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Sonic Porosity Raymer-Hunt-Gardner Method Calculator

Φsonic=CRHGΔtΔtmaΔt\Phi_{sonic}=C_{RHG}\frac{\Delta t-\Delta t_{ma}}{\Delta t}

Enter the required inputs, confirm the units, and run the calculator to solve Phi_sonic. Review the formula source and assumptions before using the result in engineering work.

Tabular solver

Inputs

Defaults provide a quick field-unit example for the equation.

3 variables

Your input values and calculation stay in this browser.

Engineering reference summary

Calculation context and source notes

Sonic Porosity Raymer-Hunt-Gardner Method calculates sonic porosity for rock properties workflows in petrophysics. The page keeps the declared variables, units, source relationship, and output definition visible for technical review.

Use this formula when the listed inputs (Delta_t, Delta_t_ma, C_RHG) are known and the assumptions behind the cited rock properties relationship match the engineering case being checked.

Solves for

Phi_sonic (fraction)

Formula reference

Formula, variables, and default calculation

Φsonic=CRHGΔtΔtmaΔt\Phi_{sonic}=C_{RHG}\frac{\Delta t-\Delta t_{ma}}{\Delta t}

Reproducible default result

With the default values shown below, the calculation returns Phi_sonic = 0.209375 fraction. Defaults demonstrate the implementation; they are not recommended field values.

Delta_tus/ft

80

Delta_t_maus/ft

55

C_RHGdimensionless

0.67

Input definitions

Delta_t

us/ft

Sonic Log Transit Time Reading

Delta_t_ma

us/ft

Matrix Transit Time

C_RHG

dimensionless

Raymer-Hunt-Gardner Empirical Constant

Output definitions

Phi_sonic

fraction

Sonic Porosity

Delta_t

us/ft

Sonic Log Transit Time Reading

Delta_t_ma

us/ft

Matrix Transit Time

C_RHG

dimensionless

Raymer-Hunt-Gardner Empirical Constant

Engineering use, assumptions, and limits

Use this formula when the listed inputs (Delta_t, Delta_t_ma, C_RHG) are known and the assumptions behind the cited rock properties relationship match the engineering case being checked.

Assumptions

  • Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
  • The declared units match the field-unit constants used in the formula.
  • The cited formula applies to the selected petroleum engineering workflow.

Limitations

  • The calculation does not replace a full engineering model or operating procedure.
  • Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.

Common mistakes

  • Mixing unit systems without converting the inputs.
  • Using default example values as field recommendations.
  • Applying the formula outside the source assumptions.

Frequently asked questions

What inputs does the Sonic Porosity Raymer-Hunt-Gardner Method calculator need?

The calculation uses Sonic Log Transit Time Reading (Delta_t), Matrix Transit Time (Delta_t_ma), Raymer-Hunt-Gardner Empirical Constant (C_RHG). Enter values on the units shown beside each field.

What result does this calculator return?

The primary result is sonic porosity in fraction. The formula section shows the declared relationship, variables, and a reproducible default calculation.

What should I check before using the result?

Confirm the unit basis, source applicability, and input quality. The calculation does not replace a full engineering model or operating procedure. Mixing unit systems without converting the inputs.

Source and record status

Source metadata identifies the relationship implemented by the calculator. Check the cited edition, unit basis, and scope against the engineering case before operational use.

reviewedguidance published

Formation Evaluation and Petrophysics, Core Laboratories (2005)

Core Laboratories. 2005. Formation Evaluation and Petrophysics, Page 87.

Open source reference

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