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.

SiO2

SiO2 weight percent on the x axis.

Oxide name

Oxide being plotted, e.g. MgO.

Oxide wt%

Oxide weight percent on the y axis.

Prepare one silica-versus-oxide point pair for a Harker variation diagram. 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]

X (SiO2)

X coordinate in SiO2 wt%.

Y (oxide)

Y coordinate in oxide wt%.

Oxide

Trimmed oxide label.

• 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.

• TAS Diagram Plot Calculator

  Prepare total-alkalis versus silica coordinates and the Le Bas silica band for plotting on the IUGS TAS diagram.

• AFM Diagram Calculator

  Convert whole-rock oxides to AFM coordinates with ferric iron recalculated to FeO for the tholeiitic-calc-alkaline AFM triangle.

• Bubble Point Pressure Vasquez Beggs Calculator

  Invert the Vasquez-Beggs solution-GOR correlation to obtain the bubble point pressure; pass the separator-corrected gas gravity.