Waipawa Shale

The Waipawa Black Shale.

The Fractured Waipawa Black Shale
Black shales are fine grained, sedimentary rocks; usually composed mainly of clay materials, that have a high amount of carbonaceous and organic material within the matrix of the rock. Black shales are the rich hydrocarbon source rocks found in many parts of the world. Examples include the Bakken Shales in North Dakota and Montana, the Monterey Shales of California, and the Kimmeridge Claystone in the North Sea.

A World-Class Source-Rock
The Waipawa Black Shale is a fractured, poorly bedded, organic-rich siltstone of Paleocene age, deposited in an anoxic, limited circulation, marine environment. Outcrop sampling indicates average total organic carbon (TOC) values of 5% and average Hydrogen Index (HI) of 245, with maxima of 12% TOC and 550 HI, respectively. The formation occurs throughout Trans-Orient’s East Coast Basin acreage and has also been identified in other areas of New Zealand. The Waipawa Black Shale is normally 30m or more thick and achieves a maximum thickness of 70m in Southern Hawke’s Bay. The organic carbon is primarily of marine origin, although significant terrestrial organic matter is evident in some samples.