Oil and gas company Savannah Petroleum has successfully placed a total of 61.7m shares at 38p per share, raising gross proceeds of around $36m to finance the acquisition of additional acreage in Niger.The placing shares issued represent approximately 47% of the company's existing issued share capital and the shares are to be issued in two tranches.A first tranche of just under 43.8m shares will be issued immediately following settlement on 13 July 2015, raising gross proceeds of approximately $26m.A second tranche of 17.9m shares will be issued on or before 3 August 2015, subject to shareholder approval.RBC Capital Markets said: "Acquiring acreage at this stage - ahead of growth in interest in onshore plays - makes sense."