Glacigenic clast fabrics: genetic fingerprint or wishful thinking?

The interpretation of glacigenic diamictons is a subjective process, for wh ich quantitative support is frequently sought from parameters such as clast shape and fabric. It has been widely suggested that different glacigenic d iamicton facies possess distinct clast-fabric signatures. This paper examin es this concept using a data set of 111; clast fabrics, and a synthesis of published results. Eigenvalues are calculated and compared for a variety se dimentary facies. It is concluded that clast fabric alone is not able to di scriminate between different glacigenic facies, and it is argued that clast fabric offers little quantitative support in the interpretation of glacige nic sediments. It is suggested, therefore, that although clast fabric may c ontinue to have a role as an indicator of relative strain at specific sites , its use in the discrimination of glacigenic facies is limited. Consequent ly, we should be much more selective in undertaking such analyses in the fu ture. Copyright (C) 1999 John Wiley & Sons, Ltd.