Kivettymiseen

Kivettymiseen refers to the process of fossilization in Finnish. It is the geological and biological phenomenon whereby the remains of an organism are preserved in rock. This process typically occurs after death, when the organism's soft tissues decompose, but its hard parts, such as bones, shells, or teeth, are gradually replaced by minerals. Over vast stretches of time, these mineral replacements create a stony replica of the original organism, becoming a fossil.

The conditions necessary for kivettymiseen are specific. Rapid burial of the organism is crucial to protect it from scavengers and decay. Sedimentary environments, like those found at the bottom of lakes, rivers, or oceans, are ideal for this. As sediment accumulates, it exerts pressure and, over geological epochs, can lead to the petrification of the buried remains. Groundwater rich in dissolved minerals, such as silica, calcite, or pyrite, plays a vital role in the replacement process. The minerals precipitate out of the water and infiltrate the porous structure of the organic material, effectively turning it into stone.

Different types of kivettymiseen exist, depending on the specific minerals involved and the extent of alteration. Permineralization, where minerals fill the empty spaces within the original structure, is a common form. Replacement, where the original organic material is dissolved and simultaneously replaced by minerals, is another. In rare cases, the original material can be completely replaced, leaving a detailed cast or mold of the organism. Fossils formed through kivettymiseen provide invaluable insights into past life forms and the ancient environments they inhabited.