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Various physicochemical conditions e.g., pressure, temperature, and degree of fractionation control the mafic magma composition during mantle melting and its emplacement in the crust. Constraining the composition of ancient mafic magmas can greatly aid to the understanding of the thermal condition of the mantle and the mechanics of the convective mantle throughout Earth's history. In this study we re-evaluate the mantle potential temperature (Tp) from Archean (3800Ma) to Proterozoic (563Ma) basalts derived from a depleted mantle from greenstone belts, and ophiolites assuming these are the direct product of upper mantle melting in an oceanic mantle condition. To calculate the Tp, a redox condition of Fe +3/FeTotal=0.1 is considered at the magma source. Tp values calculated from basaltic compositions whose ages are > 2800Ma reveal a hotter ambient mantle. Similarly, Tp values during the Proterozoic reveal presence of colder ambient mantle. However, we found the first evidence of colder ambient mantle during the Neoarchean (2800Ma-2500Ma) from different cratons worldwide, where the Tp values are significantly less (< 1500°C) than the previous published studies. Various petrological and geochemical studies have pointed to a major geodynamic change during the Neoarchean period e.g., a global peak in andesitic crust production, occurrences of high and intermediate metamorphism in rock record, emergence of collisional fold belt, first appearance of passive margin, higher plate velocity, supply of vast amount of sediments to ocean floor, and emergence of Sanukitoids; all of which require operation of plate tectonics during the Neoarchean. On the other hand, a transition from a mantle dominated by Tp >1500°C, to one with Tp