Ann: Mukuyu-2 Drilling Update, page-312

Very good reference material. Although I'm not sure I fully agree with the following: "In zones of high effective porosity and permeability, the rocks will initially be flushed, then return to their native state soon after drilling, with little or no gas liberated. This causes a zone with minimal gas show when drilled to appear productive on electric logs or when later tested.

When the permeability is high, we should expect deep invasion of mud mulitrate into a formation, which can make the deep Laterolog resistivity reading look low (water mainly) and may even affect an Induction log, which as deeper radius of investigation compared to a Laterolog.