The Whangarei volcanic field, named after the adjacent Whangarei Harbor, consists of Quaternary basaltic scoria cones and lava flows. The field lies in the central part of the Northland Peninsula, at the southernmost end of the Northland Intraplate Province. In addition to the younger dominantly basaltic rocks, Miocene dacitic lava domes and rhyolitic breccias are also present at Whangarei. Quaternary volcanics form a group of large cones SE of Whangarei, a NE-aligned group of scoria cones north of the city, and a group of lava flows east of the city along a major fault. The youngest basalts were mapped as Holocene (Kear and Thompson, 1964), although the age of the field is not well known and there are some indications that the latest eruption may have been during the late Pleistocene, about 30,000 years ago (Latter 1994, pers. comm.).