Andesite is the most common volcanic rock after basalt . … The primary ingredient of most andesites is andesine, a feldspar of the plagioclase series. Smaller amounts of quartz or minerals rich in iron and magnesium such as olivine , pyroxene, biotite, or hornblende are also present.
What is the economic importance of andesite? Andesite may be used as aggregate or fill, but it is not ideal for concrete applications because it is high in silica, and causes alkali-silica reactivity in the concrete. Andesitic volcanism is associated closely with porphyry copper deposits and it is a host rock for much of the world’s copper ore.
Similarly, What is an andesitic volcano? Andesite is a gray to black volcanic rock with intermediate silica content, typical for lava domes and stratovolcanoes in subduction zones. Andesite is an igneous volcanic rock containing between about 52 and 63 weight % silica (SiO2).
How is andesite formed for kids?
It is formed by the rapid cooling of viscous lava or magma. Perlite has a waxy… extrusive igneous rock that is the volcanic equivalent of granite. … volcanic rock that may be considered a quartz-bearing variety of andesite.
Can andesite be red?
Andesites are typically medium gray and porphyritic, with phenocrysts of white to light gray plagioclase and/or black augite, hornblende, and/or biotite. Some andesites are reddish and some are vesicular.
What is the specific gravity of andesite?
Specific gravities for minerals and other materials.
| Mineral | Specific Gravity |
|---|---|
| Andesite | 2.8 |
| Barite | 4.3 |
| Basalt | 2.9 |
| Bauxite | 2.4 |
How andesite rock is formed? Andesite is a volcanic rock. It is fine-grained because it forms by the rapid cooling of magmas usually when it erupts onto the Earth’s surface and forms lava flows. Andesite forms from magma that contains less quartz (silica) than rhyolite but more than basalt.
Is andesite used in construction? Aggregates are necessary materials for the construction industry. Owing to their favourable properties, andesites are frequently used rock materials; hence, the investigation of their mechanical and aggregate properties has great significance.
What type of rock is andesite?
Andesite most commonly denotes fine-grained, usually porphyritic rocks; in composition these correspond roughly to the intrusive igneous rock diorite and consist essentially of andesine (a plagioclase feldspar) and one or more ferromagnesian minerals, such as pyroxene or biotite.
What are the characteristics of andesitic magma? It ranges in temperature from about 1000oC to 1200oC (1832oF to 2192oF). Andesitic magma has moderate amounts of these minerals, with a temperature range from about 800oC to 1000oC (1472oF to 1832oF). Rhyolitic magma is high in potassium and sodium but low in iron, magnesium, and calcium.
What is the viscosity of andesitic?
Andesitic magmas, in particular, have a wide range of magma viscosities, from 102 to 107 Pa s, which is due to a wide range in phenocryst contents from 0 (phenocryst‐free andesitic melt) to ∼50 vol % (50 vol % rhyolitic melt + 50 vol % phenocrysts).
What type of rock is gneiss? gneiss, metamorphic rock that has a distinct banding, which is apparent in hand specimen or on a microscopic scale. Gneiss usually is distinguished from schist by its foliation and schistosity; gneiss displays a well-developed foliation and a poorly developed schistosity and cleavage.
Is andesite plutonic or volcanic?
Main types of igneous rocks
| Weight % of SiO2 | Plutonic rock type | Volcanic rock equivalent |
|---|---|---|
| 45-53 | Gabbro | Basalt |
| 53-63 | Diorite | Andesite |
| 63-68 | Granodiorite | Dacite |
| 68-75 | Granite | Rhyolite |
What is the hardness of andesite?
The hardness of andesite rocks on the Moh scale is 7.
Is andesite a density? Andesites with it’s normal mineralogy generally have densities between 2.6 to 2.8.
What type of rock is phyllite?
Phyllite
| Type | Metamorphic Rock |
|---|---|
| Texture | Foliated; Fine-grained |
| Composition | Muscovite, Biotite, Quartz, Plagioclase |
| Index Minerals | |
| Color | Shiny Gray |
Why is andesite used in construction?
It is fairly strong, which allows it to be used in road and railway construction, and as fill gravel. The grayish colored rocks seen between railway ties are often andesite or its close relative, basalt. Perhaps the most interesting use of andesite is as proof of volcanic activity on Mars.
What color is andesite? Andesites are typically medium gray and porphyritic, with phenocrysts of white to light gray plagioclase and/or black augite, hornblende, and/or biotite. Some andesites are reddish and some are vesicular.
How strong is andesite?
Andesite
| Renewable | Yes |
|---|---|
| Tool | |
| Blast resistance | 6 |
| Hardness | 1.5 |
| Luminant | No |
How is it formed andesite? Andesite is a volcanic rock. It is fine-grained because it forms by the rapid cooling of magmas usually when it erupts onto the Earth’s surface and forms lava flows. Andesite forms from magma that contains less quartz (silica) than rhyolite but more than basalt.
What are the differences in physical properties between basaltic andesitic and rhyolitic lavas?
BASALTIC magmas have a LOW SILICA content (45-55%) and referred to as MAFIC in composition. RHYOLITIC magma contains more than 65% SILICA and is referred to as FELSIC. ANDESITIC magma is INTERMEDIATE in composition (55-65% SILICA).
What is the solidified rock of andesitic? Viscosity of Magmas
| Summary Table | ||
|---|---|---|
| Magma Type | Solidified Rock | Viscosity |
| Basaltic | Basalt | Low |
| Andesitic | Andesite | Intermediate |
| Rhyolitic | Rhyolite | High |
Sep 14, 2015
What type of volcano produces andesite?
Andesite commonly erupts from stratovolcanoes, where they form small-volume flows that typically advance only short distances down the flanks of a volcano.