| 释义 |
Definition of tholeiite in English: tholeiitenoun ˈθəʊlɪʌɪt mass nounGeology A basaltic rock containing augite and a calcium-poor pyroxene (pigeonite or hypersthene), and with a higher silica content than an alkali basalt. Example sentencesExamples - Trace element data and isotopic analysis demonstrate that the arc is composed of islandarc tholeiite and ocean-island basalts and calc-alkaline arc-type extrusive rocks.
- I decided on a ten-minute diversion, a loop round the hill to a point on the straight and very narrow line of tholeiite that cuts across the country.
- Except for its lower degree of partial melting (hence, a higher content of volatile matter), alkali basalt is thought to have an origin similar to that of tholeiite.
- In the Pechenga-Varzuga volcanosedimentary belt, alkali basalts eruptions about 2.2 Ga in age gradually gave way to tholeiite pillow lavas, Fe-picrite flows and Ti-rich basalts with ages around 1.98 Ga.
- Among these, the best candidates for LIPs are thick tholeiite sequences that contain komatiites.
Derivatives adjectiveˌθəʊlɪˈɪtɪk Geology In the Canaries, the lavas are much more compositionally varied in each of these stages, ranging from tholeiitic basalts to phonolites and trachytes. Example sentencesExamples - The Whin Sill complex is a large tholeiitic quartz dolerite intrusion in northern England.
- Carboniferous volcanism, occurring at converging plates margins, both at the Appalachian and at the Ouachita margins, was decidedly not tholeiitic.
- A tholeiitic suite of dolerite dykes in the southwestern Borrowdale Volcanic Group is a separate, later magmatic event.
- Metabasic rocks throughout the Moine outcrop display a tholeiitic chemistry comparable with modern mid-ocean basalts.
Origin Mid 19th century: from Tholei, the name of a village (now Tholey) in the Saarland, Germany, + -ite1. |