Incompatible element

As Incompatible element or Incompatible trace element those chemical elements are identified in the petrology and geochemistry that do not fit due to their ionic charge or radii in the crystal structure of normal rock- forming minerals, which is why they are mainly found in pegmatites.

During the fractional crystallization of magma and the formation of magma by partial melting in the mantle go incompatible elements preferentially into the melt or remain in it. This happens especially in the cases where the distribution coefficient between rock-forming minerals and melt is significantly smaller than 1.

In geology, working with so-called normalized spider diagrams to give, for example, information on the crystallization behavior of a magma can, thereby, the elements are always left on inkompatibelsten.

Two groups of incompatible elements are referred to with acronyms derived from the English.

LILE

The first group has large ionic radii, it is ' called, LILE (large -ion Lithophile elements ). These include

  • Potassium
  • Rubidium
  • Cesium
  • Strontium
  • Barium

These elements are considered to be relatively mobile and volatile.

HFSE

The second group contains elements with high Ionenvalenzen, it is called, HFSE '(high field strength elements ). These include

  • Rare earth metals
  • Thorium
  • Uranium
  • Zirconium
  • Hafnium
  • Niobium
  • Tantalum

These elements are considered to be relatively immobile.

Fractional crystallization (geology) Mantle (geology) Ionic radius Rare earth element
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