Volcanic igneous rock originates from magma that erupts, as either lava or as tephra, and turns solid on the earth's surface. Plutonic igneous rock comes from magma that intrudes within the earth, deep underground, and cools and crystallizes there. May contain a few minerals common in mafic rocks, listed above Plutonic igneous rock comes from magma that intrudes within the earth, deep underground, and cools and crystallizes there.Volcanic igneous rock originates from magma that erupts, as either lava or as tephra, and turns solid on the earths surface. May contain a few minerals common in intermediate rocks, listed above May contain a few minerals common in felsic rocks, listed above Variable (depending on rock fragments and ash content) Originates from pyroclastic (explosive) eruptions Originates from cooling too rapid to allow crystal lattices Note: basalt with a smaller number of holes, known as vesicles, is called vesicular basalt. Plotting The main strength of GCDkit is arguably the wealth of built-in publication-quality plots that can be exported into a number of data formats (including PostScript, WMF, JPG, PNG. Glass (may contain a few minerals common in mafic rocks, listed above) normative albite, quartz and orthoclase to be plotted on a AbQzOr ternary diagram) or copied to a clipboard, savedorexportedtoHTML,DBF,XLS,MDBortextfiles. Glass (may contain a few minerals common in felsic rocks, listed above) Originates in gas-charged volcanic eruptions, commonly Originates in lava flows (or very shallow intrusions), Na-plagioclase, amphibole, pyroxene, biotiteĬa-plagioclase, pyroxene, olivine, amphibole Na-plagioclase, quartz, amphibole, biotite, orthoclase Originates in deep intrusions, which cool and crystallize Na-plagioclase, orthoclase, quartz, biotite, amphibole, muscovite Originates from water-rich intrusions, which cool and crystallize