"..No relict slab underlies the extinct northern Kamchatka volcanic
arc <...> From the tectonic and volcanic evolution of Kamchatka over
the past 10 Myr (refs 3, 4–5) we infer that at least two episodes of
catastrophic slab loss have occurred.. <....> Removal of lithospheric
mantle is commonly discussed in the context of a continental
collision, but our findings imply that episodes of slab detachment and
loss are also important agents in the evolution of oceanic convergent
margins.

-----------------------------------------------
Exhilharated by the thrill of discovery that no subducting slab
underlies the extinct northern Kamchatka volcanic arc, and paddling
himself with excitement, our bold convectioneer cites this absence as
direct proof for catastrophic slab loss, proposing avalanches of
subducting slabs into the mantle for good measure.
http://tinyurl.com/3qlj78
Commenting on findings in Nature, team leader Rubbery Trolley-Dosser
said: "Now you see 'em, now you don't.  It's like fairies at the
bottom of the garden, everyone knows they are invisible so the fact
that you don't see them is overwhelming direct proof for their
presence.  With future research we hope to be able to document more
areas where slabs are not present, thus confirming our findings of
catastrophic slab loss into the mantle.  We are excited by the
prospect that this could put an unprecedented new perspective on the
Atlantic and Indian and Oceans, and open up an entirely new avenue for
research."
http://users.indigo.net.au/don/nonsense/rubber.html#faeries
------------------------------------------------

With no apologies to Nature:-
-----------------------------------
evidence for catastrophic slab loss:
"In the northwest Pacific Ocean, a sharp corner in the boundary
between the Pacific plate and the North American plate joins a
subduction zone running along the southern half of the Kamchatka
peninsula1 with a region of transcurrent motion along the western
Aleutian arc1, 2. Here we present images of the seismic structure
beneath the Aleutian–Kamchatka junction and the surrounding region,
indicating that: the subducting Pacific lithosphere terminates at the
Aleutian–Kamchatka junction; no relict slab underlies the extinct
northern Kamchatka volcanic arc; and the upper mantle beneath northern
Kamchatka has unusually slow shear wavespeeds. From the tectonic and
volcanic evolution of Kamchatka over the past 10 Myr (refs 3, 4–5) we
infer that at least two episodes of catastrophic slab loss have
occurred. About 5 to 10 Myr ago, catastrophic slab loss shut down
island-arc volcanic activity north of the Aleutian–Kamchatka junction.
A later episode of slab loss, since about 2 Myr ago, seems to be
related to the activity of the world's most productive island-arc
volcano, Klyuchevskoy6. Removal of lithospheric mantle is commonly
discussed in the context of a continental collision, but our findings
imply that episodes of slab detachment and loss are also important
agents in the evolution of oceanic convergent margins."
http://www.nature.com/nature/journal/v418/n6899/full/nature00973.html
------------------------------------
...which should know better than to publish wet cardboard like this.