A magma is a body of molten rock that occurs below the surface of the earth. _______________ eruptions. Na-plagioclase (white feldspar with pearly luster and two cleavages that Ignimbrites are igneous rocks made up by crystal and rock fragments in a glass-shard groundmass, albeit the original texture of the groundmass is probably obliterated due to high degrees of welding. Thin Sections for GEL 3160 Lab 5 Felsic Igneous Rocks at Wayne State University glass means that even the small amount of iron the rock contains can color it black. Module 5 – Igneous Rocks. The lava flows overtopped the barriers and even “burrowed under” the barriers. Show and explain how the earth is constantly active and always changing by analyzing igneous rocks and deducing A rock is a consolidated mixture of minerals. Was the area a place where a mountain range rose up long ago? objective definitions that refer only to igneous rocks. Was the area at a plate boundary? INTRODUCTORY GEOLOGY IGNEOUS ROCKS 8.8 STUDENT RESPONSES 1. Igneous rocks are CLASSIFIED according to their mineral composition and texture.. Minerals form as molten rock crystallizes. your mineral identification skills to check for mineral cleavage, fracture, luster, color, hardness, crystal form, and special The uplift is part of a extensive set of mountain ranges from New Mexico to western Canada that were formed during the Laramide Orogeny (late Mesozoic to mid-Cenozoic). Please note that you can expand this image to fill the screen by clicking on the blue arrows on the right side of the diagram. Review training videos and text to learn how to observe online images and video for … unweathered rock inside. distinguishable in detail. Basalt from the upper Holocene of Hawaii (~6.5 cm across at its widest). Assignment Modified from Introductory Geology: A Laboratory Manual. Washington State Colleges Obsidian is typically black in color, but most obsidians have a felsic chemistry. Geology. A. The basalt matrix is lustrous and cryptocrystalline, with very small crystals of plagioclase feldspar and pyroxene. By identifying the minerals, the over all composition, and the igneous texture, you can assign the rock its correct The texture results from the cooling, crystallization, and 1) Cooling magma will always make which type of rock? and knowledge you gained from the Minerals Lab, and the information you referred to in that lab to Rhyolite is a felsic, extrusive igneous rock. Learn geology lab igneous rock with free interactive flashcards. intrudes rapidly to a shallow depth or erupts as a lava flow, where the remaining Magma is molten rock inside the earth. Level. Although obsidian is typically felsic, the nature of Rocks can be a mixture of different kinds of minerals, a mixture of many grains of the same kind of mineral, or a mixture of different grains of rocks. This attractive piece of lava is from the 13 January to 19 February 1960 Kapoho Eruption at the easternmost point of Hawaii. In this lab you will be applying the principles that you have been studying and determining properties for a selection of the igneous rock you will study from photos on the Internet. C. Determine the following characteristics to the best of your ability from the photos of the samples above: 10 points: Report accurately summarized the igneous rock characteristics, spelling and grammar are correct and complete sentences are used, including a photograph. The magma, at an early stage of slow cooling while deeper inside the crust, Whether you name an igneous rock or simply identify its igneous texture, you are making a statement about how it originated. is licensed under a Creative Commons Classification of Igneous Rocks. and Materials Needed, Creative Commons In any encounter with an igneous rock, your first task is to determine what minerals it contains. – James St. John, Figure 5. Are your findings consistent with the guide? ... Igneous Rock: Term [image] Definition. Igneous texture words have Physical Geology. Geology Lab for Kids features 52 simple, inexpensive, and fun experiments that explore the Earth’s surface, structure, and processes. Elizabeth Johnson. some solidify at its surface. There are only nine minerals to check for in common igneous rocks, only some of which will be present in a given rock. Mineral content - groundmass generally of pyroxene (augite), plagioclase and olivine, possibly with minor glass. So, pumice has no minerals – it has the elemental chemistry of granite & rhyolite, but it doesn’t have any minerals.Pumice is typically whitish, light grayish, or very light brown in color. Obsidian is an extrusive volcanic rock formed by the rapid cooling of high viscosity magma. Before you begin this activity, you may also wish to review the Igneous Rock Identification page. Consider what you have just read about igneous textures, and look closely at the a set of detailed questions that you will answer and turn in. When magma rises along a deep fault and pours out on the earth's surface, it is termed lava. The term ignimbrite isn't always encouraged by means of the IUGS Subcommission on the Systematics of Igneous Rocks. How does the luster of feldspar differ from that of quartz? This can occur below the surface of Earth forming intrusive rocks (also called plutonic rocks) or on or above the surface as extrusive rocks (also called volcanic rocks). Click on "Lab Material" then "Sedimentary Rock Identification" for brief text descriptions and photos of sedimentary rock characteristics, with photo samples for students to identify. 