Strategic considerations of exploration and extraction are investigated in a two player, two period, two stage perfect equilibrium framework. Relative to two "plant" monopoly, the duopolists explore more and extract more period by period. A mixed game in which there is co-operation "upstream" in exploration and Cournot competition "downstream" in quantities extracted is investigated. We also note that increasing returns to scale in exploration can introduce an unstable interior solution with a corner solution the presumed stable equilibrium.