Nick Shepherd

Nick Shepherd is an oil and gas lawyer with 25 years of industry experience in a number of senior in-house legal roles.  

Nick joined Zennor in July 2017, having been Regional General Counsel at Tullow Oil plc, where he was responsible for the legal team in the London Head Office. Previously Nick held senior legal roles in Paladin Resources plc, BHP Billiton Limited and Premier Oil plc and has also advised a large number of other upstream independents. 

During his time at Zennor, Nick has been instrumental in securing the legal structures that underpin the Finlaggan development, as well as helping deliver the Britannia/Mitsui transaction.


Marilyn Merryweather

Marilyn Merryweather

Marilyn Merryweather  is geophysicist with more experience than any other member of the Zennor team.  Another ARCO veteran she has been instrumental in c.20 discoveries in UK Central and Southern North Sea, such as Tyne West, Waveney, Hawksley, Glenelg, Murdock K, Munro, Polecat, Opal, Vanquish and Eos.

Following the acquisition of ARCO, Marilyn worked for BP, Tullow and EOG Resources and in 2006 joined the technical team at Zennor helping them to grow and mature the Company’s UK asset base through successful license round applications.

Marilyn’s most recent efforts at Zennor have focused on the identification and evaluation of potential infill locations in the producing fields acquired from First Oil in 2016.

Peter O’Mara

Peter O’Mara is a highly experienced geologist with knowledge across the upstream value chain gleaned from over 25 years with  ARCO, Ruhrgas, EOG Resources and Zennor.

Peter served as the main technical partner in multiple UK North Sea JV’s and was responsible for drilling, reservoir engineering, geoscience, subsurface efforts, development well planning and initial start-up of a number of fields and discoveries: Trent & Tyne’ CMS3, Elgin/Franklin, Scoter/Merganser, Conwy, Polecat, Arthur, Valkyrie and Columbus.

At Zennor, Peter has been responsible for the subsurface modelling of Finlaggan, through pre-appraisal and development phases including delivery of the subsurface element of the Field Development Plan.

David Beaghan

David Beaghan has over 30 years of oil and gas industry experience in planning and managing drilling operations. This includes UK and international exposure, onshore and offshore operations and periods supervising operations at the well site.

David has worked with a variety of operators ranging from large multinationals to small independents and was the Drilling Manager for the four offshore UK North Sea operated wells drilled by Zennor North Sea Ltd in the period 2012-16.

David’s leadership skills and eye for detail has made his step up to Operations Director appear seamless at Zennor, where he is responsible for all aspects of the Finlaggan development project.

Graham Cooper

Graham Cooper

Graham Cooper is a geologist with over 35 years of industry experience, of which the last 20 have been spent in commercial and business development roles. A large proportion of that time was spent in senior commercial roles in Shell, including Vice President–Commercial for Shell International Global Exploration and Head of the Commercial Academy for the entire Shell Group.

Graham joined Zennor in January 2016 from EnQuest plc where, as Head of Business Development since 2011, he was responsible for delivering a large number of North Sea focused acquisitions. 

Since joining Zennor, Graham has, amongst other transactions, delivered the First Oil acquisition in early 2016 and the Britannia acquisition from Mitsui, which was signed in September 2018.