Crossword clues for andesite
The Collaborative International Dictionary
Andesite \An"des*ite\, n. (Min.) An eruptive rock allied to trachyte, consisting essentially of a triclinic feldspar, with pyroxene, hornblende, or hypersthene.
n. (context geology English) A class of fine-grained intermediate igneous rock, of volcanic origin, containing mostly plagioclase feldspar.
n. a dark gray volcanic rock
Andesite ( or ) is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite, and ranges from 57 to 63% silicon dioxide (SiO) as illustrated in TAS diagrams. The mineral assemblage is typically dominated by plagioclase plus pyroxene or hornblende. Magnetite, zircon, apatite, ilmenite, biotite, and garnet are common accessory minerals. Alkali feldspar may be present in minor amounts. The quartz- feldspar abundances in andesite and other volcanic rocks are illustrated in QAPF diagrams.
Classification of andesites may be refined according to the most abundant phenocryst. Example: hornblende-phyric andesite, if hornblende is the principal accessory mineral.
Andesite can be considered as the extrusive equivalent of plutonic diorite. Characteristic of subduction zones, andesite represents the dominant rock type in island arcs. The average composition of the continental crust is andesitic. Along with basalts they are a major component of the Martian crust. The name andesite is derived from the Andes mountain range.
Usage examples of "andesite".
Sinclair objected that the mortar was made of andesite, a volcanic rock not often found in the deep gravels at Table Mountain.
Medium grey andesite, an igneous volcanic rock, speckled with crystals of dark minerals, knobbed with hard protrusions.
Tuff is much softer than basalt and andesite, and over the years this exposed layer has eroded away, leaving us with our wonderful hotel.
Suhl, about forty miles to the east, to see igneous granites, rhyolites, and andesites, as well the copper mines of nearby Goldlauter.
But modern geologists report that in the region north of Table Mountain there are four sites that are just as old as the prevolcanic auriferous gravels and contain deposits of andesite.
Her world was four and a half billion years old, and she had a vocabulary newly full of strike-slip faults, cactoliths, andesite, and monzonite, and she made tilting slipping shapes with her hands to show us how the mountains came about.
The bedded volcanic rocks which form a series of ridges trending north-west comprise porphyritic basalts, andesite, and, near Port Luchdach, brownish trachyte.
The pale vermilion tones of the walls, staircases and vertical columns were in sharp contrast to the domed masses of the chocolate and violet andesite cliffs, cut by blue and grey porcelain-like paths of cast syenite.
Erosion had carved the tuff wherever bracks in the andesite exposed it, forming the tunnel-bottomed ravines, and also revealing great seams of caliche, trapped between the two layers.
If there's time, the students might venture as far as Suhl, about forty miles to the east, to see igneous granites, rhyolites, and andesites, as well the copper mines of nearby Goldlauter.
If there's time, the students might venture as far as Suhl , about forty miles to the east, to see igneous granites, rhyolites, and andesites, as well the copper mines of nearby Goldlauter.