Dan Sandiford edited Results.md  about 9 years ago

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##2014-10-10UTC10:20, near Korumburra, Estimated magnitude: 1.5  A small event near Korumburra (?? add hypocentre, (M 1.5,  2014-10-10UTC10:20) provided an opportunity to compare waveforms on surface and subsurface instruments. Whilst While  P-wave arrivals can be easily detected on borehole stations, they are difficult to detect on surface stations.S-waves arrivals from borehole stations will substantially improve event location.  Figure 2 shows this event at the nearest borehole station, and Figure 3 shows the corresponding STA/LTA filter response, which is commonly used for automatic event detection. Figure 3 shows the P and S-wave picks from the borehole station furthest from the event.   Figure 4 shows the event at the nearest telemetered surface staion. Whilst the event is clearly present on the surface record, the signal to noise level is much smaller. Also, no clear S-wave arrival can be determined. The corresponding STA/LTA filter shows multiple spikes of similar amplitude, meaning that any automatic detection routine using a STA/LTA filter is ambiguous.   ##2014-10-17UTC08:13, near Moe, Estimated magnitude: 3.2  A magnitude 3.2 earthquake felt locally in the Moe earthquake occurred within 10 Kms of a borehole instrument on 17 October, 2014. This allowed us to trial a Non-linear earthquake location method, which we are currently developing as the network -standard. The results of the location are shown in Figure 8.  #Future work