Science - 16.08.2019

from oceanic lithosphere (mantled^13 C, high U-
Th/^3 He, low R/Ra) and pelagic sediments con-
taminated by high-^3 He/^4 He material (lowd^13 C,
low U-Th, high R/Ra) could explain trend B.
Helium is trapped in fluid inclusions during dia-
mond precipitation, likely caused by an inter-
action between a low-degree oxidized melt from
subducted material and ambient reduced mantle
or plume material ( 32 ). Several additional lines of
evidence support a high-^3 He/^4 He source, poten-
tially delivered by a mantle plume that may have
originated from the African Large Low Shear
Velocity Province ( 33 ). A clear increase in^3 He
concentrations and, to a lesser extent, in^4 He con-
centrations, is accompanied by higher^3 He/^4 He
ratios for the Collier-4 and Juina-5 diamonds
(Fig. 2, C and D). This observation requires that
the high-^3 He/^4 He source has higher He abun-
dances than reservoirs with low^3 He/^4 He ratios
and thus supports the presence of a primordial

(^3) He plume. A similar conclusion was reached
for fibrous lithospheric diamonds from Russia
( 34 ). Further, a high-^3 He/^4 He component could
be related to a Cretaceous mantle plume in the
Juina area. The contemporaneous formation of
alkaline rocks and the Trindade plume track
(32) with the young diamond formation age of a
sublithospheric Collier-4 diamond [101 ± 7 million
years ( 23 )] along with the kimberlite eruption
ages around 93 million years ago in the Juina
area ( 35 ) all provide evidence for a deep high-
(^3) He/ (^4) He source delivered by a plume. Trans-
portation of superdeep diamonds to shallower
depths also has been suggested to occur by a
mantle plume ( 22 ). Evidence from seismic tomog-
raphy indicates that this plume-related mantle
remains coupled to the lithosphere beneath
Brazil today ( 36 ).
The complexity of isotope compositions ob-
served in oceanic basalts has attracted devel-
opment of a variety of models to explain them.
Central to these models has been the problem
of constraining the heterogeneous He isotope
compositions of the OIB source, because these
compositions seem to be largely decoupled from
those of other radiogenic isotopes. Resolving this
issueiscritical,becauseHeinparticularhasbeen
used to define large-scale mantle structures ( 3 )
despite debate about the depth of the high-^3 He/
(^4) He source region tapped by OIB ( 1 , 6 – 17 ). The
He isotopic data for fluid inclusions in superdeep
diamonds presented here resolve this issue by
showing direct evidence that the high-^3 He/^4 He
source must be present in the deep mantle, beneath
a depth of 410 km. Further, the wide-ranging
Sr-Pb-C isotope compositions of the superdeep
diamond-forming fluids document the extreme
variability in the Earth’s transition zone due to
recycled crustal inputs. This recycled material is
also recorded by C-N-O isotopes in other super-
deep diamonds and their mineral inclusions
( 25 , 37 ) and clearly has the potential to generate
much of the isotopic variation found in OIBs.
Our results show that the transition zone is an
important heterogeneous reservoir sampled by
ascending plumes, ultimately forming OIBs with
less extreme isotope compositions due to mixing.
REFERENCES AND NOTES

