Matches in SemOpenAlex for { <https://semopenalex.org/work/W4292265458> ?p ?o ?g. }
- W4292265458 endingPage "106839" @default.
- W4292265458 startingPage "106839" @default.
- W4292265458 abstract "The origin of carbonatitic and highly silica-undersaturated volcanism, common along the SW coast of Africa extending from Angola through Namibia to the tip of South Africa, is still poorly understood. Here we present new geochemical data (major and trace element and Sr-Nd-Pb-Hf-O-C isotopes) from the Agate Mountain calcio- to magnesio‑carbonatites (∼83 Ma), Dicker Willem calcio‑carbonatites (49 Ma) and Swakopmund basanitic plugs (76–72 Ma) along the coast of Namibia that were emplaced after the EMI (enriched mantle one) type Etendeka flood basalts. The trace element and isotopic composition of Agate Mountain carbonatites and Swakopmund basanites indicate that they were derived from a HIMU-type (high time-integrated 238 U/ 204 Pb with radiogenic Pb isotope ratios) magma source, similar to the St. Helena global HIMU endmember in the South Atlantic. The Agate Mountain carbonatites form part of the late-stage Walvis Ridge HIMU hotspot track overlying the EM1-type Walvis Ridge basement forming part of the Tristan-Gough hotspot track. The Dicker Willem carbonatites, however, extend to higher 206 Pb/ 204 Pb than St. Helena, but have similar 206 Pb/ 204 Pb to Mangaia HIMU lavas in the Pacific. Compared to Mangaia HIMU, the Dicker Willem carbonatites with mantle-type O and C isotopes have higher 207 Pb/ 204 Pb and 87 Sr/ 86 Sr but lower 143 Nd/ 144 Nd, suggesting it may represent a new HIMU endmember flavor. The HIMU carbonatitic and silica-undersaturated rocks form a belt of age-progressive volcanic tracks, including: 1) from the Walvis Ridge, through NW Namibia to central Angola, 2) from the Vema Seamount via Dicker Willem carbonatite to Gibeon kimberlites and carbonatites, 3) from the Namaqualand to Bushmanland and to Warmbad volcanic centers in northwestern South Africa, and 4) along the older end of the Shona EMI-type volcanic track extending into South Africa. Geochemical and seismic tomographic data suggest that the EMI and HIMU mantle plumes are generated from different geochemical domains at the base of the lower mantle. The Tristan-Gough, Discovery and Shona EM1 volcanic tracks are derived from a common low-velocity anomaly (superplume-like structure with three branching arms) ascending from the outer margin, possibly lower primoridal layer, of the African large low-shear-velocity province (LLSVP). Seismic low-velocity anomalies can be traced from beneath the belt of HIMU volcanism to an internal and shallower part of the LLSVP, located ∼900–1200 km east of the outer LLSVP margin and suggest that HIMU-type (possibly subducted oceanic lithospheric) material overlies EMI-type (possibly primordial) material in the internal part of the LLSVP. • A HIMU-like volcanism belt along the southwest Africa. • The HIMU-like volcanic complexes form age-progressive volcanic tracks. • EMI and HIMU mantle plumes are from different domains in the lower mantle." @default.
- W4292265458 created "2022-08-19" @default.
- W4292265458 creator A5011106285 @default.
- W4292265458 creator A5011152663 @default.
- W4292265458 creator A5011602679 @default.
- W4292265458 creator A5021053411 @default.
- W4292265458 creator A5023787845 @default.
- W4292265458 creator A5059392381 @default.
- W4292265458 creator A5062781095 @default.
- W4292265458 creator A5065881467 @default.
- W4292265458 date "2022-11-01" @default.
- W4292265458 modified "2023-10-18" @default.
- W4292265458 title "A HIMU volcanic belt along the SW African coast (∼83–49 Ma): New geochemical clues to deep mantle dynamics from carbonatite and silica-undersaturated complexes in Namibia" @default.
- W4292265458 cites W1520843566 @default.
- W4292265458 cites W1524759453 @default.
- W4292265458 cites W1914890451 @default.
- W4292265458 cites W1941456882 @default.
