The earthquake activity in the South Pacific between Vanuatu and Tonga has continued over the past week, according to data made available by the US Geological Survey.
Archive for March, 2006
Just before midnight on Monday the 5th of March 1934, people throughout the lower North Island were startled from their sleep and ran for doors as a severe earthquake struck. Chimney bricks rained into houses, windows shattered and furniture tipped over; the ground rumbled and there was a great noise of goods being thrown about while slips ran down hillsides, bells rang and window weights clanged.
A woman collapsed and died of fright as did a man as he fled his damaged home. In Wellington, the carillon bells rang as the clappers struck the fixed bells while the tower swayed.
Fed up with endless raking over the scraps of scandal thrown us by the politicians in the hope that we will overlook the fact that they’re not doing much?
If so, then tune into local radio to find out about the good things that are happening in the world. Astronauts holding radio interviews with school students. What’s happening on the sun. A potted history of the LP, CD and audio cassette. New techniques in earthquake forecasting. Much more
WorldFM broadcasts a number of music and documentary programmes and their schedule is available at the weblink on this site.
On “This Week in Amateur Radio” there was much of interest to the ordinarily inquisitive person as well as snippets to keep a DXer or radio ham tuned.
Gas from magma (molten rock) triggered the volcanic eruption at Raoul Island on March 17th, reports Geonet.
This means that the likelihood of magma-related activity at the volcano is now higher than originally thought.
Following last Friday’s eruption at Raoul volcano, GNS Science has issued a bulletin based on an aerial inspection from an RNZAF Orion on March 21st.
It states that Green Lake has risen by 6 to 8 metres and drowned most of the formerly active vents, while some of the craters dating from the 1964 eruption have reactivated. A fumarole at Bubbling Bay is now a crater 20 to 30 meters across and there are new craters inside the volcano.
Since the eruption at Raoul Island last Friday, the area between Vanuatu and Tonga has experienced 11 earthquakes of magnitudes between 4.2 and 5.9 at varying depths and locations according to data provided by the US Geological Survey.
The earthquakes are occurring in an area known as the Fiji Microplates where a southward projection of the Pacific Plate and a northward projection of the Australian Plate are moving apart.
The crater lake at Raoul Island may have risen between 6 and 8 metres according to vulcanologists.
An RNZAF aircraft flew a vulcanologist over the island yesterday to determine whether it was safe for a research and recovery team from New Zealand to land on the island. The team which includes GNS scientists, a Police recovery team and the 5 DOC scientists who were evacuated after last Friday’s eruption were given permission to leave their vessel and land on the island.
The scientists will be involved in studying the effects of the eruption as well as maintaining seismometers and other equipment on Raoul. If it is determined that the volcano is becoming less active, they will commence repairing some of the damage to the island’s facilities.
The police recovery team were intending to search for the missing DOC scientist who was near the crater lake at the time of the eruption. However, as the lake level has risen and may still be rising, their search will be delayed.
“Raoul’s calling you and he sounds worried!” said the radio technician at Makara Radio when I answered the orderwire.
On learning of the recent eruption at Raoul Island and the successful evacuation of 5 of the 6 Department of Conservation staff, I was reminded of a similar incident in the 1980s.
Thirty years ago, the residents of Hawkes Bay, Wairoa and Gisborne were greatly alarmed by the swarm of shallow earthquakes that plagued the area in late March of 1976.
The swarm, centred about 30 km south of Wairoa, included four 5th magnitude earthquakes which caused considerable damage in the township.
Yesterday’s eruption at Raoul Island in the Kermadec Island chain is a sharp reminder that New Zealand sits astride a very active part of the Earth’s surface.
The eruption was small by New Zealand standards, but no doubt was harrowing for the Department of Conservation (DOC) scientists who experienced it. Five of the scientists were evacuated to Auckland by helicopter last night but one, who was carrying out a routine testing of water temperatures inside the volcano when Green Lake erupted, is still missing.
Alternating still and windy conditions with low rainfall have characterised the first half of March here in Tawa.
The powerful Arthur’s Pass earthquake of 1929 was the first of a series of nine strong earthquakes that were to cause serious damage and loss of life in New Zealand as it reeled from the effects of The Depression.
Geonet, the USGS (NEIC) and IGNS reported 32 earthquakes in the New Zealand area between the Kermadec Islands in the north, and the Auckland Islands to the south during February 2006. The magnitude distributions were as follows:
M6 to 6.9 (1), M5 to 5.9 (2), M4 to 4.9 (18) M3 to 3.9 (11).
An additional 4 events in the magnitude 2 range were deemed worthy of mention.
The swarm of earthquakes occurring 30 km south-west of Wanganui has continued. The swarm commenced with a magnitude 4.1 earthquake just before 1 a.m. on Saturday 11th. A further four events of magnitude 4.3, 4.5, 3.8 and 4.2 occurred up until 8:10 a.m.
A magnitude 3.4 quake then struck just after 3 o’clock on Saturday afternoon.
Another magnitude 4.2 tremor was felt in Wanganui just after two this morning according to Geonet, bringing the total number of earthquakes in the swarm to seven. All of the earthquakes have occurred at a depth of 30 km.
The latest swarm is taking place just after a series of light but deep earthquakes under the central North Island. A similar pattern of deep earthquakes occurred prior to two of the Wanganui swarms during May/July and July/August last year.
The members of the latest earthquake swarm are more numerous and slightly stronger than those of the three Wanganui swarms that occurred in 2005.