File:GSG GLA FIG 16 05.jpg

English: Figure.16.5. Explanation of the development of caliche. A traces the stages in its development through time in section. Stage 1, at the initial stage only nodules form but as time proceeds the nodules coalesce into pillars if the muds are mudcracked or into larger nodules if not. Stage 3 occurs when the pillars and nodules grow into a massive bed; and stage 4 occurs when the massive bed no longer lets water through and pools appear on the surface in which pisoliths form. B, provides an explanation for the growth of caliche; d refers to the depth to which percolation of the rainwater normally goes. C, the development of thick beds of stage 1 or 2 etc occurs when there is a continous addition of sediment to the surface, so that the depth of water percolation dl, and the zone of nodule formation Z1 rises as the sediment is added. The surface does not mature because the process is not operating in the same zone (Z1) for a sufficient length of time.

From: Lawson, J.D. and Weedon, D.S. (editors). 1992. Geological excursions around Glasgow & Girvan. Glasgow : Geological Society of Glasgow.