Roc has placed 9.9 million fully paid ordinary shares at a price of $2.00 per share to will raise $19.8 million from two established institutional investors.
The placement price represents a premium of about 11% to the weighted average price of Roc shares traded during the last 10 days.
The placement will substantially increase the number of Roc shares held by investors based in Europe, according to Roc chief executive John Doran.
"The primary purpose of the placement is to allow ROC to fund potential new exploration ventures offshore West Africa without recourse to either the proceeds generated by the sale of the Saltfleetby Gas Field or the funds raised by the April 2004 rights issue," Doran said.
"In the event that Roc does not identify appropriate new West African opportunities which meet its investment criteria, it is expected that the funds raised by the placement will be applied to the company's current African portfolio."
Cannacord Capital (Europe) Ltd, ROC's nominated adviser and broker on the UK Alternative Investment Market, will manage the deal.
The placement is expected to be completed on Thursday January 27.