Method For Predicting Differences In Subsurface Conditions

A method for predicting differences in subsurface conditions useful in 4D applications. In an example embodiment of the method, at least one layer is defined in a data volume representing a first subsurface condition such as shale volume fraction (104). An exhaustive search methodology is then performed over a second subsurface condition such as pressure or saturation for some or all of the first subsurface condition data points (106) based on a data fit of synthetic geophysical data to measured geophysical data. The exemplary method may additionally comprise performing a statistical analysis to determine whether the error in data fit is significantly reduced (110) if one of the layers is divided into two or more layers (108). The layer is divided into multiple layers (114) if the error is significantly reduced (112). In this manner, the measured survey data are inverted to predict values of the second subsurface condition.