stripes
This large quarry in massive Ottawa limestone contains carbonatite dykes that occupy regionally developed shatter zones at intervals of 50-100 m. They parallel a set of normal faults trending approximately east-west. The largest dyke, the most northerly, ranges in thickness from 1.2 to 0.3 m. The dyke has a 1-2 cm wide, fine-grained margin and a massive to slightly flow-banded interior containing phenocrysts and xenocrysts. The phenocrysts include two generations of phlogopite and apatite up to 1 cm diameter and a wide range of xenocrysts derived from the Precambrian basement. The matrix, which is essentially carbonate, is fine-grained and varies from vesicular to trachytic. Chemical analyses indicate the carbonate to be dolomitic with high tenors of La, Ce, Nb, Mo and Sr. The larger Precambrian xenoliths are silica under-saturated and sodic. This is the Eastview occurrence of Tuttle and Gittins (1966, p. 528).
BOLTON, T.E. and LIBERTY, B.A. 1972. 24th International Geological Congress, Canada. Field Excursion Guidebook, B-23 to B-27: 20-2.
TUTTLE, O.F. and GITTINS, J. 1966. Carbonatites. John Wiley, New York. 591pp.