The slowing factor s is 4, and the correlation includes all 12 harmonic degrees

Examples of “Hindsight Heresy” in which a hypothesis is constructed after looking at a data set, and then using the same data to support and test the hypothesis, to prune the data or change parameters (Burke 2008; Torsvik at al. 2006; Lithgow-Bertelloni & Richards 1998; Courtillot et al 2003; Coutier et al. 2007; etc.). 1. Courtillot, V. et al. Three distinct types of hotspots in the Earth's mantle. Earth Planet. Sci. Lett. 205, (2003). 2. Torsvik, T.H. et al Large igneous provinces generated from the margins of the large low-velocity provinces in the deep mantle. GJI 167, 1447– Burke, K. et al. Plume generation zones at the margins of large low shear velocity provinces on the core–mantle boundary. EPSL 265, 49–60 (2008). 4. Lithgow-Bertelloni, C., Richards, M.A., The dynamics of Cenozoic and Mesozoic plate motions. Rev. Geophys. 36, 27– Cottaar, S., B. Romanowicz, An unsually large ULVZ at the base of the mantle near Hawaii, EPSL, , , Courtier, A. M. and 14 others. Correlation of seismic and petrologic thermometers suggests deep thermal anomalies beneath hotspots. EPSL 264,

Pacific hotspots & backtracked plateaus Atlantic hotspots Indian Ocean hotspots & plateaus Present day ridge-related low wavespeed regions correspond to red-brown age regions

Even the largest igneous events can be explained by extracting magma from the upper 200 km Area covered, insulated & polluted by Pangea LIPs

LIPs & hotspots are associated with continental breakup reconstruction at ~ 30 Ma dual volcanism –on breakup –~ 30 Myr later oceanic plateaus form ~ 1,000 km offshore = rising of delaminated root?

The slowing factor s is 4, and the correlation includes all 12 harmonic degrees

The integrated density under many ridges is high Seafloor flattening is due to lateral density gradients below 200 km Ridges are fed by upwellings from the transition zone

Even the largest igneous events can be explained by extracting magma from the upper 200 km Vs 80 km depth

6 ‘aberrant’ hotspots 14 ‘aberrant’ hotspots P=1.47x10 -7 Burke et al. (“outside of plate boundary related low wavespeed areas) true within-plate hotspots are underlain by average or fast mantle at 100 km depth. 100 km depth Core-mantle boundary (CMB) P<10 - 8

100 km depth Ridge, slab related Using the same parameters as Burke, the correlation of hotspots & backtracked LIPs with tomography is higher for the uppermost than for the lowermost mantle