Comment and Reply on "Metamorphosed soils as stratigraphic indicators in deformed terranes: An example from the Eastern Alps"

Geochemistry of sericite deposits at the base of the paleoproterozoic aravalli supergroup, Rajasthan, India: Evidence for metamorphosed and metasomatised precambrian paleosol

“…Even in such cases, geochemical signatures have been found to be useful in identification of paleosols. However, it is of interest to note that application of geochemical signatures for identifying paleosols in highly deformed and metamorphosed terranes has led to a number of debates not only on their origin but also regarding their validity as good barometers of oxygen in atmosphere (Kallioski 1975(Kallioski , 1977Lewan 1977;Selverstone 1987, 1988;Williams 1988;Palmer et al 1989;Ohmoto 1996Ohmoto , 1997Holland and Rye 1997;Rye and Holland 1998). One of the main problems is how to distinguish the geochemical variations produced during subaerial weathering from those resulting from other alterations such as hydrothermal alterations in shear zones.…”

“…An integrated approach comprising study of field relations, petrography and compositional variations may together possibly lead to identification of paleosols with greater confidence in deformed and metamorphosed Precambrian terranes. Identification of paleosols in such terranes is helpful in understanding stratigraphic relations (Barrientos and Selverstone 1988), sedimentary facies of the supracrustal sequence (Williams 1988) and crustal evolution in a particular metamorphosed terrane (Retallack 1990). Metamorphosed paleosols give at least a qualitative understanding of PO 2 levels in the atmosphere of the past.…”