Indonesia had multiple major earthquakes this year
- A series of earthquakes in Lombok between July and August, including a 7.0 mainshock
- The 7.5 earthquake + tsunami in Sulawesi, September 2018
- A 6.0 earthquake near Java, on 11 October 2018
I'm aware that Indonesia sits in an earthquake zone, but historically I don't think so many big ones occur in such a close time. Also, this spread out in different islands (e.g. the epicentres in Java and Sulawesi are ~1,000 km apart) over several months, so it doesn't look (at least to me) like typical mainshock-aftershock relationship. Were they related in some way? e.g. Do they indicate an increase seismic activity in the region?