Convert Micrometre squared to Millidarcy

Convert Micrometre squared (µm²) to Millidarcy (mD) instantly and accurately.

Micrometre squared (µm²)
Millidarcy (mD)

Conversion Formula

mD = µm² × 1013.25

About Micrometre squared

The micrometre squared (µm²) equals 10⁻¹² m², the SI-consistent permeability unit used in European reservoir standards and ISO documents. 1 µm² ≈ 1.0133 D - numerically close to but distinct from the darcy. Clean gravel: 1-10 µm²; clean sandstone: 10⁻³-0.1 µm². 1 µm² = 10⁶ nm² = 10⁻⁶ mm².

About Millidarcy

The millidarcy (mD) equals 10⁻³ D ≈ 9.869 × 10⁻¹⁶ m², the everyday unit in petroleum reservoir engineering worldwide. Conventional sandstone reservoirs: 1-1 000 mD; carbonate reservoirs: 0.1-100 mD; economic gas recovery typically requires k ≥ 0.1 mD. Permeameter and well-test reports give results in mD. 1 mD = 10⁻³ D = 10³ µD.

Quick Reference Table

Micrometre squared (µm²)Millidarcy (mD)
1 µm²1013.25 mD
2 µm²2026.5 mD
5 µm²5066.25 mD
10 µm²10132.5 mD
25 µm²25331.2 mD
50 µm²50662.5 mD
100 µm²101325 mD

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