One of the oldest types of rocks on our planet, metamorphic rocks are mainly formed due to changes in the parameters of temperature and pressure, which act on the parent material. Metamorphic rocks are best identified when looking at the rock as you see them in nature. The type of rock that a metamorphic rock used to be, prior to metamorphism, is called the protolith. This lesson focuses on the properties of metamorphic rocks that help in its identification, most notably characteristics such as banding and foliation. Metamorphic meta to change morph form metamorphic rocks are formed from parent rocks preexisting rocks parent rocks can be igneous, sedimentary, or other metamorphic rocks. A protolith is the original, unmetamorphosed rock from which a given metamorphic rock is formed, e. Knowledge of metamorphic processes and rocks is valuable, because metamorphic minerals and rocks have economic value. The protolith is subjected to heat greater than 150 degrees celsius andor extreme pressure causing profound physical andor chemical change. Ppt engineering properties of igneous rock nebeokike. The result is a profound change in physical properties. It is composed primarily of the mineral calcite caco 3 and usually contains other minerals, such as clay minerals, micas, quartz, pyrite, iron oxides, and graphite.
The modal content of amphibole is larger than 30% vol. As strain increases, the foliation becomes more intense, and the minerals may sort themselves into thicker layers. Identify one metamorphic rock that may be found along the boundary between rock units c and e. Rocks change during metamorphism because the minerals need to be stable under the new temperature and pressure conditions. They are crystalline and often have a squashed foliated or banded texture. Two examples of metamorphic rock descriptions are mediumgrained, hornblendebiotite.
Objective this study aimed to investigate the correlations between the physical and mechanical properties of metamorphic rocks. Igneous rock, also known as volcanic rock, is formed by the cooling of magma or lava. Temperature during metamorphism minerals remain stable at a finite temp range, if that range is exceeded new minerals will result. Although most bedrock aquifers are within sedimentary rock, in some areas igneous or metamorphic rock can be important as aquifers. What are some properties of metamorphic rocks answers. Abstract engineering properties of igneous rocks are the characteristics of the rocks mass. Metamorphic rock identification maine geological survey student sheet purpose.
This requires the ability to observe and recognize these properties. The result is a profound change in physical properties and chemistry of the stone. We are able to do this because the properties do not overlap completely. State the diameter of a particle normally found in rock unit b. Slate is made of finegrained interlocking crystals which lie flat in the same direction, known. Phyllite could also be considered the parent rock as mica schist is a more highly metamorphosed phyllite. Characteristics of metamorphic rocks geology reading. C thermal properties thermal expansion, conductivity, and c in situ stresses. Foliated these have a planar foliation caused by the preferred orientation alignment of minerals and formed under differential stress. Igneous rocks are formed through the crystallization and solidification of magma. Foliated metamorphic rocks pr essure squeezes or elongates the crysta ls. The same metamorphic facies can contain different mineral assemblages as they are a direct product of different mineral and chemical composition of the original rock, i. Metamorphism involves the alteration of existing rocks by either excessive heat and pressure, or through.
The heart of science is the ability to make accurate observations about the natural world. They are characteristically identified by the presence of typical mineral types or assemblages, along with particular accompanying textures. Metamorphism the process through which a rocks structure is changed by heat and pressure. Rocks are identified by making a series of decisions about their properties, such as texture, composition, hardness, etc. Metamorphic rock may be formed when magma is injected into the surrounding solid rock, as shown in fig. They can be divided into many categories, but they are typically split into. This type of rock is classified by cooling time and the type of magma it is formed from. You will also identify some igneous rocks which give rise to certain metamorphic counterparts. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineralrich fluids or, more commonly, some combination of these factors.
A new approach for estimation of properties of metamorphic. Metamorphic rocks can be formed from sedimentary, igneous and even other metamorphic rocks. Metamorphic rocks are rocks that have undergone a change in texture andor. The key to common metamorphic rocks allows someone to identify a rock based on its properties. In this first part of the activity, you will identify a number of metamorphic rocks that are commonly found in the state of maine. Pdf on jun 1, 2018, zozk abdaqadir and others published physical and mechanical properties of metamorphic rocks find, read and cite all the research you need on researchgate. Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. Atlas of metamorphic minerals university of oxford.
