Alkaline Rocks and Carbonatites of the World

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

Campos Do Jordao

stripes

Occurrence number: 
025-00-091
Country: 
Brazil
Region: 
Sao Paulo
Location: 
Longitude: -45.55, Latitude: -22.75
Carbonatite: 
No

A series of widely spaced, scattered dykes, up to a metre thick, are aligned northeast-southwest and cut variable Precambrian gneisses. Rock types represented include nepheline-phyric tinguaite, porphyritic shonkinite and monchiquite.

Age: 
80 Ma (Ulbrich and Gomes, 1981).
References: 

MELCHER, G.C. and MELCHER, B.A. 1972. Novas ocorrencias de rochas alcalinas no Estado de Sao Paulo. Anais Congresso Brasileiro de Geologia, 26(1): 216-7.
ULBRICH, H.H.G.J. and GOMES, C.B. 1981. Alkaline rocks from continental Brazil. Earth Science Reviews, 17: 135-54

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