Also found in: Encyclopedia, Wikipedia.


 (tō′lə-īt′, thō′-)
Any of a series of igneous rocks similar in composition to basalt but having more silica and iron and less aluminum.

[After Tholei (Tholey), municipality in Saarland, Germany, where it is found.]

tho′lei·it·ic (-ĭt′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


relating to, characteristic of or resembling tholeiite
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
This Archaean greenstone belt is predominantly composed of tholeiitic basalt lava and volcaniclastic deposits, ultramafic rocks, felsic volcanic rocks and sediments surrounded by younger Archaean granitoids.
The western segment is dominated by a thick sequence of tholeiitic basalt with common BIF units, typical of the Southern Cross Granite Greenstone Terrane (Wyche, 1999).
It is important to note that K shows maximum positive loading (0.814) in the sixth component, probably due to the tholeiitic nature of the BO.
And as originated from the seabed basalt eruption in the Tethys ridge and the plate subduction that led to the ultimate close of the Hymalayas-Tethys Ocean, it has typical character of the tholeiitic basalt in the mid-ocean ridge, providing evidence of collision between the Eurasian and the Indian Plate.
Basalt samples from the Ketchum Brook Formation are similar in that the four samples span the tholeiitic, transitional, and calc-alkaline fields.
The eruptive products were alkali and tholeiitic basalts, trachyte and comendite lavas, and pyroclastic equivalents [5].
The second case regards volcanic glasses with extremely low total Sr content (i.e., tholeiitic).
Recent classification (Branca & al., 2011) grouped this products in the Basal Tholeiitic Supersynthem and the literature data are agree to date the eruptive phenomena at about 500000 years ago.
Leaching experiments have been conducted on biotite granites and tholeiitic basalts at room temperature and under acidic conditions.
Mineral-melt interaction during late stage crystallization has been identified in rocks of variable geochemical affinity, including tholeiitic (Gillis, 1996; Tribuzio et al., 1999b, 2000; Coogan et al., 2001) and continental calc-alkaline magmas, the latter sometimes associated with post-collisional geodynamic settings (Monjoie et al., 2005; Tiepolo and Tribuzio, 2005; Renna et al., 2006).