One of the tasks frequently performed in hydrocarbon-reserve calculation is the determination of the net-sand thickness, the total thickness of the sand layers in a package of alternating sands and shales. In a Class-III environment, in particular, such a sand-shale sequence sandwiched between shales can lead to prominent reflections. If the gross-sand thickness (in the following I also use the term “target thickness”) is less than the tuning thickness and the wavelet is zero-phase, then the peak amplitude, trough amplitude, or a combination of both are frequently used to estimate the net-sand thickness. Other methods need to be employed if the gross-sand thickness exceeds the tuning thickness.

You do not currently have access to this article.