Abstract Investigating the Earth’s mantle via major and trace element concentrations identified a geochemically heterogenous mantle. By studying radiogenic isotope systems, it was possible to understand mantle’s evolution and depletion events through time. Some studies on peridotites from slow to ultra-slow spreading ridges display extreme radiogenic Hf and Nd isotope compositions. The associated ancient melt depletion questions the average depletion of the mantle. Here, we present new Hf and Nd data from abyssal peridotite clinopyroxenes from the slow spreading American-Antarctic Ridge. We combine trace element and isotopic data to investigate the local composition of the mantle beneath the ridge. We observed a residual character of the peridotites with recent melt-rock interaction during ascent below the ridge. With the focus on the isotopic composition, the peridotites spread at the depleted end of the MORB field and preserve a record of recent mantle depletion. In conclusion, the peridotites do not reveal an ultradepleted mantle beneath the American-Antarctic Ridge. Though they do show a residual character and are of importance to understand global mantle composition.

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