Press Releases

TGS expands 3D multi-client seismic data library in the Barents Sea

ASKER, NORWAY (24 May 2011) - TGS commences the acquisition of multi-client 3D seismic data in the Hoop Fault Complex area of the Barents Sea.  This survey is an extension of the previously announced Hoop Fault Complex survey and will add 1,800 km2 to the existing data in the area.  Approximately 500 km2 of the survey are infill in the Northern area of the 2009 survey and the remaining 1,300 km2 are an extension to the east of the 2009 survey area.  TGS is very pleased with the historical client response to the coverage in this new exploration province.  Blocks have been awarded in the survey area during the last two rounds and with the 2011 acquisition, TGS will be able to provide extended coverage for future rounds.

The M/V Polar Duke towing 10 x 6,000 m streamers with 75 m separation will acquire the 2011 survey.  Data processing will be performed by TGS and will be available to clients in Q4 2011.  The survey is supported by industry funding.

HFC11

About TGS

TGS provides multi-client geoscience data to oil and gas Exploration and Production companies worldwide. In addition to extensive global geophysical and geological data libraries that include multi-client seismic data, magnetic and gravity data, digital well logs, production data and directional surveys, TGS also offers advanced processing and imaging services, interpretation products, and data integration solutions.

All statements in this press release other than statements of historical fact are forward-looking statements, which are subject to a number of risks, uncertainties and assumptions that are difficult to predict, and are based upon assumptions as to future events that may not prove accurate. These factors include TGS' reliance on a cyclical industry and principal customers, TGS' ability to continue to expand markets for licensing of data, and TGS' ability to acquire and process data product at costs commensurate with profitability. Actual results may differ materially from those expected or projected in the forward-looking statements. TGS undertakes no responsibility or obligation to update or alter forward-looking statements for any reason.

Sven Børre Larsen

Sven Børre Larsen

Chief Financial Officer

Tel: +47 90 94 36 73

Ellen Munkvold

Ellen Munkvold

IR Coordinator

Tel: +47 97 76 26 25