TGS’ Elected Members

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    Henry H. Hamilton III, Chairman 

    Mr. Hamilton served as CEO of TGS from 1995 through June 2009. He started his career as a Geophysicist with Shell Offshore (1981-1987) before he became employed by Schlumberger (1987-1995), where he ultimately held the position of VP and General Manager for all seismic product lines in North and South America.

    Mr. Hamilton joined TGS as its CEO in 1995 and remained in the position following the 1998 merger with NOPEC International. He also serves on the Board of Odfjell Drilling and for two non-profit organizations: the University of North Carolina College of Arts and Sciences Foundation and Defy Ventures. Mr. Hamilton was first elected as a director in 1998 and as Chairman in 2009.                    


    A.WenchieWenche Agerup, Director   

    Ms. Agerup is EVP Corporate Affairs and General Counsel Executive of Telenor ASA. From 1997 to 2010, Ms. Agerup held various leading positions within Norsk Hydro ASA, including Plant Manager at Årdal Metal Plant in Norway and Project Director in Hydro UMC Joint Venture in Australia.

    From 2010 to 2015, Ms. Agerup was Executive Vice President, Corporate Staffs & General Counsel of Norsk Hydro and member of the Corporate Management Board, reporting to the Chief Executive Officer. Ms. Agerup serves as a board member of Statoil. She was first elected as a director in 2015.


    E.GriegElisabeth Grieg, Director 

    Ms. Grieg is currently CEO of Grieg International AS, co-owner of the Grieg Group and a member of the founding family. Ms. Grieg serves on the board of several of the Grieg Group companies. She has also been a board member of many prominent Scandinavian companies, such as Statoil, Norsk Hydro and Nordea AB, as well as a member of the corporate assembly of Orkla ASA.

    Ms. Grieg has chaired the board of GIEK (Norwegian Guarantee Institute for Export Credits) and been the President of the Norwegian Shipowners’ Association. She was first elected as a director in 2015.


    Nils Petter Dyvik, Director 

    Mr. Dyvik has served in various capacities for Wilh Wilhemsen, a global maritime company, most recently as Group CFO from 2007 to 2016. From 2002 to 2007, he served as CEO of Wallenius Wilhelmsen, from 1999 to 2002, as Deputy CEO of Wilh Wilhelmsen, and from 1996 to 1999, as Deputy CEO of Wilhelmsen Lines AS. Prior to joining Wilh Wilhemsen, he served as CEO and Deputy CEO for Norwegian American Line from 1988 to 1996, and worked with Kreditkassen (Nordea) from 1986 to 1988, L.M. Skaugen from 1980 to 1986, and Saga Petrokjemi from 1979 to 1980. Mr. Dyvik has extensive board experience, and currently serves as the Chair of NorSea Group and Wilhelmsen Ferd Offshore AS and as a member of the Board for The Maritime Rescue School.  He was first elected as a Director of TGS in 2017.


    Mark Leonard, Director 

    Mr. Leonard is currently the President of Leonard Exploration, Inc. He retired in 2007 from Shell Oil Company after 28 years of service. During his tenure at Shell, Mr. Leonard held a number of executive positions including Director of New Business Development in Russia/CIS, Director of Shell Deepwater Services, Director of Shell E&P International Ventures and Chief Geophysicist for Gulf of Mexico. He was first elected as a director in 2009.


    Tor Magne Lønnum, Director 

    Mr. Lønnum is currently Chief Financial Officer of Aimia Inc. Prior to joining Aimia, he was Group CFO in Tryg AS and Tryg Forsikring AS from 2011 to 2016. He has also previously held the positions of CFO in Skipper Electronics AS, Accountant in Samarbeidende Revisorer AS, Manager in KPMG, Group CFO and Group Director in Gjensidige NOR Insurance, Deputy CEO and Group CFO in Gjensidige Forsikring ASA. He was first elected as a director in 2013.


    Vicki Messer, Director 

    Ms. Messer is currently an independent consultant. She has 32 years of geophysical industry experience in various executive, management and supervisory positions for CGG Veritas, Veritas DGC, Halliburton Energy Services/Halliburton Geophysical, and Geophysical Services Inc. She was first elected as a director in 2011.


    Torstein Sanness, Director 

    Mr. Sanness served as the Chairman of Lundin Norway from April 2015 to March 2017, when he moved to the board of International Petroleum Corp., a Lundin Group company. He previously served as the Managing Director of Lundin Norway from 2004 to 2015. From 2000 to 2004, he served as Managing Director of Det Norske Oljeselskap AS, and from 1972 to 2000, he served in various capacities for Saga Petroleum, working primarily in the exploration and development of Saga’s oil and gas interests globally.

    Mr. Sanness serves as a board member for Panoro Energy ASA. He was first elected as a director in 2016.