Lecture 6-10: trace element geochemistry

1. Review of equilibrium constant
   1. Gibb's free energy of reaction
2. Trace element definitions
   1. Compatibility and partition coefficients
   2. General trends in compatibility
   3. The relationship between partition coefficients and equilibrium constants
3. Thermodynamic basis for compatibility
4. Crystallization/melting models and trace elements
   1. Batch crystallization: trace elements
   2. Fractional crystallization
   3. Bulk partitioning
   4. Muskox Intrusion
   5. Fractional melting

We acknowledge and respect the lək̓ʷəŋən peoples on whose traditional territory the university stands and the Songhees, Esquimalt and W̱SÁNEĆ peoples whose historical relationships with the land continue to this day.

Trace elements, compatibility, and general trends.

Equilibrium constants and partition coefficients. Ni exchange in olivine.

Thermodynamic model for compatibility. Energy to displace lattice:

Integral.

Thermodynamic model for compatibility. Ion exchange with Ca.

Thermodynamic model for compatibility. Returning to $\Delta$G and partition coefficients.

(equilibrium review hand notes, digitize for 2025)

Periodic table, general patterns in ion size

Batch melting or crystallization: conceptual
drawing...

Batch melting or crystallization: derivation

Batch melting or crystallization: predictions

Fractional crystallization: conceptual

Fractional crystallization: derivation

Fractional crystallization: examples

Bulk Partitioning

Bulk Partitioning

Bulk Partitioning

Muskox Layered Intrusion Example

Solution.

Fractional melting: concept and derivation

Fractional melting: concept and derivation