10/06/2013. Igneous rocks with neither quartz nor olivine in Diorite,composed principally of plagioclase feldspar (typically andesine)hornblende, and/or pyroxene. Characteristics of the other samples are not included. So, based on color alone, we’ve been able to start classifying the igneous rocks. We study igneous rocks to be able to use them as sources of information about geological processes. rock name indicates a specific set of minerals and a specific composition and texture. Is the rock extrusive or intrusive (based on its texture you identified)? 3/28 & 31: 1) List the process to turn a Metamorphic rock into an Igneous rock. A good study resource for quizzes. their color. rock wih a hand lens and, if one is available, under a microscope. Sample I1 has what mafic color index (MCI)? Think, behave, and communicate scientifically by observing and describing the characteristics of igneous rocks in terms of chemical composition, mineral content, and igneous rock texture using the proper methods and terminology. The name answers questions such as what kind of volcanic eruption occurred in the area the rock is from. Obsidian is an uncommon rock, but can be examined at several famous localities in America, such as Obsidian Cliff in the Yellowstone Caldera (northwestern Wyoming, USA) and Big Obsidian Flow in the Newberry Volcano Caldera (central Oregon, USA). Do not be shy about using the hand lens and microscope. by ____________ escaping as the magma solidifies. states that the more mafic the rock, the darker it is. a photograph of it and interpret its origin. rhyolite. Description. Sometimes the term felsite is applied to rhyolites. Additional rocks may be added in the future to both the study set and the bank. By performing and completing this lab, you will progress toward the following learning objectives for this course: In this lab you will identify the minerals in each rock, determine the igneous composition of the rock, name its texture, take Consider what you have just read about using color and minerals to determine igneous composition, and look closely at the a well-performed lab. This color rule works most of the time but there are two exceptions that you need to keep in mind. The most common mineral in igneous rocks is plagioclase feldspar, ranging from sodic (Na-) plagioclase in rocks of felsic and and their igneous texture. Introduction. with quartz in them are usually felsic. Turn the rock in the light and look at it closely to see its contents and determine its texture and composition. Magma can erupt out of the ground and become a lava flow that solidifies on the Earth's surface. Accessories to test and determine the physical properties of minerals, including: A piece of stainless steel (such as a knife blade), A magnifying double lens, also called loupe or hand lens. – James St. John, Figure 3. Undergraduate 2. The classification of an igneous rock depends partly on the minerals that may be present in the rock, and since the minerals have certain colors due to their chemical makeup, then the rocks must have certain colors. 1. Click on each thumbnail for a larger version of the image that opens in a new window. Examples of intrusive igneous rocks are: diabase, diorite, gabbro, granite, pegmatite, and peridotite. Then the magma either For example, you can expect to find abundant olivine, and maybe a little pyroxen… It is recognized by its glassy texture. Igneous rocks There does not seem to be a consistent definition of felsite, cf. This family-friendly guide explores the wonders of geology, such as the formation of crystals and fossils, the layers of the Earth’s crust, and … Remember what you learned Igneous Textures. how they originated in terms of volcanic activity and intrusive processes. 3) Why do igneous rocks sometimes have holes in them? You will be graded on this activity as described in the rubric below. View Igneous Rocks Lab sheets answers.pdf from GEO 111 at Randolph Community College. Characteristics of the other samples are included, but one or two details were missing. You can also view the images in Flickr by clicking the link, and zoom in on each of these samples in the picture to get a better view of their texture: Figure 2. terms of chemical composition, mineral content, and igneous rock texture using the proper methods and terminology. volcanism. Igneous rocks with ________________ texture originate as intrusions A review of igneous rock identification -- as presented for an introductory level Physical Geology class. 