Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes

Summary Trace-element data for mid-ocean ridge basalts (MORBs) and ocean island basalts (OIB) are used to formulate chemical systematics for oceanic basalts. The data suggest that the order of trace-element incompatibility in oceanic basalts is Cs ≈ Rb ≈ (≈ Tl) ≈ Ba(≈ W) > Th > U ≈ Nb = Ta ≈ K > La > Ce ≈ Pb > Pr (≈ Mo) ≈ Sr > P ≈ Nd (> F) > Zr = Hf ≈ Sm > Eu ≈ Sn (≈ Sb) ≈ Ti > Dy ≈ (Li) > Ho = Y > Yb. This rule works in general and suggests that the overall fractionation processes operating during magma generation and evolution are relatively simple, involving no significant change in the environment of formation for MORBs and OIBs. In detail, minor differences in element ratios correlate with the isotopic characteristics of different types of OIB components (HIMU, EM, MORB). These systematics are interpreted in terms of partial-melting conditions, variations in residual mineralogy, involvement of subducted sediment, recycling of oceanic lithosphere and processes within the low velocity zone. Niobium data indicate that the mantle sources of MORB and OIB are not exact complementary reservoirs to the continental crust. Subduction of oceanic crust or separation of refractory eclogite material from the former oceanic crust into the lower mantle appears to be required. The negative europium anomalies observed in some EM-type OIBs and the systematics of their key element ratios suggest the addition of a small amount (⩽1% or less) of subducted sediment to their mantle sources. However, a general lack of a crustal signature in OIBs indicates that sediment recycling has not been an important process in the convecting mantle, at least not in more recent times (⩽2 Ga). Upward migration of silica-undersaturated melts from the low velocity zone can generate an enriched reservoir in the continental and oceanic lithospheric mantle. We propose that the HIMU type (eg St Helena) OIB component can be generated in this way. This enriched mantle can be re-introduced into the convective mantle by thermal erosion of the continental lithosphere and by the recycling of the enriched oceanic lithosphere back into the mantle.

[1]  G. Hanson.  Geochemical evolution of the suboceanic mantle , 1977, Journal of the Geological Society.

[2]  A. Hofmann,et al.  Sr and Nd isotope geochemistry of oceanic basalts and mantle evolution , 1982, Nature.

[3]  P. Vidal,et al.  Core Formation: Catastrophic or continuous? Sr and Pb isotope geochemistry constraints , 1978 .

[4]  E. Nakamura,et al.  The influence of subduction processes on the geochemistry of Japanese alkaline basalts , 1985, Nature.

[5]  A. Hofmann,et al.  Nb and Pb in oceanic basalts: new constraints on mantle evolution , 1986 .

[6]  M. Menzies,et al.  Nd and Sr isotope geochemistry of hydrous mantle nodules and their host alkali basalts: implications for local heterogeneities in metasomatically veined mantle , 1980 .

[7]  E. R. Oxburgh,et al.  Mid‐ocean ridges and geotherm distribution during mantle convection , 1968 .

[8]  V. Murthy,et al.  Sr and Nd Isotopic Composition of the Jacupiranga Carbonatite , 1985, The Journal of Geology.

[9]  S. Hart,et al.  Sr, Nd and Pb isotopic and REE geochemistry of St. Paul's Rocks: the metamorphic and metasomatic development of an alkali basalt mantle source , 1984 .

[10]  R. Carlson,et al.  Regional Middle Proterozoic enrichment of the subcontinental mantle source of igneous rocks from central Montana , 1987 .

[11]  F. Albarède,et al.  Isotope and trace element geochemistry of Colorado Plateau volcanics , 1986 .

[12]  A. Provost,et al.  Topology in isotopic multispace and origin of mantle chemical heterogeneities , 1987 .

[13]  A. E. Ringwood,et al.  Majorite partition behavior and petrogenesis of the Earth's upper mantle , 1987 .

[14]  E. Watson,et al.  PARTITIONING OF U, Pb, Cs, Yb, Hf, Re AND Os BETWEEN CHROMIAN DIOPSIDIC PYROXENE AND HAPLOBASALTIC LIQUID , 1987 .

[15]  C. Langmuir,et al.  Ridge Subduction and Forearc Volcanism: Petrology and Geochemistry of Rocks Dredged from the Western Solomon Arc and Woodlark Basin , 1987 .

[16]  Stephen H. Richardson,et al.  Correlated Nd, Sr and Pb isotope variation in Walvis Ridge basalts and implications for the evolution of their mantle source , 1982 .

[17]  P. J. Patchett,et al.  Importance of the Lu-Hf isotopic system in studies of planetary chronology and chemical evolution , 1983 .

