columnar jointing

American  

noun

1. (in basaltic igneous rocks) a series of generally hexagonal columns formed by vertical joints as a result of contraction during cooling.

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Example Sentences

Another well-known exposed example of columnar jointing is the Giant’s Causeway in Ireland.

From Textbooks • Jan. 1, 2017

Cooling lava can contract into columns with semi-hexagonal cross sections called columnar jointing.

From Textbooks • Jan. 1, 2017

Figure 4.14 Figure 4.14 The development of columnar jointing in basalt, here seen from the top looking down.

From Textbooks • Jan. 1, 2015

The later basalts are especially marked by columnar jointing, which determines the famous structures of the Giant’s Causeway and the coast near Bengore Head.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 2 "Anjar" to "Apollo" by Various

Another characteristic of this group of rocks is the perfection with which many of them show prismatic or columnar jointing, a structure often called "basaltic jointing."

From Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 3 "Banks" to "Bassoon" by Various