An occurrence of igneous orthorhombic amphibole, Eriksberg gabbro, southern Sweden
-
Dick T. Claeson
and
William P. Meurer
Abstract
We document the first reported igneous occurrence of the orthoamphibole, gedrite, from a troctolitic cumulate in the Eriksberg gabbro, Sweden. The gedrite is sodic and coexists in textural equilibrium with plagioclase, orthopyroxene, Ca-amphibole, and Na-rich phlogopite. The gedrite crystallized from evolved interstitial liquid that was buffered by cumulus olivine. Geothermometry indicates that the assemblage equilibrated at around 900 °C and 4-6 kbar. Gedrite shows a convex- downward REE-profile, with a positive Eu anomaly. The rare earth element concentrations are ~0.2 to 0.8 times chondritic abundances and much lower than in coexisting Ca-amphibole. Laser ablation ICP-MS analyses show that the gedrite has much lower concentrations of Zr, Nb, Th, and U, and lower concentrations of Sr, Ba, Rb, and Pb relative to co-crystallizing Ca-amphibole. However, nickel and cobalt partition preferentially into gedrite. Comparison of Zr and Nb concentrations in early crystallized Ca-amphibole with gedrite and associated Ca-amphibole reveals that Xmg of amphibole is not the best criteria to use for estimates of (DAmpf/LNb/Zr ) for cumulates where olivine is buffering the Mg/(Mg + Fe).
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Formation of secondary pyrite and carbonate minerals in the Lower Williams Lake tailings basin, Elliot Lake, Ontario, Canada
- Hydroxyl in MgSiO3 akimotoite: A polarized and high-pressure IR study
- High-pressure IR-spectra and the thermodynamic properties of chloritoid
- Infrared and Raman study of interlayer anions CO32–, NO3–, SO42– and ClO4– in Mg/Al-hydrotalcite
- Effect of Fe oxidation state on the IR spectra of Garfield nontronite
- High-pressure single-crystal X-ray diffraction study of katoite hydrogarnet: Evidence for a phase transition from Ia3d →I4̅3d symmetry at 5 GPa
- The high-temperature P21/c-C2/c phase transition in Fe-free pyroxene (Ca0.15Mg1.85Si2O6): Structural and thermodynamic behavior
- Thermodynamics and stability of pseudobrookite-type MgTi2O5 (karrooite)
- Molecular orbital calculations on aluminosilicate tricluster molecules: Implications for the structure of aluminosilicate glasses
- Surface structures, stabilities, and growth of magnesian calcites: A computational investigation from the perspective of dolomite formation
- Spinels and other oxides in Mn-rich rocks from the Hutter Mine, Pittsylvania County, Virginia, U.S.A.: Implications for miscibility and solvus relations among jacobsite, galaxite, and magnetite
- An occurrence of igneous orthorhombic amphibole, Eriksberg gabbro, southern Sweden
- Crystal chemistry of Cr3+-V3+-rich clinopyroxenes
- The crystal structures of cesanite and its synthetic analogue—A comparison
- Disordered distribution of Cu in the crystal structure of leightonite, K2Ca2Cu(SO4)4 · 2H2O
- Neustädtelite and cobaltneustädtelite, the Fe3+ - and Co2+ -analogues of medenbachite
- Ciprianiite and mottanaite-(Ce), two new minerals of the hellandite group from Latium (Italy)
- Re-definition, nomenclature and crystal-chemistry of the hellandite group
- The new mineral baumstarkite and a structural reinvestigation of aramayoite and miargyrite
- Letters. Isotopic and elemental partitioning of boron between hydrous fluid and silicate melt
- Experimental evidence of three coexisting immiscible fluids in synthetic granitic pegmatite
- Quantifying surface areas of clays by atomic force microscopy
- A new high-pressure phase of FeSi
Articles in the same Issue
- Formation of secondary pyrite and carbonate minerals in the Lower Williams Lake tailings basin, Elliot Lake, Ontario, Canada
- Hydroxyl in MgSiO3 akimotoite: A polarized and high-pressure IR study
- High-pressure IR-spectra and the thermodynamic properties of chloritoid
- Infrared and Raman study of interlayer anions CO32–, NO3–, SO42– and ClO4– in Mg/Al-hydrotalcite
- Effect of Fe oxidation state on the IR spectra of Garfield nontronite
- High-pressure single-crystal X-ray diffraction study of katoite hydrogarnet: Evidence for a phase transition from Ia3d →I4̅3d symmetry at 5 GPa
- The high-temperature P21/c-C2/c phase transition in Fe-free pyroxene (Ca0.15Mg1.85Si2O6): Structural and thermodynamic behavior
- Thermodynamics and stability of pseudobrookite-type MgTi2O5 (karrooite)
- Molecular orbital calculations on aluminosilicate tricluster molecules: Implications for the structure of aluminosilicate glasses
- Surface structures, stabilities, and growth of magnesian calcites: A computational investigation from the perspective of dolomite formation
- Spinels and other oxides in Mn-rich rocks from the Hutter Mine, Pittsylvania County, Virginia, U.S.A.: Implications for miscibility and solvus relations among jacobsite, galaxite, and magnetite
- An occurrence of igneous orthorhombic amphibole, Eriksberg gabbro, southern Sweden
- Crystal chemistry of Cr3+-V3+-rich clinopyroxenes
- The crystal structures of cesanite and its synthetic analogue—A comparison
- Disordered distribution of Cu in the crystal structure of leightonite, K2Ca2Cu(SO4)4 · 2H2O
- Neustädtelite and cobaltneustädtelite, the Fe3+ - and Co2+ -analogues of medenbachite
- Ciprianiite and mottanaite-(Ce), two new minerals of the hellandite group from Latium (Italy)
- Re-definition, nomenclature and crystal-chemistry of the hellandite group
- The new mineral baumstarkite and a structural reinvestigation of aramayoite and miargyrite
- Letters. Isotopic and elemental partitioning of boron between hydrous fluid and silicate melt
- Experimental evidence of three coexisting immiscible fluids in synthetic granitic pegmatite
- Quantifying surface areas of clays by atomic force microscopy
- A new high-pressure phase of FeSi