[18]  S. Hart.  A large-scale isotope anomaly in the Southern Hemisphere mantle , 1984, Nature.

[19]  J. A. Philpotts,et al.  Phenocryst-matrix partition coefficients for K, Rb, Sr and Ba, with applications to anorthosite and basalt genesis , 1970 .

[20]  D. McKenzie,et al.  The Generation and Compaction of Partially Molten Rock , 1984 .

[21]  F. Frey,et al.  Trace element and isotopic geochemistry of lavas from Haleakala Volcano, east Maui, Hawaii: Implications for the origin of Hawaiian basalts , 1985 .

[22]  C. Hawkesworth,et al.  Evidence from the Parana of south Brazil for a continental contribution to Dupal basalts , 1986, Nature.

[23]  D. Clague,et al.  Geochemistry of tholeiitic and alkalic lavas from the Koolau Range, Oahu, Hawaii: Implications for Hawaiian volcanism , 1984 .

[24]  R. K. O’nions,et al.  Identification of recycled continental material in the mantle from Sr, Nd and Pb isotope investigations , 1982 .

[25]  P. W. Gast.  Trace element fractionation and the origin of tholeiitic and alkaline magma types , 1968 .

[26]  R. Duncan,et al.  Plume versus lithospheric sources for melts at Ua Pou, Marquesas Islands , 1986, Nature.

[27]  R. Armstrong,et al.  Radiogenic isotopes: the case for crustal recycling on a near-steady-state no-continental-growth Earth , 1981, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[28]  K. Jochum,et al.  The solar-system abundances of Nb, Ta, and Y, and the relative abundances of refractory lithophile elements in differentiated planetary bodies , 1986 .

[29]  H. Newsom,et al.  Siderophile and chalcophile element abundances in oceanic basalts, Pb isotope evolution and growth of the Earth's core , 1986 .

[30]  P. Stille,et al.  Pb, Sr, Nd, and Hf isotopic constraints on the origin of Hawaiian basalts and evidence for a unique mantle source , 1986 .

[31]  Robert W. Nesbitt,et al.  Geochemical characteristics of mid-ocean ridge basalts , 1979 .

[32]  P. Vidal,et al.  Large mantle heterogeneity beneath French Polynesia , 1984, Nature.

[33]  Y. Muramatsu.  Geochemical investigations of kimberlites from the Kimberley area, South Africa , 1983 .

[34]  J. Kramers.  Lead and strontium isotopes in Cretaceous kimberlites and mantle-derived xenoliths from Southern Africa , 1977 .

[35]  Shen-su Sun,et al.  Lead isotopic study of young volcanic rocks from mid-ocean ridges, ocean islands and island arcs , 1980, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[36]  W. McDonough,et al.  RB and CS in the Earth and Moon , 1987 .

[37]  D. Wood,et al.  Role of subducted sediment in the genesis of ocean-island basalts: Geochemical evidence from South Atlantic Ocean islands , 1986 .

[38]  R. Kay.  Zone refining at the base of lithospheric plates: A model for a steady-state asthenosphere , 1979 .

[39]  J. Kramers,et al.  Can Kimberlites be generated from an ordinary mantle? , 1981, Nature.

[40]  G. Hanson,et al.  Evolution of the mantle: Geochemical evidence from alkali basalt , 1975 .

[41]  B. Dupré,et al.  Pb–Sr isotope variation in Indian Ocean basalts and mixing phenomena , 1983, Nature.

[42]  S. Taylor,et al.  The continental crust: Its composition and evolution , 1985 .

[43]  D. Clague,et al.  Petrology and Trace Element Geochemistry of the Honolulu Volcanics, Oahu: Implications for the Oceanic Mantle below Hawaii , 1982 .

[44]  B. Hager,et al.  Mantle convection and the state of the earth's interior , 1987 .

[45]  W. White,et al.  The origin of Samoa: new evidence from Sr, Nd, and Pb isotopes , 1987 .

[46]  S. Goldstein,et al.  Nd, Sr and Pb isotopic systematics in a three-component mantle: a new perspective , 1982, Nature.

[47]  R. Thompson,et al.  An assessment of the relative roles of crust and mantle in magma genesis: an elemental approach , 1984, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[48]  A. Nicolas.  A Melt Extraction Model Based on Structural Studies in Mantle Peridotites , 1986 .

[49]  J. Blenkinsop,et al.  Nd and Sr isotopic compositions of East African carbonatites: Implications for mantle heterogeneity , 1987 .

[50]  D. Wood,et al.  Elemental and Sr isotope variations in basic lavas from Iceland and the surrounding ocean floor , 1979 .

