Dictionary:Shale baseline

{{#category_index:S|shale baseline}} 1. A line drawn through the minimum deflections characteristic of impermeable shales on an SP log (see Figure S-17), which is used as the reference in making measurements to determine the characteristics of sands and their formation waters. Compare sandline and see also SP and base-line shift. 2. A line drawn through the characteristic of thick shales on the gamma-ray log.