cig_2020_poster_emmanuel_njinju.pdf

The impact of a plume head beneath the lithosphere generally results in intense melting of plume materials, producing large igneous provinces (LIPs; White & McKenzie, 1995) such as in the Eastern Branch of the East African Rift (EAR; Alayew & Gibson, 2009). However, the Western Branch of the EAR is characterized by limited and sparse magmatism and the melt source is contentious. Geochemical studies of past eruptions of the Rungwe Volcanic Province (RVP) in the Western Branch, indicate plume signatures (elevated mantle potential temperatures; Rooney et al., 2011 and high 3He/4He; Hilton et al., 2011). The plume signatures of the RVP remain enigmatic, mainly because the volcanism is highly localized, unlike the LIP in the Eastern Branch. We use 3D geodynamics models to investigate plume-lithosphere interactions beneath the RVP, to better understand the sources of the enigmatic plume signatures.