Press Releases

TGS commences high density multi-client 3D data acquisition for Moray Firth survey

ASKER, NORWAY (23 June 2010) - TGS announces the commencement of a 1650 km2 high density multi-client 3D seismic survey located in the outer part of Moray Firth off the Northeast coast of Scotland.

The survey covers open as well as held acreage and is located in an area proven to be particularly prolific for hydrocarbon exploration. This has been confirmed by recent discoveries including Golden Eagle, Hobby, Pink and Blackbird.

TGS has contracted the Polarcus Nadia vessel to acquire the Moray Firth 3D survey. The Nadia will deploy 8 X 5000m of streamers for the acquisition and the project is expected to complete in late Q3-2010. The data processing will be done at TGS' imaging center in Bedford, England.

Data from the Moray Firth survey will be available for customers from Q1-2011. The Moray Firth high density multi-client 3D survey is supported by industry funding.

Moray-Firth

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