What are the factors that affect texture of igneous rocks? The texture in igneous rocks depends on the following four factors: i) Viscosity of magma ii) Rate of cooling iii) The order of crystallization of the constituent minerals. iv) The relative rates of growth of the constituent minerals.
What affects the texture of igneous rocks?
In this way, what affects the texture of igneous rocks? The main factors that can affect the texture of an igneous rock are the location and cooling rate of the hot magma that forms the rock. Subsequently, question is, what factors affect the physical appearance of igneous rocks?
How does the separation of minerals affect the composition of igneous rocks?
The separation of minerals by mechanisms such as crystal settling result in igneous rocks having a wide variety of compositions. When a rock is mechanically weathered, how does its surface area change?
What does a porphyritic texture indicate about the history of igneous rocks?
What does a porphyritic texture indicate about the history of an igneous rock? The rock experienced a two-stage cooling history: cooling at depth forming larger crystals, being brought to the surface by magma, the remaining liquid cools more quickly forming smaller crystals.
What are the basic compositional groups of igneous rocks?
List and distinguish among the four basic compositional groups of igneous rocks. Granitic (felsic) - rocks are composed mostly of light-colored silicate minerals potassium feldspar and quartz. ex: granite and rhyolite Andesitic (intermediate) - contains plagioclase feldspar and amphibole. ex: andesite, diorite.
What factors influence the texture of an igneous rock quizlet?
The three factors that influence the textures of igneous rocks are the speed of cooling, the silicate content, and the water content. The speed of cooling affects the texture because the faster the rate of cooling, the smoother the rock will be (finer texture, aphanitic).
How is texture determined in igneous rocks?
What determines igneous rock texture? It all comes down to the rate at which the rock cools. Other factors include the diffusion rate, which is how atoms and molecules move through the liquid.
What factors affect the type of igneous rock?
The type of igneous rocks that form from magma is a function of three factors: the chemical composition of the magma; temperature of solidification; and the rate of cooling which influences the crystallization process.
What are the texture of igneous rocks?
Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification. There are six main types of textures; phaneritic, aphanitic, porphyritic, glassy, pyroclastic and pegmatitic.
What factors influence the texture of sediments?
Textures of Sedimentary RocksThe strength of the wind or water currents that carry and deposit the sediment. ... The distance transported or time in the transportation process. ... Biological activity with the sediment prior to diagenesis. ... The chemical environment under which diagenesis occurs.
What are the factors explaining texture?
Explanation: The term texture is defined as the mutual relationship of different mineralogical constituents in a rock. It is determined by the size, shape and arrangement of these constituents within the body of the rock.
What are the two major factors that influence the way an igneous rock will form?
The two major factors that influence the creation of igneous rocks are the original rock that was melted and the cooling history of the molten rocks.
What are the 3 main characteristics of igneous rock?
Characteristics of Igneous RocksThe igneous form of rocks does not include any fossil deposits. ... Most igneous forms include more than one mineral deposit.They can be either glassy or coarse.These usually do not react with acids.The mineral deposits are available in the form of patches with different sizes.
How is the texture of an igneous rock related to the rate at which it cooled?
There are two fundamental properties of igneous rocks that are used to assign a name. Texture -- the size of the crystals can be crudely related to the rate of cooling. The higher the rate of cooling the smaller the size of the crystals.
How do you describe igneous textures?
The texture of an igneous rock made up entirely of crystals big enough to be easily seen with the naked eye is phaneritic. Phaneritic texture is sometimes referred to as coarse-grained igneous texture. Granite, the most well known example of an intrusive igneous rock, has a phaneritic texture.
What is texture of igneous rock with example?
Examples of aphanitic igneous rock include basalt, andesite and rhyolite. Glassy or vitreous textures occur during some volcanic eruptions when the lava is quenched so rapidly that crystallization cannot occur. The result is a natural amorphous glass with few or no crystals. Examples include obsidian and pumice.
What are the 4 textures and compositions of igneous rocks?
Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic.
How do igneous rocks form?
Igneous rocks form when magma or lava cools and solidifies. Sedimentary rocks form when sediments become compacted and cemented. Metamorphic rocks form when existing rocks are changed by heat, pressure, or solutions.
What happens when igneous rock is exposed to erosion?
When large amounts of igneous rock that formed deep underground are exposed by erosion, a process called sheeting occurs, where concentric slabs break loose. This is partially due to the reduction in pressure the rock is under at the surface , the igneous rock expands and fractures.
How does mechanical weathering work?
Mechanical weathering breaks rock into smaller pieces exposing more surface area. Mechanical weathering adds to the effectiveness of chemical weathering because more area is exposed and chemical weathering occurs mainly on exposed surfaces. Explain how water can cause mechanical weathering.
What is magmatic differentiation?
Magmatic differentiation is where the formation of one or more secondary magmas from a single parent and possess different compositions. The separation of minerals by mechanisms such as crystal settling result in igneous rocks having a wide variety of compositions.
What breaks down rocks?
Plant roots grown into fractures and wedge apart the rocks as the plant grows; burrowing animals move material to the surface for weathering processes; decaying organisms produce acids which break down rocks, and human activities like mining and paving for road construction.
How do rocks change during metamorphism?
Describe how a rock may change during metamorphism. When rocks are subjected to elevated temperatures & pressures they can change form in the mineralogy, texture, and, sometimes, chemical composition. Explain what is meant by the statement "every metamorphic rock has a parent rock.".
How do evaporites form?
Evaporites form from crystals that precipitate during evaporation of water (water with dissolved material in it), such as in a drying lake bed. Rock gypsum and rock salt are two evaporites. Describe two processes by which sediments are transformed into sedimentary rocks.