Learn vocabulary, terms, and more with flashcards, games, and other study tools. Monometamorphism is a metamorphism resulting from one metamorphic event fig. Igneous or sedimentary rocks that have been changed by some combination of heat, pressure, stress, or chemical flux become metamorphic rocks. Metamorphic rocks metamorphic rocks are rocks from sedimentary and igneous origin that have been changed through high pressures and temperatures during orogenesis mountain building or during igneous intrusion contact metamorphism metamorphic rocks cont. Develop a model to describe the cycling of earths materials and the flow. Textures produced by such adjustments range from breccias composed of angular, shattered rock fragments to very finegrained, granulated or powdered rocks with obvious foliation and lineation.
These are formed after transformation of igneous and sedimentary rocks when they are subjected to intense heat and pressure and are influenced chemically by. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot. A process of change 1 metamorphic rock forms from a preexisting rock or protolith. Origin, texture, and classification of metamorphic rocks.
See files on canvas site for this course for the pdf file. See the fact file below for more information on the types of rocks or alternatively, you can download our 20page types of rocks worksheet pack to. Hornfels if clastic shale quartzite if sandstone marble if carbonate 19. Igneous rocks form when rocks are heated to the melting point which forms magma. These stations are igneous, metamorphic, and sedimentary. Metamorphism and metamorphic rocks chapter questions 1. What do most igneous, sedimentary and metamorphic rocks have in common. This is why we say that the changes are solid state. Elements combine chemically to form minerals how does this fit into our understanding of what rocks are.
Products subcommission on the systematics of metamorphic. These include the volcanic haib subgroup and vioolsdrif granite suite along the orange. Hornfels is a finegrained metamorphic rock formed by the action of heat on clay rocks, known as contact metamorphism. High temperature and pressure erases out the fossils of the metamorphic rocks. Knowledge of metamorphic processes and rocks is valuable, because metamorphic. The area surrounding the intrusion where the contact metamorphism effects are present is called the metamorphic aureole. These rocks are most often deduced from single mineral sedimentary rocks. Rocks that change from one type of rock to another kind of rock are called metamorphic rocks. Four common types of foliated metamorphic rocks, listed in order of metamorphic grade or intensity of metamorphism are.
Regional associated with mountain buildings also known as dynamothermal produces both foliated and nonfoliated metamorphic rocks. The texture of a metamorphic rock is both a description of its constituent minerals along with their arrangement and size. Types of rocks igneous sedimentary rocks metamorphic rocks. Pdf file igneous rocks of convergent margins pdf file igneous rocks of the continental lithosphere pdf file pyroclastic rocks. Metamorphic changes do not involve melting higher temperatures are needed for that, nor any change to the chemical composition of the rock. Associated with mountain belts affects very large areas. Appendix b classification of metamorphic and other compositegenesis rocks, including hydrothermally altered, impactmetamorphic, mylonitic, and cataclastic rocks, version 1. Dec 12, 20 metamorphism and metamorphic rocks ppt 1. As a metamorphic rock it is considered of low grade and it can be split into thin pieces very easily. The recrystallization of unmelted material under high temperature and pressure results in aslate bdunite cgneiss dquartzite 3.
As per wikipedia, metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. Keep reading to know more metamorphism is a geological process involving rocks changing their form. Types of rocks igneous sedimentary rocks metamorphic. Objectives university of nairobi personal websites. Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form.
The protolith is subjected to heat greater than 150 degrees celsius andor extreme pressure causing profound physical andor chemical change. Some types of metamorphic rocks, such as quartzite and marble, which also. Metamorphic rocks never melt if they did they would become igneous magma. 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. Thus coarse grained metamorphic rocks involve long times of metamorphism. However, mineral grains like quartz and clay react chemically with each other to form new minerals like mica and garnet and new rock textures. Types of metamorphism pdf file metamorphic rock textures pdf file triangular plots in metamorphic petrology pdf file metamorphic.
Sedimentary rocks do not weather as rapidly as the igneous rocks. Metamorphic rocks have been modified by heat, pressure, and chemical processes, usually while buried deep below earths surface. If there is a serious amount of pressure or heat, these stones undergo metamorphosis, harden and. These rocks are physically deformed and chemically changed due to. If youre not sure what type of rock youre holding, look for clues. Characteristics of igneous rocks most igneous rocks are very hard made of crystals layering is not common in igneous rocks metamorphic rocks sedimentary and igneous rocks can become buried deep in the earths crust. Metamorphism encompasses all solidstate changes in the fabric and composition of a rock body occurring well beneath the surface of the earth, but without the.