- W4292265458 cites W1948884945 @default.
- W4292265458 cites W1966917681 @default.
- W4292265458 cites W1971187422 @default.
- W4292265458 cites W1971788413 @default.
- W4292265458 cites W1972164452 @default.
- W4292265458 cites W1974107814 @default.
- W4292265458 cites W1974231715 @default.
- W4292265458 cites W1981040638 @default.
- W4292265458 cites W1982739504 @default.
- W4292265458 cites W1984194470 @default.
- W4292265458 cites W1987666342 @default.
- W4292265458 cites W1993449388 @default.
- W4292265458 cites W1997228875 @default.
- W4292265458 cites W2003271417 @default.
- W4292265458 cites W2005647481 @default.
- W4292265458 cites W2006298631 @default.
- W4292265458 cites W2006694921 @default.
- W4292265458 cites W2015154867 @default.
- W4292265458 cites W2021828598 @default.
- W4292265458 cites W2028642650 @default.
- W4292265458 cites W2035097203 @default.
- W4292265458 cites W2045743496 @default.
- W4292265458 cites W2051758022 @default.
- W4292265458 cites W2052001189 @default.
- W4292265458 cites W2065489771 @default.
- W4292265458 cites W2065629370 @default.
- W4292265458 cites W2070485494 @default.
- W4292265458 cites W2073281216 @default.
- W4292265458 cites W2077101751 @default.
- W4292265458 cites W2085876181 @default.
- W4292265458 cites W2089866577 @default.
- W4292265458 cites W2095657773 @default.
- W4292265458 cites W2098958698 @default.
- W4292265458 cites W2101179413 @default.
- W4292265458 cites W2105942108 @default.
- W4292265458 cites W2114299435 @default.
- W4292265458 cites W2119438235 @default.
- W4292265458 cites W2128847471 @default.
- W4292265458 cites W2137941714 @default.
- W4292265458 cites W2138522501 @default.
- W4292265458 cites W2143679365 @default.
- W4292265458 cites W2146433018 @default.
- W4292265458 cites W2158541765 @default.
- W4292265458 cites W2164369141 @default.
- W4292265458 cites W2167782460 @default.
- W4292265458 cites W2301288450 @default.
- W4292265458 cites W2309906489 @default.
- W4292265458 cites W2318507711 @default.
- W4292265458 cites W2555702031 @default.
- W4292265458 cites W2571129369 @default.
- W4292265458 cites W2753462303 @default.
- W4292265458 cites W2757290645 @default.
- W4292265458 cites W2800351724 @default.
- W4292265458 cites W2800604401 @default.
- W4292265458 cites W2801998446 @default.
- W4292265458 cites W2884420006 @default.
- W4292265458 cites W2890143845 @default.
- W4292265458 cites W2945221819 @default.
- W4292265458 cites W2963773632 @default.
- W4292265458 cites W3005428716 @default.
- W4292265458 cites W3042375443 @default.
- W4292265458 cites W3111592415 @default.
- W4292265458 cites W4225124539 @default.
- W4292265458 cites W978601029 @default.
- W4292265458 doi "https://doi.org/10.1016/j.lithos.2022.106839" @default.
- W4292265458 hasPublicationYear "2022" @default.
- W4292265458 type Work @default.
- W4292265458 citedByCount "2" @default.
- W4292265458 countsByYear W42922654582023 @default.
- W4292265458 crossrefType "journal-article" @default.
- W4292265458 hasAuthorship W4292265458A5011106285 @default.
- W4292265458 hasAuthorship W4292265458A5011152663 @default.
- W4292265458 hasAuthorship W4292265458A5011602679 @default.
- W4292265458 hasAuthorship W4292265458A5021053411 @default.
- W4292265458 hasAuthorship W4292265458A5023787845 @default.
- W4292265458 hasAuthorship W4292265458A5059392381 @default.
- W4292265458 hasAuthorship W4292265458A5062781095 @default.
- W4292265458 hasAuthorship W4292265458A5065881467 @default.
- W4292265458 hasConcept C120806208 @default.
- W4292265458 hasConcept C127313418 @default.
- W4292265458 hasConcept C140441402 @default.