ABSTRACT
A first problem of comprehending and comparing different estimates of rates of denudation is that they are often reported in different forms. The basis of B. P. Ruxton and I. McDougall's approach to estimating rates of denudation in Papua was that, if a dissected volcanic landscape possessed earlier or 'original' forms that could be reconstructed and dated by potassium-argon dating, then, by measuring the volume of material removed, denudation rates could be calculated. The use of direct instrumentation to determine rates of chemical denudation has centred on two techniques: the micro-erosion meter and rock tablets. J. Crowther has attempted an evaluation of the relative results obtained by the rock tablet and water hardness methods for determining chemical denudation rates on karst surfaces. The first category causes chemical alteration of the rock while the second causes rock breakdown without significant alteration of minerals.
