Rocks are basically classified into igneous, sedimentary, and metamorphic rocks. Feb 17, 2016 the banded rocks in the cliffs beyond the mountain hut were originally lavas and sediments formed in the sea. The nomenclature of metamorphic rocks is classified according to various criteria, especially texture, composition, and pt conditions of metamorphism. Thermal metamorphic rocks are not as common or plentiful as regional metamorphic rocks. Notice the platy layers that run from left to right within the rock. Origin, texture, and classification of metamorphic rocks. Rocks and minerals unit the science zonewhere everyones. If the schist is exposed to even higher temperature and pressure, it will become gneiss a different kind of gneiss than the granitic gneiss because slate is its.
They are notoriously difficult to photograph and the collection gathered here represents the finest ever assembled. A rock is a solid cumulative of minerals located in the earths lithosphere. Atlas of metamorphic rocks detailed field and hand specimen photographs of metamorphic rocks grouped by setting and composition regionallow. In some cases gneisses are produced by higher grade metamorphism than schists. Metamorphic rocks form at higher temperatures and pressures than sedimentary rocks.
Elements combine chemically to form minerals how does this fit into our understanding of what rocks are. Kendall this elegant book fits nicely in ones hand and is beautifully reproduced. A color atlas of rocks and minerals in thin section edited by w. Deep drilling in the stable platform shows that the bulk of the continental crust is also made up of metamorphic rocks. This sciencestruck writeup lists a few facts about the composition of these rocks. Metamorphic rocks qfiles the online library of knowledge.
If a rock is foliated, its name is determined by the type of foliation present and the dominant mineralsfor example, a kyanite schist. Metamorphic rocks are formed when rocks are subjected to such great pressure and heat that their mineral composition is altered. If you know the name of a rock and want to learn more about it, clicking on the name will take you to a picture and a description. Polymetamorphism article about polymetamorphism by the free. Name the rock material is given according to the geological classification based on mineral content, texture, mineral size and origin sedimentary, igneous. The list of counties below link to pdf files of corresponding county rocktype maps. Metamorphic rocks produced in this subduction zone include serpentinites, greenschists, and amphibolites. Buy atlas of metamorphic rocks and their textures on free shipping on qualified orders. Metamorphic rocks make up a large part of the continental crust. Nov 03, 2016 this website and its content is subject to our terms and conditions. The process by which metamorphic rocks are produced is called metamorphism.
Examples from cornwall that show the first tectonic and metamorphic fabrics in metasediments, plus a variety of sedimentary and igneous rock types in outcrop and hand. Sometimes a metamorphic rock can become metamorphosed. Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. Characteristics 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. In the present lecture, we shall go through another, but equally important class of rocks metamorphic rocks that are formed when sedimentary or igneous rocks are subjected to heat and pressure. Most metamorphic rocks have the same overall chemistry as the parent rock from which they formed this chemistry determines how the rock will change during metamorphism.
An example of this type of thermal metamorphic rock is marble, which is actually limestone whose calcite has recrystallized. Each county map has been scaled to fit on lettersize paper. Rockforming minerals of metamorphic rocks, in thin section a work in progress atlas of metamorphic minerals. These sheets require tracing, some matching, and some cuttingpasting activities. Oct 27, 2006 metamorphic rocks are rocks that have undergone metamorphism, or change in form. Brady jb 1977 metasomatic zones in metamorphic rocks. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Metamorphic rocks metamorphic rocks rocks that have been subjected to either enough heat or pressure to cause the minerals in that rock to undergo solid state chemical changes. A link within the document will lead you to a pdf file geared for printing this list. Metamorphic rocks are rocks that have undergone metamorphism, or change in form.
Igneous, sedimentary and metamorphic rocks science struck. How old are these rocks anzaborrego desert paleontology. If the temperature of metamorphism is high enough for partial melting of the rock to occur, the changes would still be called metamorphism until the melt is separated from its. Metamorphic rocks form at lower temperatures than igneous rocks. Illustrate how the three different types of rocks can change into another type of rock. Metamorphic rocks are classified on the basis of texture. This is why we say that the changes are solid state. Amphibolite, marble, and quartzite are defined according to their composition. For example, if slate is exposed to higher temperature and pressure, it will become a rock called schist. Sponsored by the national audubon society, the national wildlife federation, and the roger tory peterson institute. The protolith can be igneous or sedimentary rock, or just some older metamorhpic rock.
If the minerals are segregated into alternating light. New minerals form that are in equilibrium with the new environment, and a new rock texture develops in response to the growth of new minerals. Metamorphic rocks form when igneous or sedimentary rocks are buried deep in the earth, compressed, and held for long periods of time at high temperatures. It looks as though you could easily break off layers from the front surface of the outcrop. Metamorphic rocks are the most difficu lt to understand and to identify. What this means is that a preexisting rock type, the protolith, is exposed to heat greater than 150 c. Jan 04, 2016 types of metamorphism, texture, structure of metamorphic rocks slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising.
