Alkaline Rocks and Carbonatites of the World

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

Kaituma

stripes

Occurrence number: 
068-00-001
Country: 
Guyana
Location: 
Longitude: -59.83, Latitude: 7.67
Carbonatite: 
No

The Kaituma intrusion of peralkaline quartz syenite covers about 70 km2 and appears to grade westwards into biotite granite. It comprises microcline perthite, albite-oligoclase, quartz, aegirine, arfvedsonite, biotite and accessory sphene, orthite, magnetite and apatite. Pegmatites which cut the intrusion have high radioactivity owing to the presence of euxenite, samarskite, uranothorite and titanian betafite.

Age: 
2065±100 Ma was obtained on aegirine-augite by K-Ar (Snelling and McConnell, 1969, Table 3).
References: 

ALLEN, P.M. 1964. The younger granite group of British Guiana. Report of 22nd Session, International Geological Congress, India, 10: 539-52.
SNELLING, N.J. and MCCONNELL, R.B. 1969. The geochronology of Guyana. Records, Geological Survey of Guyana, 6: XI, 1-26

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