Former riverbeds under the seas of the South Taranaki coast may be rich in iron and Trans-Tasman Resources has extended its prospecting area to include them.
The Patea and Whangaehu Rivers were likely to be particularly rich in ironsand, Trans-Tasman executive environment and approvals manager Andy Sommerville said. It was eroded
from Mounts Taranaki and Ruapehu and was probably still there on the seabed.
The company has just got a new prospecting licence that extends beyond the 12-mile territorial waters limit, to take in the former riverbeds. The area is just outside the company's existing prospecting area off the coast of Wanganui and South Taranaki.
The new licence covers 3314sq km and is for an initial term of four years.
Trans-Tasman is prospecting for iron ore, called titanomagnetite.
The first stage of prospecting the new area would be an aerial survey, with magnetic instruments picking up the presence of iron. After that sand would be drilled up from the seabed and tested for iron content.
Meanwhile, the company's shallow drilling programme, closer to the Waverley/Patea coast, will continue shortly.
It will use the New Zealand Dive and Salvage boat Island Leader II, which will occasionally be at Wanganui's port for supplies.
Mr Sommerville said the company was in the early stages of determining the size of the ironsand resource.
When that was clear, it would go into an exploration phase to determine the ironsand area's size, mineability and usability.
Mining could be done from a fixed offshore rig, with sand sucked up from the sea floor, processed to concentrate the iron and then shipped to Asia in bulk carriers.