Conventional reservoir targets in TAG's Boar Hill acreage include Miocene-aged turbidite sandstones with porosities up to 20% or more. At least 20 conventional prospects and leads have been identified across the acreage with a number of prospects now drill-ready. Some of the more prominent, high-impact targets include the Boar Hill, Pauariki, KawaKawa, and the Arakihi Anticline prospects.
TAG Oil's initial focus is the Boar Hill structure, originally defined by the New Zealand Geological Survey in 1938. These early geological mapping expeditions noted the existence of oil and gas seeps in the area. TAG Oil completed a series of modern 2-D seismic lines over the Boar Hill structure, confirming sub-surface correlation to the earlier NZGS surface mapping.
In October of 2009, TAG Oil completed a 487m (1,600 ft) stratigraphic well, drilling through the Miocene section and set casing in the Oligocene aged Weber Formation in preparation for drilling the deeper section of the well. The shallow section of the well provided encouraging preliminary data as drill cuttings "head gas" analysis indicated progressively more oil-rich readings as the well penetrated the Oligocene strata.
Planning is now underway for the main Boar Hill-1 well to fully penetrate the underlying Waipawa and Whangai tight oil source rocks at an anticipated depth of 1600m (5,250ft).