HINDSIGHT HERESY

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Hindsight Heresy
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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, 295308 (2003). 2. Torsvik, T.H.
et al. 2006. Large igneous provinces generated
from the margins of the large low-velocity
provinces in the deep mantle. GJI 167,
14471460. 3. Burke, K. et al. Plume generation
zones at the margins of large low shear velocity
provinces on the coremantle boundary. EPSL 265,
4960 (2008). 4. Lithgow-Bertelloni, C.,
Richards, M.A., 1998. The dynamics of Cenozoic
and Mesozoic plate motions. Rev. Geophys. 36,
2778. 5. Cottaar, S., B. Romanowicz, An unsually
large ULVZ at the base of the mantle near Hawaii,
EPSL, 355-356, 213-222, 2012. 6. Courtier, A. M.
and 14 others. Correlation of seismic and
petrologic thermometers suggests deep thermal
anomalies beneath hotspots. EPSL 264, 308-316.
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Ridge, slab related
100 km depth
Using the same parameters as Burke, the
correlation of hotspots backtracked LIPs with
tomography is higher for the uppermost than for
the lowermost mantle
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Most hotspots are in broad ridge-related
LVAs LIPs some hotspots started at edges of
slabs
Slabs in TZ
11 hotspots on edges
Ridge-related LVAs
18 hotspots
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Hotspots correlate with upper mantle LVAs
6 aberrant hotspots
(outside of plate boundary related low wavespeed
areas)
Plt10-8
100 km depth
true within-plate hotspots are underlain by
average or fast mantle at 100 km depth.
14 aberrant hotspots
Core-mantle boundary (CMB)
P1.47x10-7
Burke et al.
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There is a strong anticorrelation between the
inferred positions of plate divergence, ridges,
hotspots and LIP initiation subduction zones
over the last 250 Myrs and high wavespeed
features in and just below the TZ.
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Plates move over less dense hotter mantle as
they move away from ridge
ridges
Constrains thermal gradient
Constrains melt content
Cross-over
anisotropy
Near-ridge mantle
This explains seafloor flattening residual
bathymetry