Stratigraphy and lithology of Miocene silicic volcanics in the Shama Area, Saudi Arabia
Other Title(s)
استراتيجرافية و ليثولوجية البركانات السيليسية الميوسينية في منطقة شاما بالمملكة العربية السعودية
Joint Authors
al-Uwaydi, Khalid
Rangon, Jean Philippe
Source
Journal of King Abdulaziz University : Earth Sciences
Issue
Vol. 3, Issue 1 (31 Dec. 1990), pp.157-164, 8 p.
Publisher
King Abdulaziz University Scientific Publishing Center
Publication Date
1990-12-31
Country of Publication
Saudi Arabia
No. of Pages
8
Main Subjects
Earth Sciences, Water and Environment
Abstract EN
Volcanic rocks of Jabal Shama and Harrat Shama are considered to be remnants of Early Miocene volcanism related to the opening of the Red Sea rift.
This type of volcanism is characterised by the local occurrence of felsic lava flows and pyroclastics.
The upper part of the succession is composed of slightly silicified flow-banded rhvolite; brec- ciated and devitrified lavas are also common.
Beneath the rhyolite is the Green Tuft unit, comprising two main lithologic types : 1.
At the base of the sequence, massive to brecciated felsic lava How.
strongly hydrother- malised.
overlies locally exposed basalt.
Perlite lenses and layers, corresponding to hydrated vitrophyric lavas and showing various textures, are commonly intercalated with hydrotnor- malised felsic lava flows.
2.
Extensive ground surge deposits and pumice flows, the representatives of ignimbritie explosive volcanism at distant centres or vents, from the upper part of this unit.
The Green l uff unit is.
in general, poorly exposed elsewhere, but has been preserved in the Shama area by the overlying felsic lava flows.
An erosional unconformity at the top of the formation and the lack of intense hydrothermal alteration in the upper volcanics indicate a pause in volcanic ac- tivity between the deposition of these two main volcanic units.
American Psychological Association (APA)
Rangon, Jean Philippe& al-Uwaydi, Khalid. 1990. Stratigraphy and lithology of Miocene silicic volcanics in the Shama Area, Saudi Arabia. Journal of King Abdulaziz University : Earth Sciences،Vol. 3, no. 1, pp.157-164.
https://search.emarefa.net/detail/BIM-400679
Modern Language Association (MLA)
Rangon, Jean Philippe& al-Uwaydi, Khalid. Stratigraphy and lithology of Miocene silicic volcanics in the Shama Area, Saudi Arabia. Journal of King Abdulaziz University : Earth Sciences Vol. 3, no. 1 (1990), pp.157-164.
https://search.emarefa.net/detail/BIM-400679
American Medical Association (AMA)
Rangon, Jean Philippe& al-Uwaydi, Khalid. Stratigraphy and lithology of Miocene silicic volcanics in the Shama Area, Saudi Arabia. Journal of King Abdulaziz University : Earth Sciences. 1990. Vol. 3, no. 1, pp.157-164.
https://search.emarefa.net/detail/BIM-400679
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references : p. 163
Record ID
BIM-400679