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.

Vrms1

RMS velocity to the shallow reflector in meters per second.

Vrms2

RMS velocity to the deep reflector in meters per second.

t1

Zero-offset two-way time to the shallow reflector in seconds.

t2

Zero-offset two-way time to the deep reflector in seconds.

Dix (1955) interval velocity Vint^2 = (Vrms2^2 t2 - Vrms1^2 t1) / (t2 - t1) from RMS velocities in meters per second and zero-offset two-way times in seconds. 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]

V int

Interval velocity of the layer between the two reflectors in meters per second.

• Seismic magnitudes, moments, travel times, velocities, resolution, and energy depend on instrument correction, Earth model, phase picking, geometry, attenuation, radiation pattern, bandwidth, and calibration range. Magnitude scales are not universally interchangeable.
• 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.

• Seismic Rms Velocity Calculator

  Layer-root-mean-square velocity Vrms^2 = sum(Vi^2 ti) / sum(ti) from per-layer velocities in meters per second and one-way interval travel times in seconds.

• Seismic Resolution Horizontal Fresnel Zone Calculator

  First Fresnel zone radius r = (V/2) sqrt(t0 / f) governing horizontal seismic resolution, with velocity in meters per second, zero-offset two-way time t0 in seconds and dominant frequency f in hertz.

• Seismic Two Way Time Calculator

  Convert depth to seismic travel time: t = z / V for the one-way time and twice that for the zero-offset two-way time, with depth in meters and interval velocity in meters per second.