Fig. 1. The Atlantic Explorer was the industry’s second sixstreamer ship and the first vessel to offer full onboard seismic data processing. It is now operational with Geostreamer technology.
Photo: GS.
New streamer technology improves resolution of seismic data
Keith Forward reports on how the resolution of seismic data is being improved by the use of velocity sensors alongside pressure sensors.
Keith Forward berichtet, wie die Auflösung von seismischen Daten durch den Einsatz von Geschwindigkeitsmessern zusätzlich zu Drucksensoren verbessert werden kann.
Keith Forward explica cómo el uso conjunto de sensores de velocidad y sensores de presión está mejorando la resolución de los datos sísmicos.
P
etroleum Geo-Services (PGS) has developed a new streamer technology to improve the resolution of seismic
data by using velocity sensors alongside conventional pressure sensors. Te sensors are part of PGS’ Geostreamer technology, the result of an extensive development programme over the past few years. Te idea of using velocity sensors is not new, it has been used in ocean bottom seismic for many years, but PGS has managed to solve the engineering problems that have prevented implementation of the technique for marine acquisition until now. PGS has so far captured more than 90 000 line kms of 2D GeoStreamer data, and 9000 square kms of 3D data has been recorded in many different basins and geological settings around the world in more than different countries. Te company believes the technology will be standard for the industry in a few years, resulting in significantly better seismic data and the ability to record in harsher environments and weather conditions, improving operational efficiency. “Te GeoStreamer will change the game in our industry,” said Jon Erik Reinhardsen,
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President & CEO of PGS. “In the future all towed seismic acquisition will use dual sensors. Oil is getting harder to find. For our clients it means more and better information from the reservoir.”
Te company plans to accelerate the roll
out of GeoStreamer earlier than originally planned. Te successful results of the new streamer have resulted in a decision to convert half of the 3D fleet to GeoStreamer by the end of 2010.
Two sensors are better than one Te problem with conventional single sensor marine seismic is that at some frequencies the seismic response from the subsurface is masked by reflected seismic waves that have bounced off the ocean surface. Tis ghost reflection adds noise to the resulting seismic image making interpretation more difficult. Geostreamer works by incorporating
a particle velocity sensor alongside the conventional hydrophone pressure sensors. Te velocity sensor complements the pressure sensor as the peaks in the velocity spectrum match the troughs in the pressure spectrum, enabling the missing frequencies to be filled in.
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