Tullow Oil plc Annual Report 2011 - The Group

Notes to the Group financial statements continuedYear ended 31 December 2011Note 11. Intangible exploration and evaluation assetsAt 1 January 4,001.2 2,121.6 2,052.8Acquisition of subsidiaries 424.1 – –Additions 1,190.0 2,047.7 684.7Disposals – (6.2) –Amounts written off (120.6) (154.7) (82.7)Transfer to property, plant and equipment (note 12) – (7.0) (542.1)Currency translation adjustments (44.7) (0.2) 8.9At 31 December 5,450.0 4,001.2 2,121.6The amounts for intangible exploration and evaluation assets represent active exploration projects. These amounts will bewritten off to the income statement as exploration costs unless commercial reserves are established or the determinationprocess is not completed and there are no indications of impairment. The outcome of ongoing exploration, and thereforewhether the carrying value of exploration and evaluation assets will ultimately be recovered, is inherently uncertain.Included within 2011 additions is $128.8 million of capitalised interest (2010: $30.7 million, 2009: $17.5 million). The Group onlycapitalises interest in respect of intangible exploration and evaluation assets where it is considered that development is highlylikely and advanced appraisal and development is ongoing. Additions in 2010 include $1,450 million in relation to the acquisitionof a 50% stake in Blocks 1 and 3A in Uganda.2011$m2010$m2009$m134Tullow Oil plc 2011 Annual Report and Accounts