Andalusia is relatively active in terms of seismic activity. I’ve seen a couple of reports in the Facebook group for Olvera where people are talking about feeling something and one where people were reporting the windows properly rattling. I like technology and I thought it would be a bit of fun to put a seismograph in the house to track any local activity. It’s a bit trickier than I thought! It picks up everything and then it’s down to you to look at the traces to work out what is an earthquake and what is the bread van driving past or someone drilling 2 doors down. The sensor in mine will pick up a quake on the other side of the world so learning how to interpret what I see has become a bit of a challenge.
In the section above, you can see a few “things” happening. In all likelihood, these are anything but earthquakes.
This one, however, could well be.
Earthquakes have a couple of stages. P waves and S waves. So in the image above you can see it’s all quite quiet until about 08:52:40. Then you get about 10 seconds of slightly higher spikes (P waves?) followed by 15 or 20 seconds of much bigger spikes {S waves?). This coincides with a 2.8 magnitude quake about 100km from Olvera. I’m not going to even pretend that I fully understand what I’m looking at. From what I’ve seen so far, it does look possible. I’d love to hear from anyone who actually understands this stuff.
What I’m waiting for is something decent right in Olvera so I can look at the trace and tie it directly to something that people have felt.