Patent ID: 8831885

Claim:
A method of estimating a value of a porosity of an earth formation in a gas-bearing interval, the earth formation comprising the gas-bearing interval and a liquid-bearing interval, the method comprising: using an acoustic tool for making a measurement indicative of a porosity of the earth formation in the gas-bearing interval, the gas-bearing interval comprising: a first solid component having a first value of an acoustic property affecting the measurement, and a second solid component having a second value of an acoustic property affecting the measurement, wherein the first value is different than the second value; and using an at least one processor to estimate the value of the porosity in the gas-bearing interval using: (i) the measurement made by the acoustic tool, and (ii) an estimated value of the acoustic property for the gas-bearing interval determined using a fractional volume of the second solid component and a correlation between acoustic property values and corresponding fractional volumes of the second solid component in the liquid-bearing interval.