Foliated metamorphic rocks will split along cleavage lines that are parallel to the minerals that make up the. Schist rock properties, formation, occurrence and uses. Arc 1 focuses on learning about rocks and minerals and their properties. Metamorphic rock types there are two major subdivisions of metamorphic rocks. A student found a sample of a solid material that was gray, shiny and made of all the same material. Metamorphic they are formed through the change metamorphosis of igneous and sedimentary rocks. There is also an exploration of the properties of contact metamorphism, a process of baking the rock from nearby intrusions that result in low to midgrade metamorphism. Metamorphic rocks are the third major type of rock, the other two being igneous and sedimentary. Many precious materials, such as marble and many types of gemstones, including diamonds, are formed by the.
Metamorphic rocks pictures of foliated and nonfoliated types. Pdf on jun 1, 2018, zozk abdaqadir and others published physical and mechanical properties of metamorphic rocks find, read and cite all. Metamorphic rocks rocks ks3 chemistry revision bbc. Metamorphic rocks an overview sciencedirect topics. During a rock wall scavenger hunt, students begin to explore rocks in an. Metamorphic rocks were once igneous or sedimentary rocks, but have been changed metamorphosed as a result of intense heat andor pressure within the. Metamorphic rocks metamorphic rocks are formed when rock changes over a period of time due to a lot of physical changes like pressure, heat and different chemical activity. It may be formed simply by being deep beneath the earths surface, subjected to high temperatures and the great pressure of the rock layers above it. A new approach for estimation of properties of metamorphic rocks 115 table 1 rock properties and range of aweighted equivalent sound level values obtained during drilling of metamorphic rocks. A picture gallery of metamorphic rocks including amphibolite, gneiss, hornfels. These properties make it useful for a wide variety of architectural, practical, and. Specific heats for rocks can be obtained from data on rock forming minerals. Mica schist, the most common schistose rock and the second most common metamorphic rock, is composed mostly of mica usually biotite or muscovite and smaller amounts of quartz. Mineral composition controls such properties as hardness, density, and solu, bill.
Pdf physical and mechanical properties of metamorphic rocks. Metamorphic rocks are those formed by other types of rocks that have been exposed to heat, pressure and time, which change them into a different type of rock. Distinguish between foliated and nonfoliated metamorphic rocks. Therefore, one of the things students must learn is how to make systematic observations, and then logically use those observations to classify things. The presence of mineral layers, called foliation, is an important feature for classifying metamorphic rocks. Metamorphic rocks metamorphic rocks are the result of the transformation of a preexisting rock type, the protolith, in a process called metamorphism, which means change in form. Physical geology metamorphic rocks flashcards quizlet. Ii origin, texture, and classification of metamorphic rocks teklewold ayalew encyclopedia of life support systems eolss as on the properties of the country rock.
Characteristics of metamorphic rocks science struck. The word metamorphism comes from ancient greek words for change meta and form morph. Department of transportation federal highway administration. For the purpose of rock mass classification, the use of the well known point load strength index can be useful as the. Read this sciencestruck article to gain extensive information about the main. Metamorphic rocks and processes metamorphism comes from the greek words meta change morphe form metamorphic rocks form by solidstate no melting transformation of preexisting rock by processes that take place beneath earths surface. The properties of rocks depend upon their mineral composition texture, and struc ture.
A new approach for estimation of properties of metamorphic rocks. Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Identify major minerals contained within a metamorphic rock. The rocks provide clues to their transformation into a metamorphic rocks. When sedimentary rocks or igneous rocks go through the physical process such as pressure exposure, heat changes, and tectonic plate movement at plate edges. Characteristics of metamorphic rock cataclastic metamorphism occurs along with the tectonic plate faults where the rocks get rubbed with each other which results in the grain size reduction. Metamorphic rocks are formed mainly due to changes in pressure and temperature, thereby, transforming the original parent igneous andor sedimentary rocks. They have a significant amount of sheet silicate platy minerals and are classified by composition, grain size, and. Parent rock composition usually no new material added, resulting rock will have similar comp to parent rock. Students will conduct online research, as well as participate in handson activities. The uniaxial compressive strength of a rock material constitutes the highest strength limit of the rock mass of which it forms a part.
