Photographer, Fredric Alm. Used by explicit permission from LKAB. Remnants of the open pit mine with the mountain of Kiirunavaara cut in half on the right hand side. The city of Kiruna to the left on the brink of tumbling into the mine, and the lake in the top is situated on a second large orebody believed to be the actual old magma chamber, the ore body is named the Lake-ore and requires that the lake itself is moved to another location. Click on the image to view it in detail, it is well worth it.
The lava this time was from a sample taken from Kiirunavaara iron ore mine. It was a Kiruna type magnetite-apatite. Kiirunavaara is a very old volcano (1 900 million years old) of a very unusual type. It is situated within the Svekokarelian orogenic zone. The zone is filled with large ore bodies; the largest conglomerate of ore bodies is the Malmfälten (Ore-fields). It was constructed as very deep magma moved upwards from the core, forget mantle plumes, here we are talking about an actual core plume. That explains the ultra-pure ores in the area. It is normal with ores with an iron grade of up to 60 percent.
Kiirunavaara was in the 1870s a mountain 763 meters high, but in 1960 the mountain was gone and the mine went subsurface. Since then it has gone through 5 main levels, the fifth being at a record breaking 1 365 meters depth.
The magma intrusion formed a hangwall 8o meters thick, 4 000 meters wide, and with a known minimum depth of 2 000 meters, but with no known restriction at depth. As it goes deeper the ore body widens. Since the intrusion is slanted at 55 degrees angle the amount removed reaches more than 2 500 meters making the mine that largest and deepest iron ore mine on the planet. Since the start more than 950 million tons of iron ore has been extracted.
Photograph from Wikimedia Commons. The abandoned open pit mine at Kiirunavaara. Click to view the details.
It is prognosticated that the Malmfälten contains a reserve of iron ore that would guarantee the current production (5 percent of world consumption) for 250 000 years. That number is actually more mind-boggling than the scale of the operations in Kiruna.
Lonely Planet has put the mine in the highest category as a must to visit. The mine is open for visitors year round, one of the few open for visitors. It is a true Mecca for all rock nuts, volcanoholics and general mine fetishists.
The 540 meter level was used in the late eighties for growing ordinary mushrooms, but as prices plummeted the company that borrowed that part of the mine switched to growing Shii-take instead. The mine proved to be perfect for that particular mushroom. Since Shii-take is highly sporous it has pervaded into all parts of the mine through air ducts. So, at any part of the mine where there is light you can find Shii-take growing from the bare rocks, sometimes one can even find them on the machines. Today the mine is one of the top producers of this tasty mushroom.
Shii-take growing on a slab of iron ore.
There are two other large mines in Kiruna, both of them closed in the eighties during the world wide steel crisis. The Luossavaara Mine was of the same type as Kiirunavaara Mine, the ore body is probably connected at depth with the Kiirunavaara ore body. The other, Tuollavaara Mine, is a comparatively slender low-phosphor hematite ore. And with slender we are talking about 6 ore bodies that are on average 30 meters thick and 150 meters wide with unknown depth.
The entire city is now going to be closed down and moved since it is soon going to fall down into the hole created as the slanted hangwall caves in on itself and falls down into the mine. The same fate also awaits the City of Malmberget (Ore Mountain).
Economically it is one of the world’s leading power hubs. The area sprouts 4 operational mines on mammoth scale, among them the largest copper mine on the planet. And several more are being projected or are in startup phase to ensure a production yield of up to 20 percent of the world’s annual iron consumption. During the next 20 years a staggering 130 billion Euros are going to be invested in building new infrastructure, replacing two entire cities falling down into old parts of mines, and generally starting new mines and 2 new smelting plants. Income in the area is the highest in Europe and the city of Kiruna sports a 10 percent negative unemployment. The area has a gross municipal income surpassing many smaller European economies on a population of 35 000 deep frozen souls. The city of Kiruna also has its own spaceport and its own space program together with Virgin Galactic. In theory it would be a nice place to live in from a purely economic standpoint. Only problem is that the city resembles Mordor with a tinge of hell frozen over and then plunged into eternal darkness.
All of this due to the core having a burp 1.9 billion years ago, I am still curious about how that burp happened. It is a mystery that really should be solved; because I do not think we would like to be around if it happened again. The core contains a lot of not so nice stuff compared to the fairly friendly constituents of the mantle.
Russian Apatite, Wikipedia Commons. Click on the image for details.
The riddle was quite simply a rhymed word pun on apatite derived from apathy. Part of the poem was about it doing naught and being lethargic, the other part was about sitting in a chair as apatite sits in a matrix. Lair is of course the mine of Kiruna making the Riddle recursive of the Name the Lava competition with the Apatite-magnetite Iron ore. As someone said, it is easy afterwards. Here is the poem in orignal, and do not blame Alan for lack of poetic excuberance, I am guilty of it since Alan is on a mysterious walkabout.
I do naught,
I make naught.
Joyless in my chair,
deep in my lair,
I think naught.
CARL
