More than 300 earthquakes have been recorded at Whakaari (White Island) since last month's swarm began, however, activity has decreased in intensity and numbers.

GeoNet duty volcanologist Mike Rosenberg said 356 shakes were recorded since May 23 although the swarm had not resulted in any increase in volcanic activity or landsliding on the island.

Of the 356 quakes, 40 were of magnitude 3 or greater with the largest three being 3.9, 3.8, and 3.8.

Rosenberg said the swarm continued to appear tectonic in nature, unrelated to volcanic processes.


Although no landslides had resulted so far, a GeoNet landslide duty officer reported a heightened likelihood of landslides occurring as the earthquakes were shallow, local, and local material was relatively weak.

Landslides were also more likely during prolonged periods of heavy rain.

Rosenberg said observations were consistent with minor volcanic unrest and the Volcanic Alert Level remained at 1 while the Aviation Colour Code stayed at green.

While Volcano Alert Level 1 was mostly associated with environmental hazards, eruptions could still occur with little or no warning.

GNS Science continued to closely monitor the island and other active volcanoes.

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