metabasite, n. Geol.
Brit. /ˌmɛtəˈbasʌɪt/, /ˌmɛtəˈbeɪsʌɪt/, U.S. /ˌmɛdəˈbæˌsaɪt/, /ˌmɛdəˈbeɪˌsaɪt/
[‹ meta- prefix + bas- (in basic adj.) + -ite suffix1 (see quot. 1907).]
A fully metamorphosed form of a basic rock such as basalt or dolerite.
| 1907J. J. Sederholm in Bull. Comm. Géol. Finlande 4 92 Metabasite = metamorphosed basic rocks, ranging from uralite-diabases and uralite-porphyries to amphibolic schists. The designation has been suggested by dr V. Hackman. 1940 F. F. Grout J. F. Kemp's Handbk. Rocks (ed. 6) 286 Metabasite, metamorphosed dolerite. 1977 A. Hallam Planet Earth 175 As most rocks within a broad chemical grouping—such as pelites or metabasites—have a number of minerals in common, reactions between the common set of minerals can be identified in many different individual rocks. 1997 Science 4 Apr. 91/1 We describe and interpret an occurrence of cristobalite in high-pressure..granulite facies garnet from a Middle Proterozoic..metabasite. |