Magmatic Differentiation and Silica Saturation Trend in the Alkaline Volcanic Suite of Jabal Al Hasawna, West Central Libya

Malik Othman

doi:10.54172/zvtpy966

Authors

Malik Othman Department of Geology, Misurata University, Libya Author

DOI:

https://doi.org/10.54172/zvtpy966

Keywords:

Magmatic differentiation, Major elements, Volcanic, Al Hasawna, Phonolites

Abstract

Magmatic differentiation is one of the important factors which lead to the diversity seen in igneous rocks. This work aims to understand the processes that occurred to the alkaline magma that produced these volcanic rocks in the Jabal Al Hasawna region. The study was conducted as a follow-up to a preliminary report done by the Libyan Industrial Research Centre in 1978 on the volcanic rocks in the study area. The study concentrated on the major elements of the rocks being examined. The research paper is based on twenty-four samples, classified as one quartz-trachyte, five trachyte, nine phonolite and eight nepheline-phonolite samples. The work indicates magmatic differentiation processes of undersaturated alkaline melt differentiated into oversaturated alkaline magma formed a volcanic lava flow, perhaps at multiple batches. The study concluded that differential processes occurred for the remaining magma, rather than primitive processes, claiming that the mantle signature may not have been present, although relying on major elements alone may not be sufficient to track this matter. Therefore, the study needs more data relating to rare elements, and this is one of the limitations of this work.

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