Matches in SemOpenAlex for { <https://semopenalex.org/work/W2328307511> ?p ?o ?g. }
- W2328307511 abstract "Abstract The geochemical structure of the upper mantle in general and its noble gas isotopic structure in particular have been the subject of countless studies, as both provide important insights into mantle dynamic processes and are essential for the formulation of mantle geodynamic models. This contribution presents a noble gas study of basaltic glasses derived from the Mid-Atlantic Ridge (MAR) between 4° and 12°S, an area well known for its high degree of lithophile isotope heterogeneity and its anomalous crustal thickness. The Sr, Nd, Pb and Hf isotopic systematics along this segment of the MAR range from strongly depleted (i.e. more depleted than N-MORB) to highly enriched. Different concepts have been proposed to explain the observed isotopic signatures. Here we show that the high degree of heterogeneity is not confined to the isotopes of the lithophile elements, but is also shown by the noble gas isotopes and noble gas interelement ratios, such as 3He/22NeM or 4He/40Ar∗. Helium isotopic ratios (3He/4He), 21Ne/22Neextra and 40Ar/36Ar range from 7.34 ± 0.06 to 9.38 ± 0.08 RA, from 0.039 ± 0.020 to 0.075 ± 0.007, and from 346 ± 5 to 37,400 ± 1300, respectively. However, the majority of the Ne isotope data are clearly aligned along a single mixing line in the Ne three-isotope diagram, represented by the equation 20Ne/22Ne = 70.5 × 21Ne/22Ne + 7.782, with a slope distinctly less than that of the MORB line. This indicates that the strongly depleted material is characterised by a significantly more nucleogenic Ne isotopic composition than the normal depleted mantle. We show, based on covariations between 3He/4He and 21Ne/22Neextra with 206Pb/204Pb and 178Hf/177Hf that the strongly depleted material erupted at this MAR segment was most likely produced by an ancient melting event. This implies that isotopic heterogeneities in the upper mantle are not solely caused by the injection of enriched materials from deep-seated mantle plumes or by crustal recycling but may also be due to differences in the depth and degree of melting of upper mantle material over the lifetime of our planet. In addition, the observed along-ridge and off-axis isotope patterns in conjunction with spatial distribution patterns of off-axis seamounts in the area show that the upper mantle can be extremely heterogeneous in space and time even at small scales. This implies that the mixing efficiency of either large- or small-scale convection processes in the upper mantle might be lower than assumed." @default.
- W2328307511 created "2016-06-24" @default.
- W2328307511 creator A5033082636 @default.
- W2328307511 creator A5040585074 @default.
- W2328307511 date "2016-06-01" @default.
- W2328307511 modified "2023-09-27" @default.
- W2328307511 title "He, Ne and Ar isotope signatures of mid-ocean ridge basalts and their implications for upper mantle structure: A case study from the Mid-Atlantic Ridge at 4–12°S" @default.
- W2328307511 cites W1494042572 @default.
- W2328307511 cites W1534749586 @default.
- W2328307511 cites W1565650889 @default.
- W2328307511 cites W1585384165 @default.
- W2328307511 cites W1652864201 @default.
- W2328307511 cites W1669472802 @default.
- W2328307511 cites W1680017751 @default.
- W2328307511 cites W1838719551 @default.
- W2328307511 cites W1965648866 @default.
- W2328307511 cites W1968103406 @default.
- W2328307511 cites W1969051912 @default.
- W2328307511 cites W1969933946 @default.
- W2328307511 cites W1971453987 @default.
- W2328307511 cites W1974731988 @default.
- W2328307511 cites W1977893035 @default.
- W2328307511 cites W1979496533 @default.
- W2328307511 cites W1982978456 @default.
- W2328307511 cites W1985501963 @default.
- W2328307511 cites W1986739254 @default.
- W2328307511 cites W1990832360 @default.
- W2328307511 cites W1991976121 @default.
- W2328307511 cites W1993432699 @default.
- W2328307511 cites W1995857854 @default.
- W2328307511 cites W2002278475 @default.
- W2328307511 cites W2008489622 @default.
- W2328307511 cites W2011361221 @default.
- W2328307511 cites W2011580798 @default.
- W2328307511 cites W2011607179 @default.
- W2328307511 cites W2017295737 @default.
- W2328307511 cites W2020467041 @default.
- W2328307511 cites W2027926045 @default.
- W2328307511 cites W2027961528 @default.
- W2328307511 cites W2030364506 @default.
- W2328307511 cites W2030936724 @default.
- W2328307511 cites W2033819548 @default.
- W2328307511 cites W2037419921 @default.
- W2328307511 cites W2040277509 @default.
- W2328307511 cites W2041348481 @default.
- W2328307511 cites W2042026694 @default.
- W2328307511 cites W2045351375 @default.
- W2328307511 cites W2047125575 @default.
- W2328307511 cites W2047567126 @default.
- W2328307511 cites W2056233822 @default.
- W2328307511 cites W2065489771 @default.
- W2328307511 cites W2068063302 @default.
- W2328307511 cites W2088201423 @default.
- W2328307511 cites W2088541838 @default.
- W2328307511 cites W2091919465 @default.
- W2328307511 cites W2095203624 @default.
- W2328307511 cites W2098490586 @default.
- W2328307511 cites W2098839042 @default.
- W2328307511 cites W2105607777 @default.
- W2328307511 cites W2105885462 @default.
- W2328307511 cites W2112882114 @default.
- W2328307511 cites W2139296091 @default.
- W2328307511 cites W2150498084 @default.
- W2328307511 cites W2171611994 @default.
- W2328307511 cites W2234747848 @default.
- W2328307511 cites W2334605641 @default.
- W2328307511 cites W2340622928 @default.
- W2328307511 cites W2883478268 @default.
- W2328307511 doi "https://doi.org/10.1016/j.gca.2016.04.002" @default.
- W2328307511 hasPublicationYear "2016" @default.
- W2328307511 type Work @default.
- W2328307511 sameAs 2328307511 @default.
- W2328307511 citedByCount "5" @default.
- W2328307511 countsByYear W23283075112016 @default.
- W2328307511 countsByYear W23283075112018 @default.
- W2328307511 countsByYear W23283075112021 @default.
- W2328307511 crossrefType "journal-article" @default.
- W2328307511 hasAuthorship W2328307511A5033082636 @default.
- W2328307511 hasAuthorship W2328307511A5040585074 @default.
- W2328307511 hasConcept C121332964 @default.
- W2328307511 hasConcept C121530826 @default.
- W2328307511 hasConcept C127313418 @default.
- W2328307511 hasConcept C129956564 @default.
- W2328307511 hasConcept C146458902 @default.
- W2328307511 hasConcept C151730666 @default.
- W2328307511 hasConcept C161509811 @default.
- W2328307511 hasConcept C164304813 @default.
- W2328307511 hasConcept C17409809 @default.
- W2328307511 hasConcept C184779094 @default.
- W2328307511 hasConcept C20443986 @default.
- W2328307511 hasConcept C2778044477 @default.
- W2328307511 hasConcept C2779377894 @default.
- W2328307511 hasConcept C32277403 @default.
- W2328307511 hasConcept C62520636 @default.
- W2328307511 hasConcept C67236022 @default.
- W2328307511 hasConcept C79572550 @default.
- W2328307511 hasConceptScore W2328307511C121332964 @default.
- W2328307511 hasConceptScore W2328307511C121530826 @default.
- W2328307511 hasConceptScore W2328307511C127313418 @default.
- W2328307511 hasConceptScore W2328307511C129956564 @default.