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 'down- stream' in quantitites extracted is investigated. We also note that increasing returns to scale in exploration can introduce an unstable solution with a corner solution the presumed stable equilibrium.