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The Sapucaia Greenstone Belt, located within the E-W boundary zone between the Carajás and Rio Maria tectonic domains of the Carajás Province, in the Amazonian Craton, represents a deformed and discontinuous meta-volcano-sedimentary sequence. It comprises: (i) metaultramafic unit with rocks derived from olivine cumulate (forsterite-serpentine and forsterite-tremolite-chlorite schists) and komatiite basalt and komatiite (tremolite-chlorite and chlorite-actinolite schists); (ii) metamafic unit derived from tholeiite basalts and gabbros (hornblende-plagioclase amphibolite, actinolite schist, dolomite-hornblende schist, metagabbros); (iii) meta-intermediate unit (metaandesite and metadacite); (iv) metasedimentary unit with muscovite, biotite, chloritequartz, and (almandine)-muscovite-biotite schists. Rocks derived from olivine cumulate have high MgO contents (27.5 to 40.40 wt.%), Al 2 O 3 /TiO 2 = 24.88 -35.50, CaO/Al 2 O 3 = 0.02 -0.93, La /Yb N = 1.5, low ΣREE values (1.0 to 3.7 ppm), lack of significant Eu anomalies (Eu/Eu* = 0.7 to 1.2), and negative Ce anomalies (Ce/Ce* = 0.1 to 0.4). Komatiite basalt and komatiite (MgO = 12.6 to 25.