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.

D30

Sieve size at 30 percent finer in millimeters.

D60

Sieve size at 60 percent finer in millimeters.

D10

Sieve size at 10 percent finer in millimeters.

Compute the gradation curvature coefficient Cc = D30^2 / (D60 * D10) from grain sizes in millimeters read from a gradation curve. 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]

Cc

Curvature coefficient Cc (dimensionless).

• Geological models are scale-, site-, method-, and calibration-dependent. Heterogeneity, anisotropy, sampling, diagenesis, pressure-temperature history, instrument response, boundary conditions, and empirical-correlation range can dominate the result.
• 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.

• Uniformity Coefficient Calculator

  Compute the uniformity coefficient Cu = D60 / D10 from grain sizes in millimeters read from a gradation curve.

• Hazen Grain Size D10 Calculator

  Invert the Hazen formula K = C * D10^2 to estimate the effective grain size D10 in centimeters from hydraulic conductivity in cm/s and the Hazen coefficient in 1/(cm*s).

• Coefficient Of Volume Compressibility Calculator

  Coefficient of volume compressibility mv = av / (1 + e0), where av = de / d_sigma' is the slope of the e - sigma' curve over a loading increment. Result in 1/kPa.