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   https://doi.org/10.1038/s43017-023-00467-0  

   Weis, Dominique; Harpp, Karen S; Harrison, Lauren N; Boyet, Maud; Chauvel, Catherine; Farnetani, Cinzia G; Finlayson, Valerie A; Lee, Kanani_K M; Parai, Rita; Shahar, Anat; et al (September 2023, Nature Reviews Earth & Environment)
2. Linking lowermost mantle structure, core-mantle boundary heat flux and mantle plume formation

   https://doi.org/10.1016/j.pepi.2018.01.010  

   Li, Mingming; Zhong, Shijie; Olson, Peter (January 2018, Physics of the Earth and Planetary Interiors)
3. Coupled deep-mantle carbon-water cycle: Evidence from lower-mantle diamonds

   https://doi.org/10.1016/j.xinn.2021.100117  

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4. The root to the Galápagos mantle plume on the core-mantle boundary

   https://doi.org/10.26443/seismica.v1i1.197  

   Cottaar, Sanne; Martin, Carl; Li, Zhi; Parai, Rita (October 2022, Seismica)

   Ultra-low velocity zones (ULVZs) are thin anomalous patches on the boundary between the Earth's core and mantle, revealed by their effects on the seismic waves that propagate through them. Here we map a broad ULVZ near the Galápagos hotspot using shear-diffracted waves. Forward modelling assuming a cylindrical shape shows the patch is ~600 km wide, ~20 km high, and its shear velocities are ~25% reduced. The ULVZ is comparable to other broad ULVZs mapped on the core-mantle boundary near Hawaii, Iceland, and Samoa.  Strikingly, all four hotspots where the mantle plume appears rooted by these ‘mega-ULVZs’, show similar anomalous isotopic signatures in He, Ne, and W in their ocean island basalts. This correlation suggests mega-ULVZs might be primordial or caused by interaction with the core, and some material from ULVZs is entrained within the plume. For the Galápagos, the connection implies the plume is offset to the west towards the base of the mantle. 

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5. Low Melting Temperature of Anhydrous Mantle Materials at the Core‐Mantle Boundary

   https://doi.org/10.1029/2020GL089345  

   Kim, Taehyun; Ko, Byeongkwan; Greenberg, Eran; Prakapenka, Vitali; Shim, Sang‐Heon; Lee, Yongjae (October 2020, Geophysical Research Letters)

   Abstract One of the central challenges in accurately estimating the mantle melting temperature is the sensitivity of the probe for detecting a small amount of melt at the solidus. To address this, we used a multichannel collimator to enhance the diffuse X‐ray scattering from a small amount of melt and probed an eutectic pyrolitic composition to increase the amount of melt at the solidus. Our in situ detection of diffuse scattering from the pyrolitic melt determined an anhydrous melting temperature of 3,302 ± 100 K at 119 ± 6 GPa and 3,430 ± 130 K at the core‐mantle boundary (CMB) conditions, as the upper bound temperature. Our CMB temperature is approximately 700 K lower than the previous estimates, implying much faster secular cooling and higher concentrations of S, C, O, and/or H in the region, and nonlinear, advocating the basal magma ocean hypothesis. 

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