basalts's Usage Examples:

Plateau Basalts.

The geological sequence of events appears to have been the following: - After the deposition of the Eocene (or Oligocene) limestone - which reposes upon a floor of basalts and trachytes - basalts and basic tuffs were ejected, over which, during a period of very slow depression, orbitoidal limestones of Miocene age - which seem to make up the great mass of the island - were deposited; then elapsed a long period of rest, during which the atoll condition existed and the guano deposit was formed; from then down to the present time there has succeeded a series of sea-level subsidences, resulting in the formation of the terraces and the accummulation of the detritus now seen on the first inland cliff, the old submarine slope of the island.

Ancient schists occur on the east coast south of Angmagssalik, and basalts and schists are found in Scoresby Fjord.

They are mostly true felspar basalts, but a few contain nepheline in addition to the felspar.

Its presence contributes to the dark colour of many basalts and other basic rocks, and may cause them to disturb the compass.

These rocks were followed by the outpouring of the extensive older basalts in the Great Valley of Victoria and on the highlands of eastern Victoria, and also in New South Wales and Queensland.

The rocks are mainly basalts and andesites, together with trachytes and phonolites, and some of the basaltic flows are of enormous extent.

The principal rocks are andesites, but trachytes and basalts are also common.

The deposits of the actual valley here, belonging to the Miocene group of the Tertiary system, are older than the deposits either farther up or farther down the river; but they are contemporaneous with the basalts of the Rhine, which at Coblenz and in the peaks of the Seven Mountains also contribute to the scenic charm of the river.

The volcanic series include the rhyolite of Nell Island, some obsidian, and the sheets of basalts which form the Cloudy Mountains, Mount Dayman and Mount Trafalgar (an active volcano), and also cover wide areas to the south and west of the Owen Stanley Range.

Synonyms:

oligoclase, plagioclase, pyroxene, volcanic rock,