The Mythic Kaalijarv
(Kaali Iron)
The beginning of worship – a cosmic connection of land and sky and power ....
From the far north and from a far ago time, the Kaali Iron pulverized the Earth of Estonia and its Island of Saaremaa.
History has shown that early man – in the face of extreme natural power – would frequently petition these forces for safety and relief. Such seems the case with Kaali.
Figure 1. Showing the direction of the meteorite.
The explosion of Kaali is estimated to have had a power greater than the Hiroshima bomb, burning the forests within a radius of 3.7 miles (6 km).
When Kaali hit, it produced nine craters. The largest is 333 feet (110 m) in diameter, with a rim 20–23 feet (6–7 m) above the surrounding land. Thought to be an explosion crater because of the high rim and uplifted surrounding rock, it holds a pond about 53 feet (16 m) deep.
Here's a drawing of the main crater and four of its close impact craters.
Figure 2.
1 - Kaali main crater (100 m); 2 - Ilumetsa Põrguhaud (76 m); 3 - Ilumetsa Sügavhaud (47 m);
4 - Tsõõ¬rikmägi (40 m); 5 - Simuna (9 m, after Pirrus 1995).
Some of the craters are dry and range from 40 to 143 feet (12 to 44 m) in diameter. In these small craters the dolomite bedrock was crushed into fragments by the force of the impact.
Here's another map showing placement and arrangement of the craters.
Figure 3.
Notice the impact breccia and crushed rock powder in this geological cross-section view:
Figure 4.
The main crater (A) and detailed geological cross section of its south wall (B) after Aaloe ( 1963): 1 - soil; 2 - uplifted dolomite; 3 - shattered dolomite; 4 - dolomitic powder; 5 - filling-breccia; 6 - dolomite; 7 - gyttia and peat.
You can better understand some of the force of the explosive main crater event with this photo of the uplifted dolomite:
Figure 5. Dolomite rocks at the Kaali main crater. They were horizontal before impact.
Many small iron meteorite fragments and meteoritic dust have been found and studied in the area. Mollusk fossils in the fillings of the small craters indicate the craters are 3,500 – 3,900 years old.
Here's a current high water photo of the main crater:
Figure 6.
Analysis from the Craters
To form these craters, the Kaalijarv meterorite was considered to have an impact velocity of 6.2 - 12.4 miles a second (10 - 20 km/s) and a mass of 20 - 80 tons.
At the altitude of 3.2 - 6.2 miles (5 -10 km) the meteorite broke into pieces, impacting the Earth in many different ways.
The largest fragment produced the main crater and the smaller fragments produced the other eight craters, scattered over an area roughly a 3/4 sq mile.
Human History
As a result of what must have been frightening power, the main crater became sacred for those living near the Baltic Sea, and the early Estonians built a high stone wall around it. Through the thousands of years, many Estonian myths and legends about the place and its horrific impact grew, some seemly to have traveled as far away as Greece.
In current history, in remembrance, Asteroid 4227 is named after Kaali.
Because of this history, how humans in the area reacted to Kaali's explosive power, the individual meteorite we have acquired is one of the special meteorites in our collection. It has a great fusion crust, with terrestrial alteration – defoliation.
It's also a gorgeous little iron, 42 grams:
Figure 7.
How did we acquire it?
Well, many universities and museums trade items from their collections for study and to extend their educational reach.
This sample of Kaali came from the National Museum of the Czech Republic via trade in 1994, and we were able to acquire it from NEMS (www.meteorlab.com) to use as a teaching example. As a result, we count ourselves as lucky lads.
Just The Specs
Iron, IA
Octahedrite, coarse (2.0mm)
shock-hatched and recrystallized kamacite structure
96.4% kamacite; 1.8% Ni-rich taenite; 1.7% schreibersite-rhabdite; and minor amounts of troilite and olivine
The precise age the impact event remains controversial:
-
About 4000 BP (Before the present), based on recent radiocarbon - and pollen-dating of sediments infilling the main crater (Saarse et al., 1991);
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Either 370 to 400 BCE (Before the Common Era) (Rassmussen et al., 2000), or up to
-
7600 BP (Raukas, 1997, 2000), according to indirect dating from surrounding mire deposits.
Fall: Saarema island, Estonia
Discovered and identified as meteoritic in 1937
Terms
As with other meteorites, the unique composition of Kaalijarv is educational, as well as its history.
Definition of Breccia
- n. A course-grained rock, composed of angular, broken rock fragments held together by a mineral cement or a fine-grained matrix.
- n. Impact Breccia – Broken rock fragments held together by a mineral cement or a fine-grained matrix created by meteoritic impact.
Here's an example:
This is a beautiful example of the impact breccia in Haughton Crater. It is a conglomerate of all kinds of rocks broken up and welded haphazardly together under the immense heat and churning of the impact.
http://www.marsonearth.org/multimedia/07.25.04.hmp.photo.report.html
Definition of Octahedrite
-
n. Most common type of iron meteorite, composed mainly of taenite and kamacite and named for the octahedral (eight-sided) shape of the kamacite ...
Polished slice of an Octahedrite iron meteorite, that has been etched with acids to show the Widmanstatten structure (crystalline intergrowth of the two Fe-Ni alloys, kamacite and taenite). © Smithsonian Institution.
http://www.museumwales.ac.uk/en/837/
Definition of Exfoliation
- n. The scaling off of a bone, a rock, or a mineral, etc.; the state of being exfoliated.
- n. A physical weathering process in which sheets of rock are fractured and detached from an outcrop. For clays, refers to the dissociation of clay basal sheets.
Geological exfoliation of granite dome rock in the Enchanted Rock State Natural Area, Texas, USA.
Wikimedia Commons.
Links
Here's a link to the American Museum of Natural History, discussing meteorite impacts:
http://www.amnh.org/exhibitions/permanent/meteorites/impacts/
Here's the International Meteorite Collectors Association (IMCA):
http://imca.repetti.net/metinfo/metclass.htm
Here's two dictionaries for reference:
http://www.science-dictionary.org/
Lexic also includes excellent pictures:
http://www.lexic.us/
Here's a link to the New England Meteoritical Services. Contact Dir. Kempton, and explain what you are looking for:
http://www.meteorlab.com
Earth Impact Database
http://www.unb.ca/passc/ImpactDatabase/images/kaalijarvi.htm
Figures & Acknowledgments
Figures
Figure 1. http://en.wikipedia.org/wiki/Baltic_Sea
Figure 2. From http://sarv.gi.ee/geology/figures.html
Figure 3. From the Geochemical Journal, Vol. 38, pp. 107 to 120, 2004.
Figure 4. From http://sarv.gi.ee/geology/figures.html
Figure 5. The photo was taken on 10 August 2005. Wikimedia Commons.
Figure 6. http://www.7is7.com/otto/estonia/kaali.html
Figure 7. Photo by New England Meteoritical Services. ww.meteorlab.com
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