The Tarkine region is Home to a wide variety of Tasmania’s diverse mineral assemblage and hosts the oldest landforms on mainland Tasmania. The only place you can experience 4 different ultrabasic in close proximity to each other, Granite. Basalt, Dolerite and Gabbro.
“The Arthur Lineament, a geological feature in the Tarkine, is Tasmania’s most extensive basalt plateau that retains its original temperate rainforest ecosystem.”
Web Source : http://www.tarkine.org/rainforest/
The Arthur Lineament is actually Dolerite, (US) Diabase or microgabbro . It is Not actually Basalt, to correct the often misinformed tarkine.org. This from someone (Scott Jordan) that grew up in a mining town and worked in field exploration (apparently)