A fine-grained, igneous rock composed essentially of plagioclase feldspar and quartz, with or without hornblende and biotite. Included in the group of rocks collectively named felsite.
A volcanic rock containing 63-68% silica with a high viscosity when in a molten state.
one of the most common rock types associated with enormous Plinian-style eruptions; dacite lava consists of 63 to 68 percent silica, erupts at temperatures of between 800 and 1000°C, and is often light gray in color after cooling
A fined grained extrusive rock equivalent to the intrusive granodiorite.
a thick, igneous rock ejected at the earth's surface
Light-colored, silica-rich volcanic rock (63-68 percent SiO2) of high viscosity when in a molten state; eruptions are commonly explosive and may produce voluminous tephra, pyroclastic flows, and lava domes.
a gray volcanic rock containing plagioclase and quartz and other crystalline minerals
Dacite lava is most often light gray, but can be dark gray to black. Dacite lava consists of about 63 to 68 percent silica (SiO2). Common minerals include plagioclase feldspar, pyroxene, and amphibole. Dacite generally erupts at temperatures between 800 and 1000°C. It is one of the most common rock types associated with enormous Plinian-style eruptions. When relatively gas-poor dacite erupts onto a volcano's surface, it typically forms thick rounded lava flow in the shape of a dome.
Volcanic rock that contains between 63 and 72 weight percent silica. Dacites are typically gray to pink in color and contain visible crystals of plagioclase, hypersthene, and hornblende (Figure 5).
Volcanic rock (or lava) that characteristically is light in color and contains 62% to 69% silica and moderate a mounts of sodium and potassium.
A fine-grained, extrusive (volcanic) rock, intermediate in color and composition between basalt and rhyolite.
A common volcanic rock that forms pumice, or glassy lava. Dacite contains about 65% silica. Dacite lava is very sticky, and often forms domes or stubby flows.
A volcanic rock similar to andesite, but normally containing more quartz.
Dacite is a type of volcanic rock that is light-colored and rich in silica (63 to 68 percent).
A fine-grained volcanic rock with the same general composition as andesite, but having less of the feldspar mineral Calcic Plagioclase and more quartz.
Igneous volcanic rock, less mafic than andesite, typically fine-grained and light in color; rough volcanic equivalent of granodiorite.
volcanic rock, mesocratic, with a microlitic or porphyritic texture, composed of quartz, plagioclase (andesine), biotite, amphibole (green hornblende) in a vitric groundmass. In paleovolcanics this vitric groundmass is recrystalized with chlorite, epidote....
A volcanic rock similar to a rhyolite, but with a lower silica content.
A type of volcanic rock intermediate between andesite and rhyolite. Mount Tauhara at Taupo and Mount Edgecumbe (Putuaki) near Kawerau are examples of dacite volcanoes.
volcanic rock composed of oligoclase feldspar and other associated minerals: the volcanic equivalent of granodiorites
A fine grained volcanic rock, the extrusive equivalent of granodiorite;
An extrusive igneous rock, in which the principal minerals are plagioclase, quartz, pyroxene or hornblende or both with minor amounts of biotite and sanidine.
Dacite (IPA: ) is a high-silica igneous, volcanic rock. It is intermediate in compositions between andesite and rhyolite, and, like andesite, it consists mostly of plagioclase feldspar with biotite, hornblende, and pyroxene (augite and/or enstatite). It has an aphanitic to porphyritic texture with quartz as rounded, corroded phenocrysts, or as an element of the ground-mass.