1. C. Class, S. L. Goldstein,Nature 436 , 1107–1112 (2005).


2. A. Hofmann, inTreatise on Geochemistry, vol. 3, R. W. Carlson,
   Ed. (Elsevier Science, ed. 2, 2014), pp. 67–101.


3. D. Hilton, D. Porcelli, inTreatise on Geochemistry, vol. 2,
   R. W. Carlson, Ed. (Elsevier, 2003), pp. 327–353.


4. F. M. Stuart, S. Lass-Evans, J. G. Fitton, R. M. Ellam,Nature
   424 ,57–59 (2003).


5. D. W. Graham,Rev. Mineral. Geochem. 47 , 247–317 (2002).
   6. M. G. Jackson, J. G. Konter, T. W. Becker,Nature 542 ,
   340 – 343 (2017).
   7. H. M. Gonnermann, S. Mukhopadhyay,Nature 459 , 560– 563
   (2009).
   8. H. M. Gonnermann, S. Mukhopadhyay,Nature 449 , 1037– 1040
   (2007).
   9. D. Porcelli, G. Wasserburg,Geochim. Cosmochim. Acta 59 ,
   4921 – 4937 (1995).
   10. L. Kellogg, G. Wasserburg,Earth Planet. Sci. Lett. 99 , 276– 289
   (1990).
   11. R. D. van der Hilst, S. Widiyantoro, E. Engdahl,Nature 386 ,
   578 – 584 (1997).
   12. S. W. Parman,Nature 446 , 900–903 (2007).
   13. A. Meibomet al.,Earth Planet. Sci. Lett. 208 ,197– 204
   (2003).
   14. R. L. Christiansen, G. Foulger, J. R. Evans,Geol. Soc. Am. Bull.
   114 , 1245–1256 (2002).
   15. G. Foulgeret al.,Geophys. J. Int. 146 , 504–530 (2001).
   16. G. Foulger, D. Pearson,Geophys. J. Int. 145 ,F1–F5 (2001).
   17. D. L. Anderson,Proc. Natl. Acad. Sci. U.S.A. 95 , 4822– 4827
   (1998).
   18. S. Timmerman, M. Honda, D. Phillips, A. L. Jaques, J. W. Harris,
   Mineral. Petrol. 112 (suppl. 1), 181–195 (2018).
   19. D. Shelkov, A. Verchovsky, H. Milledge, C. Pillinger,Chem. Geol.
   149 , 109–116 (1998).
   20. M. D. Kurz, J. J. Gurney, W. J. Jenkins, D. E. Lott III,Earth
   Planet. Sci. Lett. 86 ,57–68 (1987).
   21. A. Thomsonet al.,Contrib. Mineral. Petrol. 168 ,1081
   (2014).
   22. M. J. Walteret al.,Science 334 ,54–57 (2011).
   23. G. P. Bulanovaet al.,Contrib. Mineral. Petrol. 160 ,489– 510
   (2010).
   24. Supplementary materials.
   25. A. Burnhamet al.,Earth Planet. Sci. Lett. 432 ,374– 380
   (2015).
   26. F. Kaminsky,Earth Sci. Rev. 110 , 127–147 (2012).


6. B. Harte, S. Richardson,Gondwana Res. 21 ,236– 245
   (2012).


7. A. Thomsonet al.,Lithos 265 , 108–124 (2016).


8. T. Hanyu, I. Kaneoka,Nature 390 , 273–276 (1997).


9. D. R. Hilton, G. M. McMurtry, R. Kreulen,Geophys. Res. Lett.
   24 , 3065–3068 (1997).


10. R. Burgess, L. Johnson, D. Mattey, J. Harris, G. Turner,Chem.
    Geol. 146 , 205–217 (1998).


11. A. R. Thomson, M. J. Walter, S. C. Kohn, R. A. Brooker,Nature
    529 ,76–79 (2016).


12. T. H. Torsvik, K. Burke, B. Steinberger, S. J. Webb,
    L. D. Ashwal,Nature 466 ,352–355 (2010).


13. M. Broadleyet al.,Geochem. Perspect. Lett. 8 ,26– 30
    (2018).


14. F. V. Kaminskyet al.,Lithos 114 ,16–29 (2010).


15. J. C. VanDecar, D. E. James, M. Assumpção,Nature 378 ,25– 31
    (1995).


16. M. Palot, D. Pearson, R. Stern, T. Stachel, J. Harris,Geochim.
    Cosmochim. Acta 139 ,26–46 (2014).


17. A. Stracke, M. Bizimis, V. J. Salters,Geochem. Geophys.
    Geosyst. 4 , 8003 (2003).

ACKNOWLEDGMENTS

P. Holden, X. Zhang, S. Zink, E. Kristianov, M. Regier, and M. Krebs

are thanked for analytical assistance.Funding:This research is

supported by AGRTP and Ringwood scholarships and an IAGC

Elsevier Ph.D. student research grant to S.T., ARC-DP140101976 to

M.H. and A.L.J., and a CERC to D.G.P.Author contributions:

S.T. carried out all the analyses and wrote the first version of

the paper, with the exceptions of six He sample analyses

carried out by M.H. and Raman analyses at ANU performed

by C.L.L. G.P.B., C.B.S., J.W.H., and E.T. supplied the samples.

All authors contributed to data discussions and the paper.

Competing interests:The authors declare no competing interests.

Data and materials availability:All data are available in the

main text or the supplementary materials.

SUPPLEMENTARY MATERIALS

science.sciencemag.org/content/365/6454/692/suppl/DC1

Materials and Methods

Figs. S1 to S5

Tables S1 to S4

Databases S1 to S4

References ( 39 – 71 )

31 March 2019; accepted 16 July 2019

10.1126/science.aax5293

Timmermanet al.,Science 365 , 692–694 (2019) 16 August 2019 3of3

Fig. 4. Trace-element patterns of fluid inclusions.Three different groups of patterns were
observed, revealing anomalies consistent with the influence of recycled material. Individual
patterns are shown in fig. S4.

RESEARCH | REPORT