Horizon Oil Limited is engaged in petroleum exploration, development and production. The Company's segments include New Zealand development, New Zealand exploration, China exploration and development, PNG exploration and development, and All other segments. The New Zealand development segment produces crude oil from the Maari/Manaia fields, located offshore New Zealand. The New Zealand exploration segment is involved in the exploration and evaluation of hydrocarbons in the offshore permit area, PEP 51313. The China exploration and development segment is involved in the development and production of crude oil from the Block 22/12-WZ 6-12 and WZ 12-8W oil field development, and the exploration and evaluation of hydrocarbons within Block 22-12. The PNG exploration and development segment is involved in the Stanley condensate/gas development, and the exploration and evaluation of hydrocarbons in over five onshore permit areas, such as PRL 21, PPL 259, PPL 372, PPL 373 and PPL 430.