Igneous and metamorphic rocks of the serpentine hot springs. Objectives university of nairobi personal websites. Melting, cooling and hardening turns you into an igneous rock. Metamorphic rocks rocks ks3 chemistry revision bbc. The term facies is an objective description of a rock. All chapters of part ii of the book have been rewritten.
Occurrence, texture, and classification of igneous rocks. 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. We know that all three rock types can be turned into metamorphic rocks but all three types can also be changed through the rock cycle. Metamorphic rocks undergo changes in texture, mineralogy, and chemical. The rapid cooling of magma gives a finegrained rock, which may even be glassy, whereas slower cooling gives coarsegrained rock with.
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. How do we classify sedimentary rocks that form from evaporating sea water. Give an example of a divariant metamorphic reaction. Metamorphic and sedimentary 18 what process forms igneous. The heat from the primary air is transferred to a small amount of ambient scavenger air 3. Metamorphic rocks form when existing rocks are exposed to heat and pressure deep within the earths surface. 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. The most common textural feature fabric of a metamorphic rock is. An investigation of the properties of rocks and minerals will use samples. Rocks can also be completely melted into magma and become reincarnated as igneous rock. Metamorphic rocks can form when which of the following conditions are met.
Metamorphic rocks are formed from other rocks that are changed because of heat or pressure. 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. They are not made from molten rock rocks that do melt form igneous rocks instead. A are claimed to have certain metaphysical properties, e. Explain why the index minerals used to define an isograd may not occur in rocks of all chemical compositions. Although different rocks can contain the same minerals, they are sorted into different types of rocks depending on how they were formed. Which of the following best describes an igneous rock that. In the diagram to the left go over which rocks are created. Review igneous, sedimentary, and metamorphic rocks and their origins. Igneous rock a is a type of rock that is formed by cooling magma. The different rocktypes are formed, based on cooling history of the magma, its. Extrusive rocks cool rapidly because they have erupted at the earths surface, but intrusive rocks cool more slowly within an insulating blanket of surrounding rocks into which they have been emplaced. Hornblende is a common mineral in both igneous and metamorphic rocks. Explain how metamorphic rocks change into igneous rocks melting and cooling from geo 3004 at university of texas, san antonio.
There is no sign these are the most widespread rock types in the gneiss. Apart from changing themselves, if theres rocks from other types close to them, it is very common that they mix under those circumstances, and eventually give birth to a new type of rock. Water is very important in metamorphic reactions as a participant in many important metamorphic reactions those involving devolatilisation. The formation of sedimentary rocks occurs under what conditions. Metamorphic rocks are former igneous, sedimentary or metamorphic rocks that have changed their texture and composition. Petrogenesis of metamorphic rocks raregeologybookss blog. Discuss the various environments where rocks are created. Metamorphic rocks are very common in the crystalline basement rocks of shields. Ask the students to help you fill in the environments that they think might create the three types of rocks. Primary air is cooled further with direct evaporative cooling.
As per wikipedia, metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. Illustrate how the three different types of rocks can change into another type of rock. Relate common metamorphic rocks to different types of metamorphism. 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. Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means change in form. Learn rocks science metamorphic igneous with free interactive flashcards. Examples of metamorphic rocks are slate and marble. Sedimentary rock forms from the lithification compaction and cementation of. Metamorphic rocks never melt if they did they would become igneous magma. Knowledge of metamorphic processes and rocks is valuable, because metamorphic.
Examples include slate, gneiss, phyllite, and schist. Recommendations by the iugs subcommission on the systematics of metamorphic rocks. Metamorphic rocks are classified by their protolith, which is the parent rock or the original, unmetamorphosed rock, and by texture. Discuss the mode of occurrence and characteristic textures common in metamorphic rocks. Igneous, sedimentary and metamorphic rocks department of. All rocks can be weathered and eroded into sediments, which can then form sedimentary rock. With some parent rock types and under specific environmental conditions, the relative. What is a metamorphic reaction mechnanism and what information can be obtained that is not available from just looking at net reactions. The presence of index minerals in metamorphic rocks allows geologists to assess the temperatures and pressures the parent rock encountered. Experimental investigation of the thermal and mechanical stability of. Metamorphic rocks an overview sciencedirect topics.
Oct 01, 2011 they were metastable all the way down the retrograde path. Also, the chapters introduction and grade have undergone several major changes. Outline the role of volatiles in metamorphic processes. There are three ways that metamorphic rocks can form. This can occur on sedimentary rock, igneous rock or another older metamorphic rock. Once they are exposed to higher temperatures and pressures for a prolonged period of time, the rocks start to change their structure.
