English: Waiowa (also known as Goropu) is an isolated pyroclastic cone that was formed during 1943-44 by explosive eruptions through Paleozoic to pre-Cambrian metamorphic rocks. The active vents, seen here on February 14, 1944, were formed in an area without previous volcanic activity. Intermittent minor explosions began on September 18, 1943. Larger explosions occurred on December 27, 1943, and on February 13 and July 23, 1944. After the final eruption on August 31, the volcano was capped by a 500-m-wide crater that now contains a small lake.