The paper presents the results of the study of thin differentiated Mesoarchean komatiite lava flows from the Koikary and Sovdozero greenstone domains. Several zones were recognized in the section of differentiated lava flows: autobreccia, spinifex texture of olivine and pyroxene types, massive, cumulate (ortho- and mesocumulates), as well as the lower chilled contact at the basement of the flow. The stratification of the lava flows is due to magmatic differentiation in situ coupled with the continuing injection of more molten rock until the stage of complete crystallization.