Carbon turning to diamonds while under extreme pressure is an example. Below 100 c, no reactions occur except for the evaporation of. Show a picture of the rock cycle bef ore beginning this unit. Changes in heat, pressure, and the chemical environment of rocks can alter mineral compositions and crystalline textures, making them metamorphic metamorphic changes occur in. A brief introduction to metamorphic rocks including a look at how they form as a result of exposure to intense heat andor pressure. They are the most vital and largest groupings of metamorphic rocks. Sedimentary rocks from when weathered particles are cemented andor compacted. Igneous and metamorphic rocks of the serpentine hot springs area, seward peninsula, alaska by travis hudson abstract a composite epizonal stock of biotite granite, herein named the oonatut granite complex, has intruded a diverse suite of metamorphic rocks in the serpentine hot springs area of north.
Metamorphic rocks are those which a are claimed to have certain metaphysical properties, e. This video provides an overview of metamorphic rock formation. As with igneous processes, metamorphic rocks form at different zones of pressure depth and temperature as shown on the pressuretemperature pt diagram. Dec 12, 2017 the rock cycle is a concept of geology that describes the transition of rocks between the three rock types. Which type of rock is formed from cooling molten rock.
Sandstone, conglomerate, shale and fragments of igneous and metamorphic rocks. The original rock is exposed to conditions such as heat or pressure. C have textures due to water and volatile magmatic fluids. 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. Ii occurrence, texture, and classification of igneous rocks gezahegn yirgu encyclopedia of life support systems eolss summary in this article, the manner in which igneous rocks occur in nature is introduced, followed by a discussion of the general textural features and appearance of these rocks. Igneous rocks, sedimentary rocks and metamorphic rocks. Study 50 terms metamorphic rocks flashcards quizlet. Igneous rocks that cool below earths surface are termed. This new edition of petrogenesis of metamorphic rocks has several completely revised chapters and all chapters have updated references and redrawn. Teacher note metamorphic rocks are the most difficu lt to understand and to identify. Origin, texture, and classification of metamorphic rocks. Metamorphic rocks are formed from other types of rocks. A description of how each of the rock types forms and the relationships of the rock types to each. Also my sample schist was likely quite dry as it cooled.
Nonfoliated are formed as a result of tectonic movements or direct pressure which makes their formation highly dependent on their. The pressure experienced by a rock during metamorphism is due primarily to the weight of the overlying rocks i. Unit, because here an older deformational fabric and. The three types of metamorphism are contact, regional, and dynamic metamorphism. Interpreting the different environments where rocks form. In metamorphic rocks facies are groups of minerals called mineral assemblages. Summarize the progression of different rock types produced by regional metamorphism. Primary air stream is sensibly cooled first with indirect evaporative cooling using a one side wet, cross counter flow heat exchanger. Metamorphic and sedimentary rocks form by much slower geological processes over time. Illustrate the time relations between metamorphic minerals and deformation.
Contact metamorphic rocks callegari, e, and pertsev, n n. 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. Six types of rocks of alpine origin were investigated for their suitability. The volcanic cooling effect is relatively shortlived, because the particles settle out of the atmosphere within a few years. Explain how metamorphic rocks change into igneous rocks. Geochronology and isotopic character of ultrahigho. B have different mineral compositions due to increased temperature and pressure. Igneous rocks that cooled on the surface are termed extrusive. 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. This is why we say that the changes are solid state.
Studies of metamorphic rocks provide insights into the physical and chemical changes that take place deep within earth. Products subcommission on the systematics of metamorphic. It takes energy to initiate reactions and in a cooling rock, this tends not to happen. C have textures altered from those originally present by agents such as water and volatile magmatic fluids. 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. Climate change at the end of the cretaceous period the large extraterrestrial impact at the end of the cretaceous period 66 ma ago is thought to have produced a massive amount of dust, which may have remained. The standard scientific notation for pressure is expressed in pascals or megapascals 1 pascal is equivalent to 10 bars. Foliated metamorphic rocks are formed from direct exposure to pressure and heat. Igneous rocks form when molten rock cools and solidifies.
What must happen to a sedimentary rock if it is to turn into an igneous rock. Igneous rocks are formed by the solidification and cooling of magma in volcanic. Choose from 500 different sets of rocks science metamorphic igneous flashcards on quizlet. Foliated metamorphic rocks have four distinguishable types of aligned textures and they normally have a banded or layered appearance. Metamorphic rock is the result of the transformation of a preexisting rock type in a process called metamorphism, which means change in form. Metamorphism can be instantaneous as in the shearing of rocks at plate boundaries or can take millions of years as in the slow cooling of magma buried deep under the surface of the earth. Pressure not only influences the rate and degree of metamorphism, with deeply buried rocks requiring more time and heat to undergo a particular metamorphic processs, pressure also causes textural changes in the rock more later how large the crystals are and their orientations that are so distinctive of metamorphic rocks. B have mineral compositions altered from those originally present by increased temperature and pressure. Arabian gulf region an overview sciencedirect topics. For major rock types from the intermediate unit, the sequence of mineral. The cycle outlines how each rock type can be converted to another rock type through geologic processes. The area surrounding the intrusion where the contact metamorphism effects are present is called the metamorphic aureole.