New Zealand’s East Coast Basin contains two extensive and extremely thick shales, the Whangai and Waipawa. Both are observable in surface outcrops and have proven to be the source of the region’s natural gas and oil seeps.
The shales were not targeted in previous oil and natural gas drilling, however, because shales were too impermeable or “tight” to be commercially productive using historical technology. The recent revolution in unconventional oil and natural gas exploitation has demonstrated the commercial viability of numerous gas and oil-bearing shales, mainly in North America. This has triggered worldwide interest in testing and commercializing hydrocarbon-bearing shales.
NZEC and other operators in New Zealand see strong potential to develop the Whangai and Waipawa shales using modern technology. The Company has drilled two stratigraphic wells on its Castlepoint Permit to collect information about the Waipawa shales, and one well (Ranui-2) on its Ranui Permit to collect additional information about the Whangai shales.
A number of key parameters in both shale formations have been observed as set out in the table below. It must be noted that these estimates are based on limited data and are subject to revision and refinement as further technical work and exploratory drilling are conducted. The preliminary figures indicate that the Waipawa and Whangai shales share many positive characteristics with the highly productive Bakken shales in Saskatchewan and North Dakota.
Download the PDF table on Oil Shale Comparison.