Bthe reduction potential of this couple can be determined by measuring the electromotive force generated by a sample halfcell connected to a standard reference halfcell figure 20. Important relationships seen at both macroscopic and microscopic scales include 1 rocks of the shear zone have undergone polymetamorphism, 2 an earlier phase of actinolitic amphibole greenschist facies is replaced in areas by a later phase of hornblendic amphibole amphibolite facies, 3 zones of high strain correlate with rocks with a larger amount of hornblende, and 4 zones of. It looks for different rocks and minerals that were formed under specific conditions. Rock earth materials made up of different kinds of. This means that it has been subjected to more heat and pressure than slate, which is a low grade metamorphic rock. Atlas of metamorphic minerals university of oxford. Pdf a major interest in beryllium minerals, which are rockforming. Igneous rocks, sedimentary rocks and metamorphic rocks.
Rockforming minerals of metamorphic rocks, in thin section a work in progress 1 olivine. The rocks provide clues to their transformation into a metamorphic rocks. When this happens, new minerals may form, and older, preexisting minerals grow and change shape. Show the class a video, or look at books or posters that show weathering, erosion and sedimentary rocks. The foliation is usually perpendicular to the direction of the applied stress. Nonfoliated rocks are given specific names based on their mineralogy and composition. All chapters of part ii of the book have been rewritten. Chemical, mineralogical and structural adjustments of solid rocks to physical and chemical changes at depths below the region of sedimentation. Rock cycle diagram changing of rocks by high temperature and pressure weathering of rocks and sedimentation of porous substance. The banded rocks in the cliffs beyond the mountain hut were originally lavas and sediments formed in the sea. Rocks just beginning to metamorphose are lowgrade metamorphic rocks. Highgrade metamorphic rocks tend to be coarsegrained.
Metamorphic rocks form by recrystallization in the solid state because of changes in temperature, pressure, or the composition of pore fluids. Show a picture of the rock cycle bef ore beginning this unit. Metamorphic rocks are best identified when looking at the rock as you see them in nature. Metamorphic rocks are classified on the basis of texture and composition either mineralogical or chemical may choose some prefixtype modifiers to attach to names if care to stress some important or unusual textural or mineralogical aspects metamorphic rocks.
The best way to tell quartzite from sandstone is to break the rocks. Upper lowgrade to medium grade metamorphism of shale increased size of platy and other minerals minerals clearly visible to naked eye. Introducing the rock cycle by creating a 3d model breaking down the earths crust by erosion sedimentary rocks day 9, 10 andor 11 17. Sandstone will shatter into many individual grains of sand while quartzite will break across the grains. We can measure the mineral compositions and assemblage i. This is a unit i designed for my primarily preschooler, but my older two kids 2nd, 4th grades will join in as well. Sandstone made mostly of quartz fragments recrystallizes into quartzite. Metamorphic rocks never melt if they did they would become igneous magma. This book is a 4 12 x 7 14 paperback with 401 pages.
Some of the interesting things we are going to learn about these rocks are their many and varied textures. Dthe standard reference halfcell consists of an electrode. Metamorphic rocks can be formed from any type of older material. If you continue browsing the site, you agree to the use of cookies on this website.
These can range from textures similar to the original protolith at low grades of metamorphism, to textures that are purely produced during metamorphism and leave the rock with little resemblance to the original protolith. Have student groups examine rocks in their kits and find those. Lecture notes metamorphism introduction metamorphism is a change of form that includes the growth of new minerals, typically in response to a rise in temperature and normally without the involvement of a magma. Like in igneous and sedimentary rocks, there will be some new terms that may be a little bit confusing but these will be adequately explained. Metamorphic rocks in thin section contents image scales widest frame width alsilicates other aluminous minerals amphiboles pyroxenes sheet silicates other metamorphic minerals 20x 6 mm 40x 3 mm 100x 1 mm 200x 0. The rocks within a mountain chain not only sustain considerable pressures but are also heated both generally and by the large scale of intrusion of magma, with the effect that rocks are deformed and recrystallized to varying degrees.
