If gas hydrate is instead acting as a component of the load bearing sediment framework, then the original dry sediment calculations must be altered to account for the changes in the effective solid phase (mineral plus hydrate) moduli and sediment porosity. The presence of gas hydrate reduces the porosity of the original sediment (j) to a new value (¡> = (f) — Ch.
The effective mineral modulus for the gas hydrate/sediment solid phase is calculated from Equation (7) where ft should be replaced by
1 - <t> + Ch and gas hydrate should be treated as an additional mineral component with fraction fh given by h = , C"r • (ID
The elastic moduli and velocities of the water saturated gas hydrate bearing sediments are then calculated using Gassmann's equations (5) where porosity and bulk and shear moduli of the solid phase are replaced with the model-appropriate values.
This model is appropriate for any porosity and any fractional filling of the pore space by gas hydrate.
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