Matches in SemOpenAlex for { <https://semopenalex.org/work/W2116770117> ?p ?o ?g. }
- W2116770117 endingPage "602" @default.
- W2116770117 startingPage "565" @default.
- W2116770117 abstract "The discovery of chemically and isotopically enriched mid-ocean ridge basalts (E-MORB) has offered substantial insight into the origin, time scales, and length scales of mantle heterogeneity. However, the exact processes involved in producing this E-MORB enrichment are vigorously debated. Additionally, because the ages of E-MORB are not well constrained, the petrogenetic, temporal, and geological relationships between E-MORB and normal (N)-MORB are not known. To investigate these relationships and to explore how melting and melt transport processes contribute to or modify enriched mantle source compositions and generate E-MORB melts beneath mid-ocean ridges, we measured major and trace elements, and Sr, Nd, Hf, Pb, and U–Th–Ra isotopes for a suite of lavas that were collected off-axis, including several E-MORB, at 9–10°N along the East Pacific Rise (EPR). These data show coherent mixing trends among long-lived radiogenic isotopes, U-series nuclides, and incompatible trace elements, implying that mixing of melts from different sources occurs at different depths. Our results are consistent with previous studies that show that melting occurs in a two-porosity melting regime, with high-porosity channels forming deeply in the presence of garnet and transporting enriched melts with large 230Th excesses to the crust, whereas low-porosity channels transport melts more slowly, allowing them to equilibrate at shallow depths and develop large 226Ra excesses at the expense of diminished 230Th excesses. Forward modeling of the trace element data also is consistent with mixing of melts in a two-porosity melting regime. U-series age constraints suggest that E-MORB neither erupt at systematically different times from N-MORB, nor necessarily through different pathways. Previous studies of E-MORB at 9–10°N have suggested that E-MORB compositions could be explained by off-axis eruption. However, when considered in light of previously published magnetic paleointensity and U-series age constraints, recent geological studies, and the most widely accepted contemporary understanding of volcanic construction at 9–10°N EPR, the asymmetric, off-axis distribution of E-MORB at 9–10°N EPR is consistent with, and more simply explained by, a model in which E-MORB erupted within the axial summit trough (AST) and flowed down the ridge flanks (∼0–3 km). These E-MORB subsequently spread away from the AST, and, finally, were preserved on the seafloor through asymmetric construction of the extrusive layer. Taken together, the range of ages of E-MORB at 9–10°N EPR and the geochemical and isotopic mixing trends suggest that enriched melts are continuously supplied to the ridge axis, but because of their small proportions relative to the volumetrically and volcanically dominant N-MORB, E-MORB preservation and exposure is comparatively scarce." @default.
- W2116770117 created "2016-06-24" @default.
- W2116770117 creator A5068004091 @default.
- W2116770117 creator A5072608267 @default.
- W2116770117 creator A5075189526 @default.
- W2116770117 creator A5084979688 @default.
- W2116770117 creator A5088178848 @default.
- W2116770117 date "2011-02-01" @default.
- W2116770117 modified "2023-09-26" @default.
- W2116770117 title "Perspective on the Genesis of E-MORB from Chemical and Isotopic Heterogeneity at 9–10°N East Pacific Rise" @default.
- W2116770117 cites W1492320237 @default.
- W2116770117 cites W1498894439 @default.
- W2116770117 cites W1531523923 @default.
- W2116770117 cites W1539311582 @default.
- W2116770117 cites W1540907122 @default.
- W2116770117 cites W1563674614 @default.
- W2116770117 cites W1564196663 @default.
- W2116770117 cites W1583276569 @default.
- W2116770117 cites W1599895293 @default.
- W2116770117 cites W1618885316 @default.
- W2116770117 cites W1653650875 @default.
- W2116770117 cites W1688191693 @default.
- W2116770117 cites W1825776342 @default.
- W2116770117 cites W1834626904 @default.
- W2116770117 cites W1963123502 @default.
- W2116770117 cites W1966673879 @default.
- W2116770117 cites W1968952222 @default.
- W2116770117 cites W1969393701 @default.
- W2116770117 cites W1969859799 @default.
- W2116770117 cites W1972575196 @default.
- W2116770117 cites W1973845726 @default.
- W2116770117 cites W1974927624 @default.
- W2116770117 cites W1976172463 @default.
- W2116770117 cites W1976766977 @default.
- W2116770117 cites W1983397141 @default.
- W2116770117 cites W1984243798 @default.
- W2116770117 cites W1987180374 @default.
- W2116770117 cites W1987734384 @default.
- W2116770117 cites W1987801494 @default.
- W2116770117 cites W1988974035 @default.
- W2116770117 cites W1989985088 @default.
- W2116770117 cites W1990814837 @default.
- W2116770117 cites W1991446948 @default.
- W2116770117 cites W1993409945 @default.
- W2116770117 cites W1993449388 @default.
- W2116770117 cites W1997268075 @default.
- W2116770117 cites W1997932126 @default.
- W2116770117 cites W1998619676 @default.
- W2116770117 cites W2000181793 @default.
- W2116770117 cites W2002041994 @default.
- W2116770117 cites W2002128134 @default.
- W2116770117 cites W2002519961 @default.
- W2116770117 cites W2003948785 @default.
- W2116770117 cites W2005124268 @default.
- W2116770117 cites W2005864914 @default.
- W2116770117 cites W2007112195 @default.
- W2116770117 cites W2011494202 @default.
- W2116770117 cites W2011607179 @default.
- W2116770117 cites W2012738669 @default.
- W2116770117 cites W2012864958 @default.
- W2116770117 cites W2018299106 @default.
- W2116770117 cites W2019884843 @default.
- W2116770117 cites W2022086679 @default.
- W2116770117 cites W2023398449 @default.
- W2116770117 cites W2023419609 @default.
- W2116770117 cites W2025061891 @default.
- W2116770117 cites W2027239029 @default.
- W2116770117 cites W2029142498 @default.
- W2116770117 cites W2029688186 @default.
- W2116770117 cites W2029944417 @default.
- W2116770117 cites W2030992170 @default.
- W2116770117 cites W2033676337 @default.
- W2116770117 cites W2033774424 @default.
- W2116770117 cites W2034388111 @default.
- W2116770117 cites W2035743760 @default.
- W2116770117 cites W2036709432 @default.
- W2116770117 cites W2041145438 @default.
- W2116770117 cites W2041169676 @default.
- W2116770117 cites W2042423268 @default.
- W2116770117 cites W2042768776 @default.
- W2116770117 cites W2048112478 @default.
- W2116770117 cites W2048457570 @default.
- W2116770117 cites W2048666919 @default.
- W2116770117 cites W2049250499 @default.
- W2116770117 cites W2050141585 @default.
- W2116770117 cites W2050480893 @default.
- W2116770117 cites W2055397105 @default.
- W2116770117 cites W2060921520 @default.
- W2116770117 cites W2063315641 @default.
- W2116770117 cites W2064822299 @default.
- W2116770117 cites W2066968098 @default.
- W2116770117 cites W2073082793 @default.
- W2116770117 cites W2073426602 @default.
- W2116770117 cites W2073730823 @default.
- W2116770117 cites W2078398291 @default.
- W2116770117 cites W2083828239 @default.
- W2116770117 cites W2084710809 @default.
- W2116770117 cites W2086206043 @default.