Saturday, June 13, 2020

The book of boulders (Suomen Lohkareet)

My earlier post was about data sources for finding new caves. I've now been reading the Suomen Lohkareet (the book of boulders in Finland) book, and it is great.

The book recognises that it cannot cover all the million large boulders in Finland, but picks the most interesting ones. The boulders are described per category of interest, e.g., boulders with caves under them, boulder fields, those with historical events tied to them, fishing- or water-related boulders, and so on.

I did find many interesting places to visit from the book, and also some new data sources, such as GTK's Hakku website. GTK is Geologian Tutkimus Keskus or the national. geology research center. The book's URL seems outdated though, but the service can be reached at For instance, you can:
  • Find registered boulders, from GTK's or mining companies past research. Click on "Lohkarehavainnot" at the location data page.
  • Find all mines in Finland by clicking on "Kaivokset", again at the location data page.
  • Recent landslides and other movements, click on "Nuoret siirrokset ja maanvyöryt".
  • Ground rock type areas in the Helsinki region, click on "Kallioperän lohkot".
  • The data can either be browsed on the website or downloaded for free.
See more caving stories at, and all Planetskier and Planetcaver stories at Blogspot and TGR! This article, pictures and videos is (c) 2020 by Jari Arkko. All rights reserved.

No comments:

Post a Comment