For almost 4 years now I've been living in Papua New Guinea where I work as an Engineer for an aid organisation. I experienced many earthquakes in this country situated on the Pacific's Ring of Fire, for a long time. Last night I was printing something and the part was about to finish. The printer was completing the top layer when the quake struck. Around 5:35 PM we had a big 6.7 Richter scale degree earthquake that continued for more than 15 seconds at a very high intensity.
This is how the recording is looking like:
I printed this part in PLA and this modified Mendel/ Prusa i2 is the printer I was using for the job:
That's an interesting artifact. Almost looks like it was a transverse wave that was more or less perpendicular to the long axis of that part. Fascinating find!