> as lemmas

1876 J. D. Dana in Amer. Jrnl. Sci. 111 121 The rocks are..Metamorphic doleryte, metamorphic diabase, and metamorphic melaphyre... To distinguish these metamorphic rocks from the igneous of the same composition, they are named, on my suggestion, metadoleryte, metadiabase, and metamelaphyre. The examples are part of a long series of rock species which have representatives both among igneous (or intrusive) and metamorphic rocks. Other kinds are dioryte and metadioryte, syenyte and metasyenyte, felsyte and metafelsyte, etc.

1920 A. Holmes Nomencl. Petrol. 154 Meta-, a prefix used before the names of igneous rocks to signify that the mineral and chemical composition of the latter have been modified by alteration.

1942 M. P. Billings Struct. Geol. xii. 215 Metasediments, metavolcanics, and meta-igneous rocks are metamorphic rocks derived, respectively, from sedimentary, volcanic, and igneous rocks.

1959 Bull. Geol. Soc. Amer. 70 1699 Nearly all outcrops of the metadiorite are deeply weathered.

1960 Ecol. Monogr. 30 281/1 Sighting across the valley one may observe remnants of the surface in the lower, metavolcanic mountains.

1969 Geochem. Internat. 6 Suppl. 408 The correlations of U and Th with composition for the metagranites show that these two radioelements behave independently.

1973 Nature 21 Sept. 120/1 The metasediments occur in a (refolded) syncline among granitic gneisses.

1988 Nature 22 Dec. 736/1 Only the reservoir represented by the meta-igneous xenoliths is a viable candidate.

1993 Jrnl. Petrol. 34 462 These bodies intrude a variety of metasedimentary and metavolcanic rocks in several fault-bounded, northeast-trending terranes.

1994 Biogeochemistry 26 85 Several natural bedrock surfaces (metagranites) covered with moss or lichen were leached with HCl solutions.