Volcanic lavas are called felsic lavas ... will crystallize out first, leaving an increasingly felsic composition. In his work on the formation of minerals from magma, N. identified the sequence in ...

The cause of episodes of unrest at caldera volcanoes is often unclear. Analysis of the sulfur composition of gas ... forming diverse felsic melts, according to geochemical and petrological data ...

"The diverse volcanism is associated with felsic volcanic compositions which are unlike any other suite of recognized deposits or volcanic region on Mars," Michalski and colleagues write ...