Lithospheric mantle

Williams RW, Collerson KD, Gill JB, Deniel C (1992) High Th/U ratios in subcontinental lithospheric mantle mass spectrometric measurement of Th isotopes in Gaussberg lamproites. Eartli Planet Sci Lett 111 257-268... 

Asmeron Y, Cheng H, Thomas R, Hirschmann M, Edwards RL (2000) Melting of the Earth s lithospheric mantle inferred from protactiiuum-thorium-uianium isotopic data. Nature 406 293-296... 

At shallow pressure (less than 1 GPa), Th becomes slightly more compatible than U in clinopyroxene (Landwehr et al. 2001) and garnet is not stable even in pyroxenite or eclogite. On the other hand, it is believed (mostly based on observations) that Pa remains more incompatible than U through the entire length of the melt column. Thus, melting at intermediate pressure should yield small °Th or U excesses, but significant Pa excess. This has been observed in the lithospheric mantle in the Colorado plateau by... 

Regionally, three magmatic processes are envisioned to have ultimately controlled mineralization at Morila 1) re-melting of metasomatized lithospheric mantle during crustal-scale regional transpression 2)... 

Sources of information about the isotopic composition of the upper portion of the lithospheric mantle come from the direct analysis of unaltered ultramafic xenoliths brought rapidly to the surface in explosive volcanic vents. Due to rapid transport, these peridotite nodules are in many cases chemically fresh and considered by most... 

Although the results of Mattey et al. (1994) have been confirmed by Chazot et al. (1997), it should be kept in mind that most of the mantle peridotites that have been analyzed for 5 0 originate from the continental lithospheric mantle and not from the mantle as a whole. More recently, there have been several indications that... 

Boyd SR, PUlinger CT, Mflledge HJ, Mendelssohn MJ, Seal M (1992) C and N isotopic composition and the infrared absorption spectra of coated diamonds evidence for the regional uniformity of CO2-H2O rich fluids in lithospheric mantle. Earth Planet Sci Lett 109 633-644... 

Beccaluva L, Bianchini G, Coltorti M, Perkins WT, Siena F, Vaccaro C, Wilson M (2001) Multistage evolution of the European lithospheric mantle new evidence from Sardinian peridotite xenoliths. Contrib Mineral Petrol 142 284-297... 

Downes H (2001) Formation and modification of the shallow sub-continental lithospheric mantle a review of geochemical evidence from ultramafic xenolith suites and tectonically emplaced ultramafic massifs of Western and Central Europe. J Petrol 42 233-250... 

Lustrino M, Melluso L, Morra V, Secchi F (1996) Petrology of Plio-Quatemary volcanic rocks from central Sardinia. Per Mineral 65 275-287 Lustrino M, Melluso L, Morra V (2000) The role of lower continental crust and lithospheric mantle in the genesis of Plio-Pleistocene volcanic rocks from Sardinia (Italy). Earth Planet Sci Lett 180 259-270 Lustrino M, Melluso L, Morra V (2002) The transition from alkaline to tholeiitic magmas a case study from the Orosei-Dorgali Pliocene volcanic district (NE Sardinia, Italy). Lithos 63 83-113... 

Matsumoto, T., Honda, M., McDougall, I., Yatsevich, I., O Reilly, S. Y. (1997) Plume-like neon in a metasomatic apatite from the Australian lithospheric mantle. Nature, 388, 162-4. 

Jochum K. P., McDonough W. F., Pahne H., and Spettel B. (1989) Compositional constraints on the continental lithospheric mantle from trace elements in spinel peridotite xenoliths. Nature 340, 548-550. 

McDonough W. F. (1990) Constraints on the composition of the continental lithospheric mantle. Earth Planet. Sci. Lett. 101, 1-18. 

Alard O., Griffin W. L., Pearson N. J., Lorand J. P., and O Reilly S. Y. (2002) New insights into the Re-Os systematics of sub-continental lithospheric mantle from in situ analysis of sulphides. Earth Planet. Set Lett. 203(2), 651-663. 

To explain the denudation of peridotites on the seafloor before the onset of oceanic accretion, Lemoine et al. (1987) and Trommsdorff et al. (1993) proposed a model involving extensional exhumation of subcontinental mantle along a major, normal detachment fault rooted in the crust-mantle boundary (Wernicke, 1981,1985). In most cases, however, the peridotites record a higher-temperature evolution than would be expected from stable lithospheric mantle. This suggests that ... 

An alternative to this scenario is to envisage that some fertile orogenic Iherzolites have acquired their geochemical signature as a result of melting and melt-rock interaction processes associated with the thermomechanical erosion of lithospheric mantle by upweUing asthenosphere (e.g., Lenoir et al., 2001). In this scheme, refertilization of lithospheric peridotites by (and reequilibration with) MORB melts is an alternative to the small degrees of melt extraction to account for LREE depletion in otherwise fertile Iherzolites (e.g., Piccardo and Rampone, 2001). 

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