Sentence Examples


  • The principal rocks are andesites, but trachytes and basalts are also common.
  • The rocks are mainly basalts and andesites, together with trachytes and phonolites, and some of the basaltic flows are of enormous extent.
  • 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.
  • Trachytes, rhyolites, andesites and basalts occur, and a definite order of succession has been made out in several areas; but this order is not the same throughout the chain.
  • Basic lavas, with andesites, trachytes, tuffs and agglomerates are the most common Scottish rocks of this period.
 

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