Regolith

Regolith 

Darnley et al. (1995) used the term 'regolith', which is a collective term, and should have not been used in such a reference work.  Further, Butt and Zeegers (1992) have made the same mistake and used it in another applied geochemistry reference handbook.

  

Definition of 'regolith' as given by:

 

(a) K.K.E. Neundorf, J.P. Mehl Jr. & J.A. Jackson (2011, p.544) in the revised Fifth Edition of the 'Glossary of Geology' (American Geosciences Institute):  "A general term for the layer or mantle of fragmental and unconsolidated rock material, whether residual or transported and of highly varied character, that nearly everywhere forms the surface of the land and overlies or covers the bedrock. It includes rock debris of all kinds, volcanic ash, glacial drift, alluvium, loess and eolian deposits, vegetal accumulations, and soil", and

 

(b) C.R.M. Butt. & H. Zeegers (1992, p.542) in the handbook 'Regolith exploration geochemistry in tropical and subtropical terrains (G.J.S. Govett, Series Editor, of Handbook of Exploration Geochemistry, Vol. 4. Elsevier Scientific Publishing Co., Amsterdam, 607 pp.):  “The entire unconsolidated and secondarily cemented cover that overlies the more coherent bedrock and that has been formed by the weathering, erosion, transport and/or deposition of older material. The regolith thus includes fractured and weathered basement rocks, saprolites, soils, organic accumulations, glacial deposits, colluvium, alluvium, evaporitic sediments, loess and aeolian deposits. May be subdivided into a lower unit, the saprolith, and an upper unit, the pedolith”.

 

It is quite apparent from the above definitions of 'regolith' that this is a term that should not be used in the Global Geochemical Baselines project, the aim of which is to develop a global Geochemical Reference Network for residual soil, stream sediment, stream water, overbank sediment, and floodplain sediment sensu stricto.