Q. Why is the texture of a rock important?
Texture plays a very important part in sedimentary rocks, because the petrophysical properties of a rock, hence its porosity and permeability, depend essentially on texture. These components are not necessarily present all together in the same rock.
Q. What is texture in rocks?
The texture of a rock is the size, shape, and arrangement of the grains (for sedimentary rocks) or crystals (for igneous and metamorphic rocks). Also of importance are the rock’s extent of homogeneity (i.e., uniformity of composition throughout) and the degree of isotropy.
Q. Why is analyzing the texture of a rock important for identifying the rock?
Analysis of texture can yield information about the rock’s source material, conditions and environment of deposition (for sedimentary rock) or crystallization and recrystallization (for igneous and metamorphic rock, respectively), and subsequent geologic history and change.
Q. Why do rocks have different textures?
Explanation: The faster the magma cools that smaller the crystals that are formed. Some magma from which the igneous rocks is form come from different combinations of remelted igneous rocks, metamorphic rocks and sedimentary layers. The different sources of the melted material affects the textures of the igneous rocks.
Q. What is the most common characteristic of metamorphic rocks?
Metamorphic rocks were once igneous or sedimentary rocks, but have been changed (metamorphosed) as a result of intense heat and/or pressure within the Earth’s crust. They are crystalline and often have a “squashed” (foliated or banded) texture.
Q. What are the two main categories of metamorphic texture quizlet?
The two major types of texture in metamorphic rocks are foliated rocks, which indicate an alignment of platy minerals; and nonfoliated (granular) rocks, which have no preferred alignment of minerals (may indicate a lack of platy minerals).
Q. What is the texture of schist?
Texture – foliated, foliation on mm to cm scale. Grain size – fine to medium grained; can often see crystals with the naked eye. Hardness – generally hard. Colour – variable – often alternating lighter and darker bands, often shiny.
Q. What is unique about igneous rocks?
Igneous rocks are formed from the solidification of molten rock material. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. Some cool so quickly that they form an amorphous glass. These rocks include: andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff.
