The offer of 20 million shares priced at A$0.20 each will now end at 5pm Western Standard Time on 31 January 2013.
Sirocco had previously extended the offer to 21 December.
It also includes provision for oversubscriptions for a further 15 million shares to raise another $3 million.
Proceeds will be used mature drilling prospects within Block 14 onshore Sudan.
Studies have defined 1.5 billion barrels of gross unrisked prospective resource in Block 14, which covers 100,000 square kilometres.
This is contained in 30 potential traps that have gross resources ranging from 20 million barrels (low or P90) to 200 million barrels (high or P10) each, with the best estimate being 50 million barrels.
Sirocco is acquiring a 49.9% shareholding in Statesman Africa Limited, which holds a 75% working interest in the Block.
Already one well has been drilled immediately to the south of Block 14 in 2012 and has encountered oil shows. A further well is currently being drilled to the north of Block 14. Further success from surrounding exploration will have a significant positive impact on Block 14.
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