| 释义 |
shoshonite Petrogr.|ʃəʊˈʃəʊnaɪt|
[f. the name of the Shoshone River, Wyoming (cf. Shoshone) + -ite1.]
A type of basaltic rock varying quite widely in composition and distinguished by containing, in addition to augite, labradorite, and usu. olivine, significant amounts of potassium feldspar.
1895J. P. Iddings in Jrnl. Geol. III. 938 The classes will be described in the order just given under the names: Absarokite, Shoshonite and Banakite. Ibid. 943 The rocks classed as shoshonites are more numerous than the absarokites, and embrace a somewhat wider range of composition. They occupy the middle ground, as it were, in the series. 1937Holmes & Harwood Volcanic Area of Bufumbira (Mem. Geol. Survey Uganda No. 3) xii. 269 The xenoliths of the shoshonites of Sabinyo include aggregates referable to kentallenite and olivine-monzonite. 1976Nature 12 Feb. 472/1 The calc-alkaline lavas..range from ‘normal’ basalts, basaltic-andesites and andesites to highly potassic varieties having all the compositional and modal characteristics of shoshonites.
Hence shoshoˈnitic a., resembling or consisting of shoshonite.
1937Holmes & Harwood Volcanic Area of Bufumbira (Mem. Geol. Survey Uganda No. 3) ii. 16 These rocks are more feldspathic than the shoshonitic absarokites of Muhavura and Mgahinga. 1964G. A. Joplin Petrogr. Austral. Igneous Rocks vii. 90 The different shoshonitic rocks show many common characteristics. |
