Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Hagar Al Garda


Occurrence number: 
Longitude: 24, Latitude: 22.5

In the area southwest of Hagar al Garda, and up to 50 km distance, there are a number of upstanding plugs. One such is 1.2 km in diameter and consists of trachyte but has a lenticular body of syenite within it which contains radiating aegirine needles. Some plugs apparently have trachytic margins but cores of porphyritic nepheline microsyenite containing eudialyte. Several circular structures of tilted ferruginous and silicified sandstones probably represent unexposed plugs. There are patches of pyroclastic rocks including trachytic agglomerates and tuffs and phonolitic tuffs associated with some of these structures (Hunting Geology and Geophysics Limited, 1974).


HUNTING GEOLOGY and GEOPHYSICS LTD, 1974. Geology of the Jabal Al Uwaynat area, Libyan Arab Republic. Report to Industrial Research Centre, Department of Geological Research and Mining, Tripoli. Boreham Wood, U.K. (unpublished). 156 pp.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith