See Also: tholeiite(dictionary)

tholeiite (iou)



tholeiite noun. M19.
[from Tholei (now -ey), a village in the Saar, Germany + -ITE1.]
Geology. Orig., an olivine-poor basaltic rock containing plagioclase feldspar, pyroxene, and glass. Now, a basaltic rock containing augite and a calcium-poor pyroxene (pigeonite or hypersthene), and with a higher silica and lower alkali content than an alkali basalt.
tholeiitic adjective E20.