Skip to Main Content
Book Chapter

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

By
H. P. Zeck
H. P. Zeck
Search for other works by this author on:
Published:
January 01, 1992

Approximately 10–15 vol% of the Neogene Hoyazo dacite consists of Al-rich restite rock inclusions (Al2O3= 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.

You do not currently have access to this article.

Figures & Tables

Contents

GSA Special Papers

The Second Hutton Symposium on the Origin of Granites and Related Rocks

P. E. Brown
P. E. Brown
Search for other works by this author on:
B. W. Chappell
B. W. Chappell
Search for other works by this author on:
Geological Society of America
Volume
272
ISBN print:
9780813722726
Publication date:
January 01, 1992

References

Related

Citing Books via

A comprehensive resource of eBooks for researchers in the Earth Sciences

Related Articles
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal