Fig. 2.
Relationship between the depth of the weathered-to-fractured interface and the depth where the reactive zone is inferred by the stratified reactivity framework. Data of the weathered and fractured interface depth were provided by the French Geological Survey (6). Depths of the reactive zone were determined by examining the depth of a water parcel at the time it enters the reactive zone, τenter, and calculated via the stratified reactivity framework. The interface of the weathered and fractured zone thickness has been found to be reactive in several crystalline aquifers in Brittany, France (45). This supports the validity of the stratified reactivity framework.