Gassmann Inverse Dry Modulus & Fluid Substitution Wave State Calculator

Use this endpoint when you need to perform rigorous Gassmann-equation-based fluid substitution on an explicit rock-physics model with known mineral, frame, and fluid properties. It is the right choice for reservoir characterization, 4D seismic feasibility studies, AVO modeling, and CO2 sequestration impact prediction where you have laboratory or log-derived elastic moduli and need to predict seismic response under a different fluid scenario. Prefer this over empirical velocity-porosity transforms when you have full Biot-Gassmann inputs available.

• Input values outside allowed ranges (e.g. porosity > 0.6 or < 0.01) return validation errors
• Physically inconsistent inputs (e.g. saturated bulk modulus exceeding mineral bulk modulus) may cause computation failure or unphysical results
• Missing required fields return schema validation errors
• Negative or zero moduli values rejected by min constraints
• Fluid bulk modulus exceeding mineral bulk modulus may produce unphysical dry-frame moduli