Restite-melt and mafic–felsic magma mixing and mingling in an S-type dacite, Cerro del Hoyazo, southeastern Spain

1992 ◽  
pp. 139-144
Author(s):  
H. P. Zeck
Keyword(s):  
Magma Mixing ◽  
Felsic Magma ◽  
Southeastern Spain ◽  
Magma Mixing And Mingling

Restite-melt and mafic-felsic magma mixing and mingling in an S-type dacite, Cerro del Hoyazo, southeastern Spain

1992 ◽  
Vol 83 (1-2) ◽  
pp. 139-144 ◽  
Author(s):  
H. P. Zeck
Keyword(s):  
Magma Mixing ◽  
Mafic Magma ◽  
Felsic Magma ◽  
Pelitic Rock ◽  
Rock Fragments ◽  
Southeastern Spain ◽  
Magma Mixing And Mingling ◽  
Glass Base

ABSTRACTApproximately 10-15 vol% of the Neogene Hoyazo dacite consists of Al-rich restite rock inclusions (A12O3 = 20–45%) and monocrystal inclusions derived therefrom. Restite material and dacitic melt were formed syngenetically from a (semi-)pelitic rock sequence by means of anatexis. Restite rock fragments and dacite show similar high δ18O values (13–16‰) corresponding to those found for sedimentary material. Striking monocrystal restite inclusions in the dacite rock are graphite crystals measuring a few hundred μm, 0.5–10 mm blue cordierite crystals and 2–10 mm ruby red crystals of almandine-rich garnet (1.1 ± 0.2 vol%). Although the almandine crystals are perfectly euhedral, they are identical in every respect to the crystals found in the Al-rich restite rock inclusions and cannot be crystallisation products of the magmatic melt. The dacite also contains many inclusions of quartz gabbroic and basaltoid material which contains inclusions identical to the restite material found in the dacitic glass base. Many basaltoid inclusions show well-developed chilled borders. These inclusions may represent a more mafic magma of deeper origin which mixed with some dacite magma before mingling into it.

Geochemical composition, petrography and 40Ar/39Ar age of the Heldburg phonolite: implications on magma mixing and mingling

2015 ◽  
Vol 104 (8) ◽  
pp. 2033-2055 ◽  
Author(s):  
Michael Abratis ◽  
Lothar Viereck ◽  
Jörg A. Pfänder ◽  
Roland Hentschel
Keyword(s):  
Magma Mixing ◽  
Geochemical Composition ◽  
Magma Mixing And Mingling
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