The seismograph is located in Hawker Motors, the seismometer is located about 15 kms north east of Hawker.
The paper on the drum covers a 24 hour period of recording. The graph drum turns very slowly and each minute the pen gives a small deflection this is what we call a minute mark. The drum moves at 1 mm per second and takes 15 minutes for one revolution and there fore 4 revolutions for the hour. A minute mark deflects for 2mm, an hour mark is 4mm, a six hour mark is 6mm and at 24 hour there is no mark, it is only a straight line.
The Flinders Ranges is continually rising and for that reason there are many small quakes as the tension changes on the fault lines. Fault lines can be seen on Page 4 of the sheet that can be downloaded at this link.
If you are interested in earthquakes you can see what is happening at Geoscience Australia, or the Seismological Association of Australia Inc (SAA)
There are a number of web sites to visit:
This sheet is from the Hawker Station.
On the drum at the Hawker Station.
This is a good record of an event.
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