Publication Date:
2022-05-25
Description:
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nguyen, D. K., Morishita, T., Soda, Y., Tamura, A., Ghosh, B., Harigane, Y., France, L., Liu, C., Natland, J. H., Sanfilippo, A., MacLeod, C. J., Blum, P., & Dick, H. J. B. (2018). Occurrence of felsic rocks in oceanic gabbros from IODP hole U1473A: Implications for evolved melt migration in the lower oceanic crust. Minerals, 8(12), 583, doi:10.3390/min8120583.
Description:
Felsic rocks are minor in abundance but occur ubiquitously in International Ocean Discovery Program Hole U1473A, Southwest Indian Ridge. The trace element abundances of high-Ti brown amphibole, plagioclase, and zircon in veins, as well as the presence of myrmekitic texture in the studied felsic rocks support crystallization origin from highly-evolved melts, probably controlled by fractional crystallization. Based on geochemical criteria and texture of the mineral assemblage in felsic rocks and their relationship with host gabbros, they can be divided into three types: (1) Felsic rock with sharp boundaries is formed when felsic melt intrudes into fractures of host gabbros, resulting in minimal interaction between the melt and the wall minerals. (2) Replacive felsic rock, which is characterized by a pseudomorphic replacement of minerals in the host gabbro. This vein type is caused by the replacement of the host mineralogy by minerals in equilibrium with the felsic melts. (3) Felsic rock with diffused boundaries is formed either by infiltration of felsic melt into the solidifying gabbro body or crystallization of interstitial melts. Infiltration modes of felsic melts are likely controlled by the temperature condition of the cooling host gabbros.
Description:
This contribution is part of Du Khac Nguyen’s Ph.D. coursework at Kanazawa University with the funding provided by the Ministry of Education and Training of Vietnam (MOET) under grant number 950/Q -BGD T and Kanazawa University of Japan. This work was supported by Kanazawa University SAKIGAKE project and J-DESC post-cruise support funding.
Keywords:
IODP
;
hole U1473A
;
Atlantis Bank
;
gabbros
;
felsic veins
;
melt-rock interactions
;
oceanic plagiogranite
Repository Name:
Woods Hole Open Access Server
Type:
Article
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