Theres a fill in the blank option for older kids starting on page. Classification of metamorphic rocks based on texturestructures phyllite similar to slate, but slightly coarser phyllosilicate grains grains can be seen in hand specimen, giving silk appearance to cleavage surfaces often cleavage planes less perfectly planar than slates slate strongly cleaved rock cleavage planes are developed due to. Ks3 lesson on metamorphic rocks lower and higher lessons and resources. Igneous rocks are formed by the solidification and cooling of magma in volcanic. Here, the lighter brown rocks in the upper part of the cliff are calcareous schists formed from impure limestones, and the dark rocks below are mainly metamorphosed. Marble, slate, gneiss and quartzite are all examples of metamorphic rocks. They are usually poorly foliated and form at intermediate to high grades of metamorphism of basaltic or gabbroic protoliths. Also, the chapters introduction and grade have undergone several major changes. Tes global ltd is registered in england company no 02017289 with its registered office at 26 red lion square london wc1r 4hq. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience. Metamorphic rocks are classified by texture and by mineral composition. This rock is therefore half igneous and half metamorphic.
Lowgrade metamorphic rocks tend to be finegrained the newly formed metamorphic mineral grains that is. Below is an alphabetical list of metamorphic rocks. Names that are not linked are ones for which picturesdescriptions are not yet available. The original rocks may be sedimentary, igneous or metamorphic rocks.
Change is a result of pressure directed stress and heat solid state reaction no net change in chemistry ideally role of groundwater recrystallization of. Metamorphic rocks form by solidstate no melting transformation of preexisting rock by processes that take place beneath earths surface. Across 4 a metamorphic rock used for tiles and roofs 5 an organic metamorphic rock 8 limestone is the parent rock of this 10 an agent of metamorphism resulting from the weight of rocks above 11 an agent of metamorphism related to temperature 12 a foliated dense rock that has light and dark colored banding 14 metamorphic rocks having a banded or. Each metamorphic rock can be identified and classified by its composition and texture. This new edition of petrogenesis of metamorphic rocks has several completely revised chapters and all chapters have updated references and redrawn. Polymetamorphism article about polymetamorphism by the. Mohs scale used by geologists to classify a given minerals hardness.
The heat and pressure cause the rocks to metamorphose or change to another form. We have a nice selection of over 50 books to choose from theres something for everyone, from the amateur rockhound to the professional geologist. However, metamorphic rocks can form from metamorphic parent rocks as well. Department of earth and planetary sciences washington. Although metamorphic rocks are forming today, it is difficult to see. The original rock is subjected to heat temperatures greater than 150 to 200 c and pressure 100 megapascals 1,000 bar or more, causing profound physical or chemical change. Nearly all rocks are composed of one or more minerals 6. Texture refers to the physical appearance or character of a rock, such as grain size, shape, and arrangement. The protolith may be a sedimentary, igneous, or existing metamorphic rock.
They are usually poorly foliated and form at intermediate to high grades of metamorphism of. 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. In this lesson you will learn about metamorphic rocks, how they form, and some of their common uses. Igneous, sedimentary and metamorphic rocks the building blocks of landforms rocks we have now seen the relationship between elements and minerals. Metamorphic rocks are those, which have been changed by heat, pressure, fluids, and chemical activity beneath earths surface.
Atlas of metamorphic rocks and their textures pearson. Some minerals in rocks undergoing metamorphism may be transformed into. Cthe sample halfcell consists of an electrode immersed in a solution of 1 m oxidant x and 1 m reductant x. Metamorphic rocks include things like slate, schist, marble and gneiss not the most common of words, but not all that rare, either. Rocks are aggregates of different minerals silicate minerals. Deeper rocks in folded mountains become intermediategrade metamorphic rocks and those deep in the roots of the mountains turn into highgrade metamorphic rocks. Examples from cornwall that show the first tectonic and metamorphic fabrics in metasediments, plus a variety of sedimentary and igneous rock types in outcrop and hand specimen.
With more heat and pressure gneiss will begin to melt. Such rocks shave a parallel arrangement of platy minerals such as the micas. Ii origin, texture, and classification of metamorphic rocks teklewold ayalew encyclopedia of life support systems eolss some metamorphic rocks, particularly those buried to depths of several kilometers, contain numerous veins rich in quartz and feldspar. Objectives university of nairobi personal websites. Metamorphic rocks, those altered by temperature and pressure, display a wide range of textural features under the microscope. Foliated metamorphic rocks have a sheet like or layering orientation of their minerals. An introduction to rocks and minerals with detailed photos, description and identification information. Metamorphic rocks that are classified according to texture include slate, phyllite, schist, and gneiss. The word metamorphism comes from ancient greek words for change meta and form morph. Rock and mineral books learn about rocks and minerals with these great books. Amphibolite these rocks are dark colored rocks with amphibole usually hornblende as their major mineral. Metamorphic rocks are former igneous, sedimentary or metamorphic rocks that have changed their texture and composition. This quiz will help you judge how well you understand the key characteristics of metamorphic rocks with questions about its creation and examples.
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