[51]  C. R. Clement,et al.  Geochemical character of Southern African kimberlites; a new approach based on isotopic constraints , 1985 .

[52]  D. Clague,et al.  Geochemistry of diverse basalt types from Loihi Seamount, Hawaii: petrogenetic implications , 1983 .

[53]  D. Green,et al.  Integrated Models of Basalt Petrogenesis: A Study of Quartz Tholeiites to Olivine Melilitites from South Eastern Australia Utilizing Geochemical and Experimental Petrological Data , 1978 .

[54]  M. O'hara,et al.  Geochemical evolution in an advancing, periodically replenished, periodically tapped, continuously fractionated magma chamber , 1981, Journal of the Geological Society.

[55]  M. McCulloch,et al.  The origins of ultrapotassic rocks as inferred from Sr, Nd and Pb isotopes , 1986 .

[56]  B. Doe,et al.  Plumbotectonics-the model , 1981 .

[57]  M. Menzies,et al.  Mantle enrichment processes , 1984, Nature.

[58]  P. W. Gast,et al.  Lead isotope compositions and uranium decay series disequilibrium in recent volcanic rocks , 1968 .

[59]  L. Atalla,et al.  Trace Element and Strontium Isotope Constraints on the Origin and Evolution of Paraná Continental Flood Basalts of Santa Catarina State (Southern Brazil) , 1985 .

[60]  W. White.  Sources of oceanic basalts: Radiogenic isotopic evidence , 1985 .

[61]  Donald L. Turcotte,et al.  Implications of a two-component marble-cake mantle , 1986, Nature.

[62]  M. Tatsumoto,et al.  Partition coefficients of Hf, Zr, and ree between phenocrysts and groundmasses , 1984 .

[63]  D. L. Anderson.  Hotspots, polar wander, Mesozoic convection and the geoid , 1982, Nature.

[64]  E. Stolper,et al.  Geochemical Consequences of Melt Percolation: The Upper Mantle as a Chromatographic Column , 1987, The Journal of Geology.

[65]  D. McKenzie,et al.  Mantle reservoirs and ocean island basalts , 1983, Nature.

[66]  C. Dupuy,et al.  Origin of basalts from the Marquesas Archipelago (south central Pacific Ocean): isotope and trace element constraints , 1987 .

[67]  D. Green,et al.  The mineralogy, geochemistry and origin of Iherzolite inclusions in Victorian basanites , 1974 .

[68]  A. Saunders,et al.  Transverse geochemical variations across the Antarctic Peninsula: Implications for the genesis of calc-alkaline magmas , 1980 .

[69]  A. P. Roex,et al.  Geochemical correlation between southern African kimberlites and South Atlantic hotspots , 1986, Nature.

[70]  W. White,et al.  The petrology and geochemistry of the Azores Islands , 1979 .

[71]  I. Nakai,et al.  Kimuraite, CaY 2 (CO 3 ) 4 .6H 2 O, a new mineral from fissures in an alkali olivine basalt from Saga Prefecture, Japan, and new data on lokkaite , 1986 .

[72]  M. Tatsumoto.  Isotopic composition of lead in oceanic basalt and its implication to mantle evolution , 1978 .

[73]  C. Langmuir,et al.  The systematics of lithium abundances in young volcanic rocks , 1987 .

[74]  M. Gurnis,et al.  The effect of depth‐dependent viscosity on convective mixing in the mantle and the possible survival of primitive mantle , 1986 .

[75]  S. Taylor,et al.  Role of subducted sediments in island-arc magmatism: constraints from REE patterns , 1981 .

[76]  A. Hofmann,et al.  Ba, Rb and Cs in the Earth's Mantle , 1983 .

[77]  C. Langmuir,et al.  An evaluation of major element heterogeneity in the mantle sources of basalts , 1980, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[78]  J. Macdougall,et al.  Sr and Nd isotopes in basalts from the East Pacific Rise: significance for mantle heterogeneity , 1986 .

[79]  R. Finkel,et al.  Comparison of 230Th-238U disequilibrium systematics in lavas from three hot spot regions: Hawaii, Prince Edward and Samoa , 1984 .

[80]  Z. Palacz,et al.  Coupled trace element and isotope enrichment in the Cook-Austral-Samoa Islands, Southwest Pacific , 1986 .

[81]  T. Sekine,et al.  The formation of mantle phlogopite in subduction zone hybridization , 1982 .

[82]  R. Batiza,et al.  Isotope and trace element geochemistry of young Pacific seamounts: implications for the scale of upper mantle heterogeneity , 1984 .

[83]  D. Green.  Composition of Basaltic Magmas as Indicators of Conditions of Origin: Application to Oceanic Volcanism , 1971 .

