Three basic types of magma: 1  Mafic or Basaltic-- SiO2 45-55 wt%, high in Fe, Mg, Ca, low in K, Na. 2  Intermediate or Andesitic-- SiO2 55-65 wt%, intermediate. in Fe, Mg, Ca, Na, K. 3  Felsic or Rhyolitic-- SiO2 65-75%, low in Fe, Mg, Ca, high in K, Na.
intensity noun [U]. âº the âquality of being âextreme in âstrength or âforce: Simone âsings with âemotional intensity. The âlight âhit us with such intensity that we âducked. âº art Intensity in a âwork of âart âdescribes the âstrength of the âcolor, âsound, âlight, or âfeeling. (Definition of intensity from the Cambridge Academic Content Dictionary Â© Cambridge University Press).
a. a measure of field strength or of the energy transmitted by radiation. See radiant intensity, luminous intensity. b. (of sound in a specified direction) the average rate of flow of sound energy, usually in watts, for one period through unit area at right angles to the specified direction.