Transformation of these rocks are classified as one which could not form non foliated rock and is of low grade. Foliates are composed of large amounts of micas and chlorites. Metamorphic rock, any rock that results from the alteration of preexisting rocks in response to changing conditions, such as variations in temperature, pressure, and mechanical stress, and the addition or subtraction of chemical components. Grade 4 standard 3 unit test a earth materials multiple. They are not made from molten rock rocks that do melt form igneous rocks instead. The composition of the rocks as well as the temperature and amount of pressure placed on them.
Metamorphic rocks rocks ks3 chemistry revision bbc bitesize. Classification of rocks and description of physical properties of rock introduction uniformity of definitions, descriptors, and identification of rock units is important to maintain continuity in geologic logs, drawings, and reports from a project with multiple drilling sessions, different loggers and mappers. Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineralrich fluids or, more commonly, some combination of these fa. Metamorphic rocks were once igneous or sedimentary rocks, but have been changed metamorphosed as a result of intense heat andor pressure within the earths crust. The charnockite suite or series is a particularly widespread form of granofels. Metamorphic rocks types and properties of metamorphic rocks. Many precious materials, such as marble and many types of gemstones, including diamonds, are formed by the metamorphic process. These rocks are identified by the presence of certain mineral types and specific textures. The foliated rock types that form under these conditions are called schist or gneiss, depending on their texture.
Specific heats for rocks can be obtained from data on rockforming minerals. Rockforming minerals of metamorphic rocks, in thin section a work in progress 1 olivine. An investigation of the properties of rocks and minerals will use samples of multiple different rocks and minerals. Undifferentiated or nonfoliated metamorphic rocks, like coal, often crystallize unevenly due to the impurities in these rocks. Metamorphic rocks are formed by subjecting any rock typesedimentary rock, igneous rock or another older metamorphic rockto different temperature and pressure conditions than those in which the original rock was formed. Read this sciencestruck article to gain extensive information about the main features of these rocks. This process is called metamorphism, meaning to change in form. Texture and structure comprise the fabric in which the individual components of the rock are arranged. It is anticipated that values of these thermal properties of rocks and minerals will be useful for. The two characteristics used to classify metamorphic rocks are foliation and lineation. Metamorphic rocks in nature shale to slate metamorphism deformation of sedimentary rocks metamorphic rocks record how temperature and pressure affected an area when it was forming. Because it has few, if any, readily distinguishable characteristics, you will. Eighth grade lesson metamorphic rocks i betterlesson.
Because of how they are formed, metamorphic rocks constitute a great deal of the bedrock in earths crust. Metamorphic rocks are former igneous, sedimentary or metamorphic rocks that have changed their texture and composition. It is determined in accordance with the standard laboratory procedures. Metamorphic rock identification key pdf version what is pdf. Grade 4 standard 3 unit test a earth materials multiple choice 1. Change is a result of pressure directed stress and heat solid state reaction no net change in chemistry ideally role of groundwater recrystallization of new minerals from old minerals. Relevant vocabulary is also listed on each learning activity page. Metamorphic rock classifications include specific rock types based upon crystal size, diagnostic accessory minerals, mineralogical composition in increasing amounts greater than 15 percent, and structure.
A new approach for estimation of properties of metamorphic rocks 115 table 1 rock properties and range of aweighted equivalent sound level values. The properties of these rocks vary greatly, including their chemical composition, grain structure, texture and color. Origin, texture, and classification of metamorphic rocks. A metamorphic rock used to be some other type of rock, but it was changed inside the earth to become a new type of rock. This second set of lecture notes focuses on physical properties such as weathering potential, slaking potential, swelling potential, hardness, abrasiveness, and other properties such as porosity, density, water content, etc. Their study provides us with important data regarding formation of the earth and the past geological environment. The resulting rocks are generally finegrained and lack attitudinal features.
Foliated metamorphic rocks are arranged in sheets or planes, meaning that the composition of the rocks is relatively uniform and disperses fairly evenly due to pressure. The original parent rock or protolith of mica schist is shale. For example, slate and marble are building materials, garnets are used as gemstones. Bedrock aquifers much of the bedrock is also covered with tens to hundreds of metres of unconsolidated sediments a. Sep 18, 2019 the presence of mineral layers, called foliation, is an important feature for classifying metamorphic rocks. The preexisting rocks may be igneous, sedimentary, or other metamorphic rocks. Rock and mineral identification for engineers november 1991 r u. Physical and mechanical properties of metamorphic rocks. Identify two processes that formed rock unit a from sediment.
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