Fig. 4: Geochemical evidence for removal of cratonic keel.
From: Rift-induced disruption of cratonic keels drives kimberlite volcanism
Major kimberlite fields in South Africa (a) and North America (b) show abrupt shifts, identified using conjugate partitioned recursion (grey lines; Methods), from lithospheric (ϵNdi −6 to −20) to mantle (ϵNdi 0 to +5) Nd isotope compositions. Note that MARID denotes the mica–amphibole–rutile–ilmenite–clinopyroxene endmember representing metasomatized lithospheric mantle (Methods). Data sources provided in Extended Data Figs. 10 and 11; shaded band in a denotes independent evidence for removal of about 40 km of keel40.
