Instrumental neutron activation analysis of ferromanganese oxide encrustations of Indian Ocean by the k(0) NAA method

Three ferromanganese crusts from different locations of the Indian Ocean we re analysed by neutron activation analysis using the k(0) method (k(0) NAA method) for studying the distribution of some trace elements along with Fe and Mn. Another crust from the Lau basin of the Pacific Ocean was investiga ted for comparison of the influence of different oceanic conditions on the trace element distributions in ferromanganese crusts. Variation in Co conce ntration along with the Mn/Fe ratio were discussed in terms of the hydrogen ous/hydrothermal nature of the crusts. The normalised REE content was used to identify possible anomalies. The observed Ce anomaly is discussed in the light of the depositional environment. The precision and accuracy of the m ethod were confirmed by measuring the elemental concentrations in a USGS no dule standard NOD A-1.