I’m all a-tremble

My living room, 8.53 pm. I’m sitting back on my couch with my feet up, watching Who Do You Think You Are, when I feel movement. “Hmmm… earthquake…” I stayed put, figuring it would be over in a few seconds. Earth tremors in Australia are fairly rare, and those that cause damage are even rarer.

This one seemed to go on and on, though. “Okay, that’s enough. You can stop now,” I said, as I took a firmer hold on the couch. It was getting a bit scary. Even after the initial tremor things kept moving for a couple of minutes.

The earthquake (green marker on the map) originated near Trafalgar and Moe, in Gippsland, eastern Victoria, not far from Darnum, where I grew up (about 18km west along the Princes Highway).


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I now live about 120km from the epicentre, and given the way my home shook I’m glad I wasn’t back on the farm. My sister still lives in that area and she thought she was going to be tipped out of her armchair.

The tremor has been rated at 5.2 by the US Geological Survey, and was minor compared to the quakes suffered by people in other parts of the world (although it was apparently the biggest to hit Victoria in more than a hundred years). Because earthquakes are so rare here it will be a major talking point for a day or two.

The New Zealand Herald reported on May 25, “Christchurch was hit by its largest earthquake in recent weeks this afternoon, with a 5.2-magnitude shake…” Between September 2010 and December 2011 Christchurch experienced four earthquakes of magnitude 6 or more. There were another 21 of magnitude 5.2 or more! See Christchurch Quake Map for details.

The twinge of fear I felt when tonight’s tremor continued for 30 or 40 seconds (much longer than the previous one a couple of years ago which was over almost before it began) makes me wonder even more how people who live in earthquake-prone regions cope. I can’t imagine what the people of Christchurch go through each time the ground begins to shake yet again.

Australia really is blessed when it comes to natural events that cause loss of life and property damage. We do have them – cyclones, fires and floods (and two earthquakes in my lifetime that caused fairly widespread damage) – but not on the scale and the frequency other areas of the world have.

Do the Easter Island statues have bodies?

An email doing the rounds at present expresses surprise that excavations have revealed that the stone statues on Easter Island in the Pacific Ocean are actually buried and that under the surface they have bodies.

This is not actually a surprise for archaeologists, who have been studying the statues on the island for about a century (that’s archaeologists in general – not particular people), and have been aware of the torsos since the earliest excavations in 1914.

The current digs referred to in the email are being conducted by the Easter Island Statue Project. In an article, Easter Island heads have great bodies! Jo Anne Van Tilburg, the director of the project, explains that about 150 of the statues on the island stand upright on the slopes of the quarry where they were carved. They are buried to varying degrees by material washed down from above. After the existence of the statues was reported to the outside world in 1868 “many sketches, essays, newspaper articles, and books were published describing the statues embedded in the slopes as ‘heads’.” More than 90 excavations since that time have uncovered bodies of statues.

The EISP website has excavation reports and lots of photos.

When is an error not an error?

In the western USA wilderness, just off Route 160, stands the Four Corners Monument. It marks the spot where four states – Utah, Colorado, New Mexico and Arizona – meet. Tourists have been visiting the spot for more than one hundred years so that they can straddle the boundaries.


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There have been claims that the monument is actually two and a half miles (4km) too far west. The north-south boundary between the states is at 109 degrees 03 minutes West, and people apparently assumed that the intention was that it should be at exactly 109° W. This seems to have arisen because Congress determined that the north-south line should be at the 32nd meridian of longitude west of the meridian that runs through Washington DC, which is at 77° 03′.

Four Corners Monument
The Four Corners Monument marks the spot where Utah, Colorado, New Mexico and Arizona meet

The US National Geodetic Survey (NGS) issued a statement in 2009 explaining why the Four Corners monument is in exactly the right place. The surveyor given the job of determining the boundaries in 1875 did get it slightly wrong – it’s actually about 1800 feet (548m) east of where it was intended to be – but, given the information and technology he had, the NGS is satisfied it’s in the right place.

What’s more, they say, “A basic tenet of boundary surveying is that once a monument has been established and accepted by the parties involved (in the case of the Four Corners monument, the parties were the four territories and the U.S. Congress), the location of the physical monument is the ultimate authority in delineating a boundary. Issues of legality trump scientific details, and the intended location of the point becomes secondary information. In surveying, monuments rule!”

More detail at Why the Four Corners Monument is in Exactly the Right Place