Publication Date:
2023-06-27
Description:
The compositions of abyssal glasses obtained on Leg 82 of the awGlomar Challenger and the MAPCO cruise of Jean Charcot have been investigated. Two main compositional groups of Atlantic glasses (A1 and A2) that are separated in space and time were identified. The distribution of these groups in the studied area allowed mapping of the transition zone from A1 to A2 between 30-35°N MAR. We infer that the compositional groups of abyssal glasses of the Atlantic and other oceans reflect the depth of separation of primary melts from the oceanic mantle. Specifically, the primary melt of Group A1 separates from the mantle at a depth of 30-60 km (spinel-peridotite facies) and those for Group A2 from a depth of 15-30 km (plagioclase-peridotite facies). Modifications of dynamic models of the ocean lithosphere are discussed.
Keywords:
82-556; 82-558; 82-559; 82-561; 82-562; 82-563; 82-564; AGE; Age, maximum/old; Age, minimum/young; Aluminium oxide; Aluminium oxide, standard deviation; Calcium oxide; Calcium oxide, standard deviation; Calculated, see reference(s); CH97-DR02; CH98-DR07; CH98-DR08; CH98-DR09; CH98-DR11; CH98-DR12; CH98-DR14; CH98-DR15; Deep Sea Drilling Project; Description; Dredge; DRG; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Electron microprobe (EMP); Elevation of event; Event label; Glomar Challenger; Iron oxide, FeO; Iron oxide, FeO, standard deviation; Jean Charcot; Latitude of event; Leg82; Longitude of event; Magnesium oxide; Magnesium oxide, standard deviation; Mapco-ch97; Mapco-ch98; Mid-Atlantic Ridge; North Atlantic; North Atlantic/RIDGE; Parameter; Piece; Potassium oxide; Potassium oxide, standard deviation; Replicates; Sample, optional label/labor no; Sample code/label; Silicon dioxide; Silicon dioxide, standard deviation; Sodium oxide; Sodium oxide, standard deviation; Standard deviation; Titanium dioxide; Titanium dioxide, standard deviation; Total
Type:
Dataset
Format:
text/tab-separated-values, 567 data points
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