| 释义 |
hedrumite Petrogr.|ˈhɛdrəmaɪt|
[a. G. hedrumit (W. C. Brögger 1890, in Zeitschr. f. Kryst. und Min. XVI. 40), f. Hedrum, the name of a village north of Larvik, Norway + -ite1.]
A hypabyssal porphyritic igneous rock having a trachytic texture and consisting essentially of a potash-feldspar with small amounts of pyribole and usu. also nepheline.
1896J. F. Kemp Handbk. Rocks 141 Hedrumite, a name proposed by Brögger for certain syenitic rocks that are poor or lacking in nepheline, but that have a trachytic texture. 1920A. Holmes Nomencl. Petrol. 116 Hedrumite... A leucocratic variety of alkali-syenite containing accessory nepheline. 1938A. Johannsen Descr. Petrogr. Igneous Rocks IV. i. 25 Hedrumites..are essentially pulaskite-porphyries with a coarse trachytic texture. Brögger defined them as the mineralogical and chemical hypabyssal-trachytoid-equivalents of the pulaskites. 1964Mineral. Abstr. XVI. 574/1 Senonian hedrumites cutting somewhat earlier andesites and pyroclastics have been found..in Bulgaria. |