[84]  A. Hofmann,et al.  Isotope geochemistry of Pacific Mid‐Ocean Ridge Basalt , 1987 .

[85]  C. Hawkesworth,et al.  143Nd/144Nd and 87Sr/86Sr ratios from the Azores and their significance in LIL-element enriched mantle , 1979, Nature.

[86]  S. H. Richardson,et al.  Origin of diamonds in old enriched mantle , 1984, Nature.

[87]  T. Bornhorst,et al.  Kahoolawe Island, Hawaii: Tholeiitic, alkalic, and unusual hydrothermal(?) “enrichment” characteristics , 1987 .

[88]  D. Clague,et al.  The isotope systematics of a juvenile intraplate volcano: Pb, Nd, and Sr isotope ratios of basalts from Loihi Seamount, Hawaii , 1984 .

[89]  G. Davies.  Earth's neodymium budget and structure and evolution of the mantle , 1981, Nature.

[90]  A. E. Ringwood,et al.  Phase Transformations and Differentiation in Subducted Lithosphere: Implications for Mantle Dynamics, Basalt Petrogenesis, and Crustal Evolution , 1982, The Journal of Geology.

[91]  C. Langmuir,et al.  Petrogenesis of basalts from the FAMOUS area: Mid-Atlantic Ridge , 1977 .

[92]  Y. Muramatsu,et al.  REE and selected trace elements in kimberlites from the Kimberley area (South Africa) , 1985 .

[93]  G. Hanson,et al.  Rare earth element evidence for differentiation of McMurdo volcanics, Ross Island, Antarctica , 1976 .

[94]  W. McDonough,et al.  Isotopic and geochemical systematics in Tertiary-Recent basalts from southeastern Australia and implications for the evolution of the sub-continental lithosphere , 1985 .

[95]  R. Armstrong.  A model for the evolution of strontium and lead isotopes in a dynamic Earth , 1968 .

[96]  A. Saunders,et al.  The geochemistry of basalts from a back-arc spreading centre in the East Scotia Sea , 1979 .

[97]  A. Chivas,et al.  Geochemical and isotopic systematics in carbonatites and implications for the evolution of ocean-island sources , 1988 .

[98]  Richard W. Carlson,et al.  Isotopic constraints on Columbia River flood basalt genesis and the nature of the subcontinental mantle , 1984 .

[99]  T. Green.  Rare earth geochemistry of basalts from Norfolk Island, and implications for mantle inhomogeneity in the rare earth elements , 1978 .

[100]  F. Richter.  Models for the Archean thermal regime , 1985 .

[101]  C. Hawkesworth,et al.  Sr, Nd and Pb isotope and minor element geochemistry of lamproites and kimberlites , 1985 .

[102]  D. James,et al.  Ancient lithosphere: its role in young continental volcanism. , 1976, Science.

[103]  A. E. Ringwood,et al.  Nature of the 650–km seismic discontinuity: implications for mantle dynamics and differentiation , 1988, Nature.

[104]  W. McDonough,et al.  The southeast Australian lithospheric mantle: isotopic and geochemical constraints on its growth and evolution , 1987 .

[105]  D. Green.  V. Petrogenesis and discussion , 1971, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[106]  Craig B. Smith.  Pb, Sr and Nd isotopic evidence for sources of southern African Cretaceous kimberlites , 1983, Nature.

[107]  C. Dupuy,et al.  Geochemistry and origin of basaltic lavas from Marquesas Archipelago, French Polynesia , 1986 .

[108]  S. Humphris,et al.  Hotspot—migrating ridge interaction in the South Atlantic , 1985, Nature.

[109]  S. Hart,et al.  A possible new Sr-Nd-Pb mantle array and consequences for mantle mixing , 1986 .

[110]  Shen-su Sun,et al.  Chemical heterogeneity of the Archaean mantle, composition of the earth and mantle evolution , 1977 .

[111]  K. G. Cox,et al.  Flood basalts, subduction and the break-up of Gondwanaland , 1978, Nature.

[112]  T. Jordan,et al.  Slab penetration into the lower mantle , 1984 .

[113]  G. Dreibus,et al.  THE ABUNDANCES OF MAJOR, MINOR, AND TRACE ELEMENTS IN THE EARTH'S MANTLE AS DERIVED FROM PRIMITIVE ULTRAMAFIC NODULES. , 1979 .

[114]  Albrecht W. Hofmann,et al.  Mantle plumes from ancient oceanic crust , 1982 .

[115]  G. Hanson,et al.  Origin of Ross Island basanitoids and limitations upon the heterogeneity of mantle sources for alkali basalts and nephelinites , 1975 .