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Prof. Dr Bassam A. Abuamarah (M.Phil. & Ph.D.) the Victoria University of Manshester - Machester /United Kingdom.

Professor

Mineralogy, Petrology, Geochemistry of rocks and Ore deposites , Geology ‎& Geophysics Department, College of Science;‎ Former Quality Head Unit, Quality, & Development vice Deanship, Former Research Unit, Postgraduate, and Research vice Deanship,

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Office No. 2b 111, 2nd floor Building # 4, Geology and Geophysics Department, college of science..

Genesis and Petrology of Post-collisional Rare metal-bearing Granites in the Arabian Shield: A case study of Aja Ring Complex, Northern Saudi Arabia

Abuamarah, Bassam A. . 2019

Abstract 8
The Jabal Aja Ring Complex (ARC) is a Late Ediacaran composite pluton of post-collisional A- 9
type granites in the northeastern part of the Arabian Shield. It is an elliptical body with 10
discontinuous ring-shaped outcrops due to later faulting. Field relationships enable the 11
recognition of two main phases of magmatic activity in the ARC. The early phase represents the 12
core of the intrusion (monzogranite, syenogranite, granophyre, and alkali feldspar granite) 13
surrounded by the last phase (alkali volcanics and alkaline/peralkaline granites). The contacts 14
between two phases are gradational and/or sharp, indicating their emplacement within a very 15
short time period before the complete crystallization of the earlier phase. The ARC is alkaline to 16
peralkaline rare-metal granites with the common geochemical characteristics of post-collisional 17
intraplate A-type rocks. The pronounced negative Eu anomalies (Eu/Eu* = 0.14–0.25) reflect 18
extreme magmatic fractionation and perhaps the effects of late fluid–rock interaction. All A-type 19
rocks of the ARC retain a positive Nb-Ta anomaly that increases from the early phase to the 20
most evolved alkaline/peralkaline granites. They define geochemical signatures reflecting their 21
derivation from same magma sources that evolved through fractional crystallization with crustal 22
contamination. The geochemical characteristics of the A-type granites of ARC reflect re-melting 23
Manuscript (Clean) Click here to access/download;Manuscript;Revised manuscript
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2
of previously formed arc material. The mafic microgranular enclaves (MMEs) represent 24
metamorphic rocks derived from/in the deeper part of the crust, and represent the source rocks 25
from which the granitic magma was generated by partial melting. The early phase of magmatism 26
of the ARC represents melts derived from partial melting of lower/middle crustal sources during 27
the post-collisional stage that fractionated to give the various granitic rocks. The absence of 28
mafic xenoliths in the late stage of the ARC indicates that the contribution of crustal sources to 29
the magma generation is absent in the late stage.

Publication Work Type
Research
Magazine \ Newspaper
Journal of Geology
Pages
accepted on line on Nov., 6th, 2019
more of publication
publications

Changes in land use and cover (LULC) are now considered as a significant concern because they have a great impact on biodiversity loss and climate changes.

by Bassam A. Abuamarah, Alshehri F., and Hazim
2023
publications

The Wadi Al-Baroud area, in Egypt's Eastern Desert, exposes Neoproterozoic rocks of the Arabian-Nubian Shield (ANS), including both syntectonic granitoids (granodiorite and tonalite) and post-…

by Bassam A. Abuamarah, Hassan Alzahrani, Marian J. Matta, Mokhles K. Azer, Paul Asimow, Mahmoud H. Darwish
2023
Published in:
Journal of African Earth Sciences
publications
by 5. Mokhles K. A., Bassam A. Abuamarah, Mahmoud M. Srour, Simon A. Wilde, and Ramadan M. Gomaa
2023
Published in:
The Journal of Geology