10.1594/PANGAEA.711293
Coogan, Laurence A
Laurence A
Coogan
Kempton, Pamela D
Pamela D
Kempton
Saunders, Andrew D
Andrew D
Saunders
Norry, Michael J
Michael J
Norry
Element concentrations of plagioclase and clinopyroxene in poikilitic olivine gabbros from ODP Hole 153-923A (Table 4)
PANGAEA
2000
ORDINAL NUMBER
Sample code/label
Plagioclase
Clinopyroxene
Olivine
Sample comment
Minerals
Comment
Silicon dioxide
Titanium dioxide
Aluminium oxide
Chromium(III) oxide
Iron oxide, FeO
Manganese oxide
Magnesium oxide
Calcium oxide
Sodium oxide
Calcium/(Calcium+Sodium+Potassium) ratio
Magnesium number
Titanium
Strontium
Yttrium
Zirconium
Lanthanum
Cerium
Praseodymium
Neodymium
Samarium
Europium
Gadolinium
Terbium
Dysprosium
Holmium
Erbium
Ytterbium
Drilling/drill rig
DSDP/ODP/IODP sample designation
Electron Probe Microanalysis (EPMA)
Calculated
Ion probe analysis
Leg153
Joides Resolution
Ocean Drilling Program (ODP)
1994-01-07T17:27:00/1994-01-13T02:45:00
en
Supplementary Dataset
10.1016/S0012-821X(00)00006-6
401 data points
text/tab-separated-values
Creative Commons Attribution 3.0 Unported
Ocean Drilling Program Hole 923A, located on the western flank of the Mid-Atlantic Ridge south of the Kane Fracture Zone, recovered primitive gabbros that have mineral trace element compositions inconsistent with growth from a single parental melt. Plagioclase crystals commonly show embayed anorthitic cores overgrown by more albitic rims. Ion probe analyses of plagioclase cores and rims show consistent differences in trace element ratios, indicating variation in the trace element characteristics of their respective parental melts. This requires the existence of at least two distinct melt compositions within the crust during the generation of these gabbros. Melt compositions calculated to be parental to plagioclase cores are depleted in light rare earth elements, but enriched in yttrium, compared to basalts from this region of the Mid-Atlantic Ridge, which are normal mid-ocean ridge basalt (N-MORB). Clinopyroxene trace element compositions are similar to those predicted to be in equilibrium with N-MORB. However, primitive clinopyroxene crystals are much more magnesian than those produced in one-atmosphere experiments on N-MORB, suggesting that the major element composition of the melt was unlike N-MORB. These data require that the diverse array of melt compositions generated within the mantle beneath mid-ocean ridges are not always fully homogenised during melt extraction from the mantle and that the final stage of mixing can occur efficiently within crustal magma chambers. This has implications for the process of melt extraction from the mantle and the liquid line of descent of MORB
Supplement to: Coogan, Laurence A; Kempton, Pamela D; Saunders, Andrew D; Norry, Michael J (2000): Melt aggregation within the crust beneath the Mid-Atlantic Ridge: evidence from plagioclase and clinopyroxene major and trace element compositions. Earth and Planetary Science Letters, 176(2), 245-257
-45.0316
23.5426
South Atlantic Ocean