Natural weathering of certain karst limestones produces layered and largely continuous cave deposits of clays covering the past few million years. Climatological changes throughout this period are largely responsible for the variations of elements present in the clays at minor and trace levels. Neutron activation analysis, with appropriate clustering and statistical analysis, brings together those clays of close analytical parity and thus presumed similar climatological origin. The technique affords a new method of examining related sites for phases of correspondence and, in conjunction with disequilibrium dating and magnetic work, could be of considerable value in Pleistocene studies. The paper describes the work completed to date from the several hundred analyses covering four sites with extensive sediment deposits. -- AATA