Media Releases › Central Petroleum View All Central Petroleum News HORIZONTAL WELLBORE TO TEST SURPRISE-1 12 Dec 2011 09:46 AM - Lateral completion of up to 700m planned to test Lower Stairway Sandstone - 17m of gross hydrocarbon column interpreted in Lower Stairway Sandstone - Permeabilities up to 420 Millidarcys (mD). For further information please download PDF below: Download this document