Classification of Metamorphic Rock.
biotite, muscovite). 3 types of rocks There are 3 types of rocks found on Earth: Igneous Sedimentary Metamorphic.
Descriptions should be reasonably comprehensive but clear and succinct, typically no more than two or three sentences.
After Bard (1986) Microtextures of Igneous and Metamorphic Rocks.
-Texture and mineral content of metamorphic rocks depend on:-Parent rock composition: a).
Analysis of Deformed Rocks Figure 23 -45. Ex: Quartzite - formed from sandstone.
Metamorphic rocks DATHAN C S. 2.
Igneous Rock Igneous rock-Forms when magma cools within earth.-High temp allows magma to cool slowly.-Slow cooling allows time for LARGE mineral crystals to form.-Examples: Granite, Diorite, Gabbro. Metamorphic Rocks and Minerals •Sometimes rock are subject to pressure and heat but do not melt.
The protolith is subjected to heat (greater than 150 degrees Celsius) and/or extreme pressure causing profound physical and/or chemical change.
Compaction: The weight of overlying sediments forces the sediment grains closer together.
Textures of metamorphic rocks • Excess energy present in deformed crystals (elastic), twins, surface free energy • Growth of new grains leads to decreasing free energy -release elastic energy, reduce surface to volume ratio (increase grains size, exception occurs in zones of intense shearing where a number of nuclei are formed).
Graphical analysis of the relationships between deformation (D), metamorphism (M), mineral growth, and textures in the rock illustrated in Fig ure 23 -44.
Foliation is a planar fabric that cuts through the rock.
Metamorphic rocks and processes • Metamorphism comes from the Greek words "Meta" - change "Morphe" - form • Metamorphic rocks form by solid-state (no melting) transformation of preexisting rock by processes that take place beneath Earth's surface.
Metamorphic- crystalline-forms as rocks are .
These criteria are not mutually exclusive and . Comic Sans MS Times New Roman Notepad Regular Helvetica Marker Felt Blank Presentation PowerPoint Presentation PowerPoint Presentation PowerPoint Presentation PowerPoint Presentation PowerPoint Presentation PowerPoint Presentation . Metamorphic rock:- The rocks which have formed by various types of metamorphic processes on the pre-existing igneous and . • Heat, pressure, & chemical reactions alter mineral content, texture (size, shape, & distribution .
• Minerals are most stable in the environment they formed.
Oxford . View: 285.
3 types of rocks.
Each of these will be discussed in turn, then we will summarize how metamorphic rocks are classified.
IMPORTANT: A metamorphic facies is not a single rock-type but a wide range of minerals that form under similar P-T and fluid composition conditions.
Kinds of Metamorphism 1) Thermal metamorphism (Contact metamorphism) • Heat is dominant factor due to - Increase in depth - Intrusion of magma. Introduction to Petrography -- John Butler, University of Houston; on-line course materials for igneous, sedimentary and metamorphic petrography. resulting metamorphic rock will have similar composition to parent rock
They are classified by the way in which they form. Spry A.
If metamorphic rocks retain relicts of the initial rock texture, the texture receives the name of the primary texture with the prefix "blasto-," for example, blastoporphyritic and blastopsammitic. An aggregate of one or more minerals; or a body of undifferentiated mineral matter (e.g., obsidian); or of solid organic matter (e.g., coal) More than one crystal. Classification of metamorphic rocks is based on mineral assemblage, texture, protolith, and bulk chemical composition of the rock.
To The Point Powerpoints and Lessons.
Rock Texture The texture of a rock is defined by observing two criteria:1) grain sizes,2) grain shapes.
Evolotion of metamorphic belts.
2. Winter (2001) An Introduction to Igneous and Metamorphic Petrology. Metamorphic Rocks "If something is gneiss, don't take it for granite." Metamorphic Agents Pressure (>1,000 times atmospheric pressure) Temperature (>300 degrees C) Chemical Fluids (mineral saturated hot water) Metamorphic Environments Contact (thermal) - intrusion by magma Hydrothermal - ion-rich hot water circulates through cracks Mountain Building - regional metamorphism .
Journal of Petrology, 2, 277-311. • Explain how magmas produce a variety of igneous rocks with textures that vary according to the environment of their formation. • Recognize the different types of metamorphism, the processes that cause them, and the environments in which they occur. petrogenetic principles of metamorphic rocks.] The foliated rocks like slate, gneiss and schist are used as roofing material tabletops, staircases, etc.
Is a branch of geology, which deals with study of rocks (Petro=rock, Logos=study) ROCKS IGNEOUS -most abundant -primary rocks -source is magma or lava SEDIMENTARY -thin veener above the Sial and Sima in Oceanic and Continental Crusts -secondary rocks METAMORPHIC -proportion is similar to that of Igneous rocks -change of forms of Ig. 6.3: Metamorphic Textures. Give an example for a rock with cataclastic structure.
Mineral composition forms the basis for naming nonfoliated metamorphic rocks. Directed pressure results in the formation and alignment of flat (platey) minerals such as micas (e.g.
Journal of Petrology, 2, 277-311.
Extrusive .
Textures in a hypothetical andalusite porphyryoblast-mica schist. Metamorphic rocks form by recrystallization in the solid state because of changes in temperature, pressure, or the composition of pore fluids. Classification of Metamorphic Rocks • Based on texture and index minerals • Foliated Textures . Metamorphic Rocks Dr. David Steer Rock Cycle Metamorphic Rocks Change in composition and/or texture of a rock Occurs as the result of increasing pressure and/or temperature.
