Chapter 11: AVO Anomalies From Clean, Wet Sands
In this chapter, we describe two cose histories in which AVO anomalies were drilled and found to correspond to thick, porous, clean, wet sands. Modeling confirms that a porous, clean, wet sand can produce an increase in amplitude with offset resembling that produced by gas sands.
It is important to know the Vp/Vs ratio of the target and surrounding rocks to a reasonable degree of accuracy, as Vp/Vs ratios are a major determiner of AVO response.
Clean, porous, wet sands can cause AVO anomalies similar to those caused by gas sands in less porous rocks.