TGS Commences 3D Multi-client Seismic Survey Offshore Liberia

ASKER, NORWAY (16 January 2013) - TGS has commenced acquisition of a 3D multi- client survey, Sunfish, which covers up to 7,800 km(2) of highly prospective acreage in the Harper Basin, offshore Liberia. "This survey provides excellent data coverage for the source prone, syn-rift and early post-rift sequences, in this highly prospective area offshore Liberia. TGS has been active in acquiring data over the West Africa Transform margin for the past decade and this survey demonstrates TGS' ongoing commitment to grow the seismic data library in Africa," commented Stein Ove Isaksen, Senior VP Eastern Hemisphere for TGS. TGS is chartering the 12 streamer Polarcus Asima for this survey.  The charter will last for approximately six months.  Data processing will be performed by TGS and will be available to clients in Q4 2013, prior to the Liberia 2013 Bid Round. The survey is supported by industry funding. Company summary TGS-NOPEC Geophysical Company (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, permanent reservoir monitoring and data integration solutions. For more information visit TGS online at www.tgs.com. Forward-looking statements and contact information 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 products 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. TGS-NOPEC Geophysical Company ASA is listed on the Oslo Stock Exchange (OSLO:TGS). For additional information about this press release please contact: Kristian Johansen Chief Financial Officer Tel: +47 47 60 33 34 Email: kristian.johansen@tgs.com Will Ashby Director Investor Relations and M&A Tel: +1 713 860 2184 Email: will.ashby@tgs.com Stein Ove Isaksen Senior VP Eastern Hemisphere Tel: +47 66 76 99 00 Email: SteinOve.Isaksen@tgs.com This information is subject of the disclosure requirements acc. to §5-12 vphl (Norwegian Securities Trading Act) This announcement is distributed by Thomson Reuters on behalf of Thomson Reuters clients. The owner of this announcement warrants that: (i) the releases contained herein are protected by copyright and other applicable laws; and (ii) they are solely responsible for the content, accuracy and originality of the information contained therein. Source: TGS via Thomson Reuters ONE [HUG#1670346]