0 a type of black rock that comes from a volcano
1 a type of black rock that comes from a volcano (= mountain that explodes and throws out hot rocks)
It was built upon a conical peak of basalt, and was surrounded by four deep valleys, one on each side, another in front, and the fourth in the rear.
The hills which bound the valley of the creek are basalt, sandstone, and schist.
The right bank of the river rose into steep cliffs of basalt, under which the clustered fig tree, with its dense foliage, formed a fine shady bower.
The soil is chiefly volcanic ash, disintegrated basalt and alluvium.
The spot was quite surrounded by high sloping walls of basalt, except to the west, where they opened in a three-foot cleft to the shore, and the ground was strewn with slabs and boulders of granite and basalt.
This lends support to a controlling influence for lithospheric rifting zones on continental flood basalt generation and emplacement.
We have undertaken three independent field tests to determine whether the magnetization of the andesite and basalt sheets is primary.
These conglomerates are composed of clasts of basalt, volcaniclastic sandstone, alkaline lava and sub-rounded chert.
