most critical components aboard modern seismic vessels. Main advantages of the new cable are its strength and reliability, which enable it to be retracted back onboard while the vessel is still moving forward.
Early tests indicated the new streamer has a better stability in high sea states where traditional streamer operations had to be shut down because the "noise" environment affected data quality. The buoyancy of the new streamers makes them fully recoverable at sea.
Western has installed the streamers on one vessel and plans to add them to others as it replaces old streamers as they wear out.
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