What does Trachytic texture imply?
What does Trachytic texture imply?
Trachytic is a texture of extrusive rocks in which the groundmass contains little volcanic glass and consists predominantly of minute tabular crystals, namely, sanidine microlites. Trachytic texture occurs in rocks that are rich in alkalies; hence the vitreous mass of the rocks has a relatively low viscosity.
How do you detect Trachytes?
Trachytes are typically fine-grained and light-colored, but can be black if they consist mostly of glass. They are often porphyritic, with large well-shaped crystals of sanidine in a groundmass containing much smaller imperfect sanidine laths.
What is Shands and Holmes classification?
Shand in 1913 and Holmes in 1917 classified igneous rocks on the basis of free silica into three groups: 1. Silica oversaturated rocks contain more than 66% SiO2, i.e. free quartz mineral is found. Such rocks are also known as acidic or felsic rocks.
What is trachyte made of?
trachyte, light-coloured, very fine-grained extrusive igneous rock that is composed chiefly of alkali feldspar with minor amounts of dark-coloured minerals such as biotite, amphibole, or pyroxene. Compositionally, trachyte is the volcanic equivalent of the plutonic (intrusive) rock syenite.
What is Intergrowth texture?
From Wikipedia, the free encyclopedia. In petrology, micrographic texture is a fine-grained intergrowth of quartz and alkali feldspar, interpreted as the last product of crystallization in some igneous rocks which contain high or moderately high percentages of silica.
What are the 4 classifications of igneous rocks?
Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic. The diagram of Bowen’s reaction series (Figure 7.6) shows that differences in chemical composition correspond to differences in the types of minerals within an igneous rock.
What is in the rock cycle?
The rock cycle is a process in which rocks are continuously transformed between the three rock types igneous, sedimentary and metamorphic. If the sediments are buried under further layers of sediment, they can become lithified to produce a sedimentary rock. Magma is produced when rocks are melted.
What type of rock is trachyte porphyry?
igneous rock
An igneous rock, trachyte primarily consists of alkali feldspars, but also contains plagioclase as well as minor amounts of other minerals, such as olivine, biotite, and pyroxene.
What is a trachyte plug?
Volcanic activity resulted in distinct lava seams interbedded with layers of volcanic ash. Pinnacle Rock, found five Kilometres west of the main visitor area, is a trachyte plug – the core of an extinct volcano.
What is mineral Intergrowth?
The state of interlocking of grains of two different minerals as a result of their simultaneous crystallization.
What is the meaning of trachytic texture?
Definition of trachytic. : of or relating to a texture of igneous rocks in which lath-shaped feldspar crystals are in almost parallel lines.
What is respect in simple words?
In simple words, respect is caring how words and actions may impact others. Respect has two parts: 1) having respect for someone because of how their actions impact others and 2) showing respect by changing your actions to be sure you don’t have a negative impact. Respect is caring enough to consider how words and actions impact others.
What is the scientific name for trachyte?
For the genus of mites, see Trachyetes (mite). Trachyte is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and fine-grained, with minor amounts of mafic minerals, and is formed by the rapid cooling of lava enriched with silica and alkali metals. It is the volcanic equivalent of syenite.
What type of igneous rock is trachyte?
Trachyte is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and fine-grained, with minor amounts of mafic minerals, and is formed by the rapid cooling of lava enriched with silica and alkali metals. It is the volcanic equivalent of syenite.
