Penetrative calcretes and their stratigraphic implications

Multiple calcrete horizons previously considered representative of true subaerial exposure may, in fact, be false penetrative calcretes related to only one subaerial exposure event. Although penetrative calcrete horizons are not laterally traceable over long distances, they are very similar to surficial calcretes, are commonly found at sequences and/or lithologic boundaries (permeability anomalies), and can be easily misinterpreted in core borings as representing individual exposure events. Penetrative and surficial calcretes can be differentiated by the lower concentrations of insoluble Al and Fe in penetrative calcretes. -from Authors