Metamorphic rock names have traditionally had their basis in one or more of 4 attributes. Mechanical deformation and chemical recrystallization are the two processes that affect rock during metamorphism. Magma is molten rock, but is not just liquid also contains bits of. When metamorphic rocks form, what main factors dictate the rock that will form. Summarize the progression of different rock types produced by regional metamorphism. Which metamorphic rock will have visible mica crystals and a foliated texture. This new edition of petrogenesis of metamorphic rocks has several completely revised chapters and all chapters have updated references and redrawn. If a rock is foliated, its name is determined by the type of foliation present and the dominant mineralsfor example, a kyanite schist. The parents rock subjected to metamorphismcan be igneous sedimentary or metamorphic rock contact metamorphism an agent lf metamorphism that has high heat in low pressure which created nonfoliated rocks.
The grouping of rocks as igneous, sedimentary, and metamorphic is based primarily upon differences in 1 age 2 origin 3 size 4 hardness 3. Rocks and minerals unit this is a unit i designed for my primarily preschooler, but my older two kids 2nd, 4th grades will join in as well. Foliated metamorphic rocks form under directed pressure pressure that is not the same in all directions or shear stress forces acting parallel to each other, and having the result of smearing the rock. The upper red line is the prograde path, the lower the retrograde. During metamorphism, new minerals grow at the expense of old minerals, andor the shape, size, and arrangement of grains in the rock may change. Studies of metamorphic rocks provide insights into the physical and chemical changes that take place deep within earth. This is how metamorphic got its name as it always starts as a different type of rock, like sedimentary rocks, igneous rocks or even other types of metamorphic rock. The process by which metamorphic rocks are produced is called metamorphism. These sheets require tracing, some matching, and some. Again, thinking about the formation process can help.
Where can i collect landscaping rock on public land. Hornfels are heated when near heat source such as a sill, dike, or. This activity discusses topics related to national science education standards. Metamorphism occurs as a response to changes in the physical or chemical environment of any preexisting rock, such as variations in pressure or temperature, strain, or the infiltration of fluids.
The x axis is temperature in celsius and the y axis is kilometers below the surface. The overall composition of a metasedimentary rock can be used to identify the original sedimentary rock, even. Heat, pressure, and sometimes chemically active fluids and gases can cause parent rocks to become metamorphic rocks. Metamorphic petrology 1 metamorphic processes, contact, regional, t and p variations.
Pdf microstructure of selected metamorphic rock types. The presence of index minerals in metamorphic rocks allows geologists to assess the temperatures and pressures the parent rock encountered. The major types of foliated metamorphic rocks include slate, schist, gneiss, and mylonite. Discuss the mode of occurrence and characteristic textures common in metamorphic rocks. Field description of metamorphic rocks the basic procedural aspects of writing a description for metamorphic rocks or rock units are identical to those for sedimentary rocks and rock units. Relate common metamorphic rocks to different types of metamorphism. Note the strong vertical fabric of the canyon wall.
The original sedimentary or igneous rock is called the parent rock. At what temperature does diagenesis end and metamorphism begin. On the basis of mode of formation the rocks are divided into three categories. Metamorphic rocks changed rocks with heat and pressure but not melted change in the solid state textural changes always mineralogy changes usually. Metamorphic rocks form by solidstate no melting transformation of preexisting rock by processes that take place beneath earths surface. Any unique combination of chemical composition, mineralogy, grain size, texture, or other distinguishing characteristics can describe a rock type.
Contact metamorphism occurs typically around intrusive igneous rocks as a result of the temperature increase caused by the intrusion of magma into cooler country rock. We can measure the mineral compositions and assemblage i. Metamorphism and metamorphic rocks tulane university. Much of our knowledge of the evolution of life on earth derives from fossils preserved in sedimentary rocks. Pressure or temperature can even change previously metamorphosed rocks into new types.
Which metamorphic facies is associated with subduction zones. Igneous rocks are formed by the solidification and cooling of magma in volcanic areas, while. Phyllitic medium to low metamorphic conditions refers to the alignment of platy sheetlike minerals into a layered structure, where the minerals are too small to recognize. These types of metamorphic rocks are found at much shallower depths because the heat from the magma serves as a replacement for the heat generated by intense pressure. Exposure to these extreme conditions has altered the mineralogy, texture, and chemical composition of the rocks. Foliated metamorphic rocks named mainly from their foliation type name foliation type slate slaty texture phyllite schist schistocity gneiss gneissic texture 2. 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. The major types of sedimentary rocks distribution of sediments on the earths surface. Metamorphic rocks form when the buried rock is changed under high temperature and pressure.
Metamorphic rocks are a bit harder to identify because they can share traits with the other rock types. Metamorphic sedimentary igneous metamorphic sedimentary igneous. 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. You can clearly see the deformation and features that are characteristic of an entire area. Metamorphic rocks were once sedimentary, igneous, or another metamorphic rock. Lightcolored dikes and sills of igneous rock cut the metamorphic rocks. Metamorphic rocks are best identified when looking at the rock as you see them in nature. Because igneous rocks form when magma and lava cool, they often have crystals. A rock or a rock complex may bear the effects of more than one metamorphic event e.
