| 释义 |
carbonatite, n. Petrogr.|kɑːˈbɒnətaɪt|
[ad. G. Karbonatit (W. C. Brøgger 1921, in Skrifter Vidensk.-Selsk. Kristiania (Mat.-natur. Kl.) II. 350), f. Karbonat carbonate n.: see -ite1.]
Any igneous rock composed chiefly of carbonates rather than silicates.
1924Amer. Jrnl. Sci. VIII. 2 The intrusion of carbonatite took place, in part at least, contemporaneously with that of ijolite. 1965A. Holmes Princ. Physical Geol. (ed. 2) xxix. 1077 We know nothing about the origin of the carbonatites that are so curiously involved in uplifts, rift valleys and alkaline rocks. 1977A. Hallam Planet Earth 164/3 Ancient carbonatite intrusions are composed of calcium, magnesium or iron carbonates; though at least one volcano..has in recent times emitted ashes and flows of sodium carbonate. 1988Nature 22 Sept. 295/2 Carbonatites, rare magmatic carbonate-rich rocks, are usually associated with silica-undersaturated rocks. |