TGS Commences New Multi-Client 3D Wide Azimuth Survey in Gulf of Mexico

HOUSTON, TX--(Marketwire - May 23, 2012) - TGS has commenced acquisition of a 3D multi-client wide azimuth (WAZ) survey covering over 3,500 km² in the Gulf of Mexico.

The survey, Independence WAZ 3D, continues TGS' Constitution group of WAZ projects, including Freedom, Liberty and Justice, which together total 27,622 km² in the deep water Gulf of Mexico.

"We are pleased to extend our expansive WAZ coverage in the Gulf of Mexico. This survey, along with the other WAZ surveys within TGS' Constitution group, will help provide our clients with a clearer image of the geologically complex substructure in the prolific Mississippi Canyon region. Industry support of the new survey indicates increasing interest to explore in the region," commented Rod Starr, Senior VP Western Hemisphere for TGS.

The new seismic data is being acquired by a four-vessel WAZ fleet. The data will be processed by TGS and preliminary products will be available to participating companies in Q4 2012 with a final processed product expected in 2013.

The survey is supported by industry funding.

Company summary
TGS-NOPEC Geophysical Company (TGS) provides multi-client geoscience data and services to oil and gas Exploration and Production companies around the globe. TGS' geophysical and geological data products include multi-client seismic libraries, permanent reservoir monitoring, magnetic and gravity data, the industry's largest global database of digital well logs and regional interpretive products. TGS also provides high-end depth imaging services to help resolve complex seismic imaging problems. 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).