TGS-NOPEC Geophysical Company Provides FY 2004 Update

Based on preliminary reporting from operating units, TGS management now expects Net Revenues for the Fourth Quarter of 2004 to be approximately USD 58 million, bringing estimated Net Revenues for the full year 2004 to approximately USD 171 million. As a result, full year over year growth from 2003 is now expected to be approximately 25%; significantly above management's previously expressed expectations of 16-17%(including Nu-Tec).

The full 4th Quarter earnings release is scheduled for February 10th, 2005. Management will also issue guidance for 2005 at that time.