Metamorphism often imparts a foliation upon the new rock. Foliated texture is a pervasive layering caused by compositional layering or by the parallel orientation of platy (e.g, mica) or elongate (e.g., amphibole) mineral grains. (1969). C. Metamorphic Rock Names Field names for metamorphic rocks are less logical, simple, and consistent than names for other rock types. A thorough presentation on characteristics and description of all main types of metamorphic rocks.
Sedimentary texture encompasses three fundamental properties of sedimentary rocks: grain size, grain shape (form, roundness, and surface texture [microrelief] of grains), and fabric (grain packing and orientation).
Figure 23.46. Fabric is a property of grain aggregates.
Analysis of Deformed Rocks. The dark bands are amphibole-rich, the light bands are feldspar-rich.
"Differential stress and/or shear.! • Describe how igneous rocks relate to the two other rock groups (sedimentary and metamorphic). The appropriate metamorphic rock names were used for mafic plutonic rock exhibiting the effects of dynamic metamorphism such that the assemblage consists of secondary hydrous minerals that obliterate the protolith mineralogy . Chapter 3: Igneous Textures • 3.1.1 Rates of nucleation, growth, & diffusion - The relative rates of initial nucleation, crystal growth and diffusion will have considerable influence on the ultimate texture of the resulting rock • However, whichever rate is the slowest will be the overall rate-determining process and exert the most
This power point was used to teach students about the characteristics and types of igneous rocks.
Included topics are how igneous rocks are formed, extrusive and intrusive igneous rocks, crystal size and formation, pictures and examples or igneous rocks. All rocks on Earth are locked into a system of cycling and re-cycling known as the ROCK CYCLE. Knowing the differences between these 3 types of rocks allows us to learn about Earths past.. Igneous Rocks - Formation Igneous Rocks are formed by melting, cooling, and crystallization of other rocks.
Foliation is caused by recrystallization under directed (compressional) stress. Evolotion of metamorphic belts.
Hand specimen descriptions for metamorphic rocks are like those for igneous rocks.
There are two major states of molten rock: Magma and Lava. Download →.
-texture=sizes, shapes and positions of grains in the rocks rocks vs minerals minerals are classified by chemical composition types of rocks the composition of rocks is determined -by the kind of minerals & -the amount minerals that make it up types of rocks 3 types of rocks igneous sedimentary metamorphic formed when magma cools and hardens .
Shelley (1993) Igneous and Metamorphic Rocks Under the Microscope.
Chapman and Hall.
Sedimentary texture encompasses three fundamental properties of sedimentary rocks: grain size, grain shape (form, roundness, and surface texture [microrelief] of grains), and fabric (grain packing and orientation). lecture_07_metamorphic.ppt - Metamorphic Rocks What is a Metamorphic Rock A Metamorphic Rock is a rock that has undergone change from its original form. Metamorphic Textures & Minerals! When directed pressure (or directed stress) acts on a rock, it means the stress on the rock is much greater in one direction than another.
Spry A.
Metamorphic Rocks: Windows into the Earth's Interior Metamorphic rocks form by the alteration of pre-existing rocks in the solid state by heat, pressure, and chemically active fluids.
In general, if the protolith of a metamorphic rock can be determined, the rock is described by adding the prefix meta-to the protolith rock name.
The most important non-foliated rock is marble. Slides: 74 . Miyashiro A. Texture In metamorphic rocks individual minerals may or may not be bounded by crystal faces.
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 Microsoft PowerPoint - Metamorphic Rocks.ppt Author: Earth Science
Metamorphic texture is the description of the shape and orientation of mineral grains in a metamorphic rock.
(1961). Appearance controlled by composition and size and arrangement of aggregate grains (texture) Rocks like crush breccia, mylonite and slate show this type of structure. The size scale used for sedimentary, igneous and metamorphic rocks are different Grain Shape:
The three rock types are: igneous, sedimentary and metamorphic. An Introduction to Metamorphic Rocks "Metamorphic rocks form from other rocks (protolith) by essentially solid-state changes in mineralogy and/or texture as a result of a change in chemical and/or physical environment. It is considered to be an excellent building material for important monumental, historical .
Bedrock Of New York State Identifying Characteristics of Rocks Igneous Intergrown crystals Glassy texture Sedimentary Cemented fragments (sediments) Fossils Organic material Metamorphic Banding Foliated The Rock Cycle BONUS: CLASSIFY this rock as igneous . Metamorphic rocks are one of the three great divisions of all rock types, and so there is a great variety of metamorphic rock types. (1969).
PowerPoint Presentation - Metamorphic Rocks Author: James M. Durbin Last modified by: James M. Durbin Created Date: 7/23/2001 2:18:43 PM Document presentation format: On-screen Show Company: Dept. There can be changes in both texture and mineralogy.
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Metamorphic Rocks Presentation - Free download as Powerpoint Presentation (.ppt / .pptx), PDF File (.pdf), Text File (.txt) or view presentation slides online. 3 types of rocks There are 3 types of rocks found on Earth: Igneous Sedimentary Metamorphic.
Texture In metamorphic rocks individual minerals may or may not be bounded . Figure 23.48a.