Metamorphic rocks are classified by texture and by mineral composition. There is no agreed number of specific types of rocks. This can lead the minerals in them to line up, creating ribbonlike layers called bands. Metamorphic rocks are some of the oldest on earth, are widely exposed in the. Then, the rock was buried underneath subsequent rock and was subjected to high pressures and temperatures, causing the rock to recrystallize. Chemical, mineralogical and structural adjustments of solid rocks to physical and chemical. Metamorphism occurs at higher pressure and temperature than weathering and diagenetic processes. The boundary between metamorphic and sedimentary rocks is generally placed at about 200 or 250c, though deformation is important, too. As for the last of these three foliating types of metamorphic rocks, schist is also a rock that can be broken into thinner pieces due to the great amount of mika contained in it and its well developed foliation. Oct 01, 2011 ive taken a standard diagram of metamorphic facies and drawn on roughly some typical ptt paths. Some sediments and sedimentary rocks are resources in their own right, or contain resources. This planar fabric is characteristic of many metamorphic rocks. Types of rocks and their properties pdf download geography the earths crust is composed of rocks. Recommendations by the iugs subcommission on the systematics of metamorphic rocks.
The bands differ from ore another in colour, texture and mineral composition. Also, the chapters introduction and grade have undergone several major changes. Igneous rocks, sedimentary rocks and metamorphic rocks. Metamorphic rocks are former igneous, sedimentary or metamorphic rocks that have changed their texture and composition. Experiments suggest that the time involved is tens of millions of years. Schist and phyllite rock types are preferentially veryfine to finegrained, showing a strong shape preferred orientation.
Studies of metamorphic rocks provide insights into the physical and. All chapters of part ii of the book have been rewritten. Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. They are distinguished by their textures and secondarily by their compositions. Outline the role of volatiles in metamorphic processes.
Different rocks reach different peak temperatures, varying from lower grade greenschist rocks up to granulite facies gneisses. Types of rocks and their properties pdf download geography. Rocks are formed on earth as igneous, sedimentary, or metamorphic rocks. Igneous rocks are formed deep within the earth and are formed by heat. A metamorphic rock bsedimentary rock cigneous rock dvolcanic rock 2. Rocks are aggregates of different minerals silicate minerals. Selection file type icon file name description size revision time user. Sedimentary rocks are formed from the cementing together of sediments, or from the compaction squeezing together of sediments, or from the recrystallization of. 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.
Metamorphic rocks are igneous, sedimentary, or other metamorphic rocks whose texture and composition has been changed by metamorphism. Metamorphic petrology 2 metamorphic facies heat flow and heat production in crust. Where does water in hydrothermal chemically active fluids come from. It has a nonfoliated metamorphic rock that has no specific composition. Rocks and minerals scavenger hunt aboriginal access to. Metamorphic textures and structures geology universe. In geology, metasedimentary rock is a type of metamorphic rock. Metamorphic rocks are formed when other types of rocks change because of the enormous pressure and heat they experience deep within the earth.
Since new minerals are created during metamorphism, the end product metamorphic. Metamorphism involves changes in mineral assemblage and rock texture and occurs in the solid state as a result of changes in temperature and pressure. The following is a list of rock types recognized by geologists. Physical geology metamorphic rocks flashcards quizlet. Metamorphic rock names field names for metamorphic rocks are less logical, simple, and consistent than names for other rock types.
Main types of metamorphism regional metamorphism is a type of metamorphism which occu rs over an area of wide extent, that is, affecting a large rock vo lume, and is associated with largescale tectonic processes, such. Contact metamorphic rocks callegari, e, and pertsev, n n. Changes occur in the solid state because melting doesn t occur. Chemical, mineralogical and structural adjustments of solid rocks to physical and chemical changes at depths below the region of sedimentation. Igneous, sedimentary and metamorphic rocks the building blocks of landforms rocks we have now seen the relationship between elements and minerals. The rocks which do not have planar patterns of strain or stretching are termed as nonfoliated metamorphic rocks. Metamorphic rocks pictures of foliated and nonfoliated types. Such a rock was first formed through the deposition and solidification of sediment. Phsysical geology, metamorphic rocks union college. Metamorphism and metamorphic rocks chapter questions. Metamorphism and metamorphic rocks rocks created by heat, pressure andor chemically reactive fluids metamorphic rocks are produced from igneous rocks sedimentary rocks other metamorphic rocks 2. Dynamic metamorphism, or cataclasis, results mainly from mechanical deformation with little longterm temperature change. The original rock is subjected to heat with temperatures greater than 150 to 200c and pressure around 1500 bars, causing profound physical andor chemical change.
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