Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

Sm

Samarium concentration in ppm.

Eu

Europium concentration in ppm.

Gd

Gadolinium concentration in ppm.

Reference

Reference material.

Compute the chondrite- or PAAS-normalized europium anomaly Eu/Eu* from Sm, Eu and Gd concentrations. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Eu anomaly

Europium anomaly Eu_N / sqrt(Sm_N * Gd_N).

• Classification diagrams and geochemical ratios require appropriate normalization, oxidation-state treatment, volatile basis, analytical quality, alteration screening, mineral or whole-rock context, and a composition within the method's calibration domain.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

• REE Anomaly Ce Calculator

  Compute the chondrite- or PAAS-normalized cerium anomaly Ce/Ce* from La, Ce and Pr concentrations.

• REE Normalization Calculator

  Normalize rare earth element concentrations to chondrite or PAAS and report Ce and Eu anomalies.

• Crystal Fractionation Calculator

  Rayleigh fractional crystallization C_l = C_0 * F^(D-1) with F the fraction of liquid remaining and D the bulk partition coefficient; concentrations in ppm.