Definition of tholeiite in English:
noun[mass noun] Geology
A basaltic rock containing augite and a calcium-poor pyroxene (pigeonite or hypersthene), and with a higher silica content than an alkali basalt.
- 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.
- 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.
mid 19th century: from Tholei, the name of a village (now Tholey) in the Saarland, Germany, + -ite1.
- Example sentences
- In the Canaries, the lavas are much more compositionally varied in each of these stages, ranging from tholeiitic basalts to phonolites and trachytes.
- A tholeiitic suite of dolerite dykes in the southwestern Borrowdale Volcanic Group is a separate, later magmatic event.
- The Whin Sill complex is a large tholeiitic quartz dolerite intrusion in northern England.
What do you find interesting about this word or phrase?
Comments that don't adhere to our Community Guidelines may be moderated or removed.
Most popular in the US
Most popular in the UK
Most popular in Australia
Most popular in Malaysia
Most popular in Pakistan