Lake Taupo Earthquake Swarm

Activity associated with an earthquake swarm located in the southern part of Lake Taupo has increased this morning with GeoNet reporting eight shallow earthquakes with magnitudes between 2 and 4.

Saturday 27th June 2009

An earthquake swarm close to Turangi on the southern shore of Lake Taupo has increased activity this morning. The swarm activity began on June 16th when the first of 17 events was reported by GeoNet. In all, four quakes were reported on Tuesday 16th, the events having magnitudes between 2.6 and 2.9.

Activity eased until a magnitude 2.4 earthquake was reported felt at dawn on Sunday 21st. A magnitude 3.5 event was reported just after midday on Thursday 25th, followed by three quakes with magnitudes between 2.9 and 3.1 on Friday.

Today’s activity commenced at 1 a.m. with a magnitude 4.3 earthquake located underneath Lake Taupo, 10 km north-west of Turangi, at a depth of 3 km. A magnitude 4.4 quake at the same location, but slightly deeper at 5 km, was reported at 5:21 a.m. A pair of magnitude 3 quakes struck shortly after, at 5:37 a.m. Four more earthquakes, with magnitudes between 2.7 and 3.4, had been reported up until 2 o’clock this afternoon.

Some residents of Turangi and the Lake Taupo settlements of Kuratau and Pukawa reported minor damage from this morning’s two larger events which they rated at MM6. GeoNet defines the effect of MM6 shaking as, “Felt by all. People and animals are alarmed, and many run outside. Walking steadily is difficult. Furniture and appliances may move on smooth surfaces, and objects fall from walls and shelves. Glassware and crockery break. Slight non-structural damage to buildings may occur.”

The latest swarm of 17 events have all occurred within 10 km of Turangi, at depths of 8 km or less. Ten of the events have been to the north of the town, beneath or on the shores of Lake Taupo. Only two of the events have been magnitude 4, with seven at magnitude 3 and eight at magnitude 2.

Four of the latest sequence have been located to the west of Turangi near to the location of a swarm of about 35 earthquakes which struck on the afternoon of Sunday May 31st and the following Monday morning. This swarm included seven quakes of magnitude 3, with most being 2nd magnitude.

[Compiled from data provided by the GeoNet project and its sponsors EQC, GNS Science and FRST.]

4 Responses to “Lake Taupo Earthquake Swarm”

  1. Darren says:

    Hey – any idea what’s going on there?
    These comments in the media have me wondering if there isn’t more than just a ‘land slide’…

    “Seismologists and civil defence staff would monitor the area after increased seismic and geothermal activity raised the risk of a major landslide above the village.”

    “Bird life had disappeared. A stream mouth at the village, near a waterfall, had shifted 40 to 50 metres.

    Mr Howard said there were some reports of streams drying up and of other spots where streams started to flow where there were none before.”

    http://www.stuff.co.nz/national/2550848/More-quakes-hit-evacuated-Waihi-Village

  2. DM says:

    Sounds volcanic in origin, if the reports are true, at the very least there has been a lot of ground movement!

  3. Ken says:

    The land area above Waihi village is quite spectacular – the bush-clad slope is clearly visible when driving around the western side of Lake Taupo from Turangi. Just past one of the access roads to Tokaanu power station the land on the left becomes very steep and Waihi village is on the right. The slope is clearly steaming even on warmish days.

    I’m not surprised that they are nervous about the possibility of a landslide when the conditions are right. A sudden collapse would be disastrous for Waihi and the seiche on the lake could damage moorings and jetties (or cause worse damage if large enough).

    From memory a similar set of conditions sparked an alert about 4 years ago. I’ll see if I can scare up more info and provide an update.

  4. John says:

    Recent swarms in this area from Lakes Rotopounamu & Lake Roto Aira asppear to be on the increase. The central point ap[ears to be slightly south and 5 kms west of Turangi but before the Tokaanu power station. Has anyone done a study of the fact that L Rotopounamu has faulting down in to L Roto Aira and L Roto Aira has faults through to L Taupo through the slipping volcanic field above Little Waihi and East towards Turangi. Although some 10kms away the Lakes of Roto Aira and closer/high L Rotopounamu appear to havr a significant bearing on the ‘slip area’. Swarms of June/July 2009 and now in 2010 though small appear to be becoming increasingly more numerous. Raukomoko reports such swarms often indicate volcano beginnings. Comments?

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