By that definition, we have four options:
1: volcano
2: geyser
3: explosion
4: impact
I would vote for #3 explosion.
Since it apparently has a given name Shindrok's Crater. That could suggest that "Shindrok" (individual or forgotten group) was in some manner responsible for the crater. It may be that "Shindrok" only was responsible for its discovery and claimed it as such, Or that "Shindrok may have assumed ownership of that particular part of ground. Another view may have put Shindrok as a center point of a major historical event there.
Either way the name would have stuck and been passed down. Mainly due to the fact that it is a dominating terrain feature of the region. The name would have been passed along through word of mouth as a reference for travelers. The actual history may only be known by learned scholars, leaving only the folklore of the local inhabitants to explain the mystery of the crater and it's origin. The variations would the range in pieces of mixed fiction and fact, depending on the teller of the tale at the time
So, i feel that we would know something of it, in name at least. The history would not necessarily be a shared interest of the peoples of Yliakum other then to scholars as a subject of study. The common people would be happy with their versions of folklore. I kinda like the current mystery of the name.