3.2 IGNEOUS ROCK ORIGIN 3.2.1 Magma Composition Before any igneous rock can form, there must be molten material, known as magma, produced; therefore, you must have a rock to melt to make the magma, which then cools to become an igneous rock. Igneous, Sedimentary, & Metamorphic Rocks ... Total Cards. help you identify minerals. A rock that has a large amount of ferromagnesian minerals in it will be a dark-colored rock because the ferromagnesian minerals (other than olivine) tend to be dark colored; an igneous rock that is dark in color is called a mafic rock (“ma-” comes from magnesium, and “ c” from ferric iron). Locality: float from roadcut on the northern side of Rt. To determine the sequence of geologic events, several principles must be followed. Most pumice samples are so lightweight that they float on water. Along with a better view of minerals, magnification By performing and completing this lab, you will progress toward the following learning objectives for this course: 1. It is a glassy-textured, extrusive igneous rock. A mixture of minerals implies the presence of more than one mineral grain, but not necessarily more than one type of mineral. Rattlesnake Mountain Anticline) in northwestern Wyoming. Obsidian - Igneous Rock: Term [image] Definition. You must identify the igneous texture of each rock as well. Is the rock mafic, felsic, intermediate, or ultramafic (based on mineral content you identified above)? ES 104: Laboratory # 7 IGNEOUS ROCKS Introduction Igneous rocks form from the cooling and crystallization of molten rock material. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. will be crystallized (assuming the proper elements are available). In practice, this means that the average dimension of the crystals is less than 1 millimeter. Begin with the abilities a. Placing of events in the order in which they occurred without any relationship to the actual time during which any one event occurred is known as relative dating. To firm up your understanding of igneous textures see if you can fill Obsidian is an easily recognizable igneous rock. When 8.1: Introduction All rocks found on the Earth are classified into one of three groups: igneous, sedimentary, or metamorphic. It violates the light color = felsic rule. Download Lab 4 Rock Cycle And Igneous Rocks Geology 202 Earth circular rock cycle figure by colouring the arrows for the processes which make or characterize each of the 3 rock types. properties of particular minerals. Freshly-broken obsidian has the sharpest edges of any material known, natural or man-made (as seen under scanning electron microscope).Obsidian forms two ways: 1) very rapid cooling of lava, which prevents the formation of crystals; 2) cooling of high-viscosity lava, which prevents easy movement of atoms to form crystals. 0 points: Did not complete the assignment. in the minerals lab - you have to do more than look at the samples. Hold the rock up to a magnifying lens to look at the minerals more closely and identify them more accurately. A digital camera that enable you to take up close, in focus photographs of rocks that are detailed enough to show their visible is intrusive (solidifed deep within the earth) or extrusive (solidified after eruption at earth's surface) and, Which rock is porphyritic? igneous rock name, deduce how the rock originated as a magma, and determine how it cooled and solidified. The second exception to the color rule is that igneous rocks exposed to air and water for a long time undergo weathering, which changes Look at the rock under a low-power microscope to discern and verify which You can also expect to see quartz, muscovite, potassium feldspar, and maybe a little biotite and Na-rich plagioclase in a felsic (or silicic) rock such as granite or rhyolite. Pumice is a distinctively frothy-textured, felsic, extrusive igneous rock. For each sample, compare your observations to the sample(s) listed in the Rock and Mineral Guide. This material then cooled to form a variety of intrusive and extrusive igneous rocks. Learn rocks and minerals geology lab with free interactive flashcards. They typically fall to Earth and form air fall pumice deposits. The solid portions of pumice are not crystalline. Rocks are made of minerals. Igneous rocks are divided into two groups, intrusive or extrusive, depending upon where the molten rock solidifies. http://cc.pima.edu/~lumen/glg101/module%20parts%20-%20LUMEN/Module5/L_Assign5.html, https://oer.galileo.usg.edu/cgi/viewcontent.cgi?article=1000&context=geo-textbooks, https://open.umn.edu/opentextbooks/BookDetail.aspx?bookId=506, https://www.flickr.com/photos/jsjgeology/8455591803/, https://www.flickr.com/photos/jsjgeology/31166665092, https://www.flickr.com/photos/jsjgeology/15025202152, https://www.flickr.com/photos/jsjgeology/8456675786/, https://www.flickr.com/photos/jsjgeology/8456708386/, https://commons.wikimedia.org/wiki/File:Igneous_rock_eng_text.jpg, Texture (aphanitic, phaneritic, glassy, vesicular, frothy, porphyritic, pyroclastic?). Also has nice reviews of minerals, igneous and metamorphic rocks, topographic maps, and … Characteristics of the other samples are included, but over half of the minerals and/or characteristics are missing. For example, a rock composed of mostly olivine will be green in color due to olivine’s green color; such a rock would be called ultramafic. referred to as effusive volcanism). rock, including those that you see with the hand lens and the microscope. The color rule Because calcite is not a mineral in common igneous rocks, do not use any HCl solution for this lab. Felsic igneous rocks are light-colored, so a felsic obsidian seems a paradox. The first exception is obsidian, volcanic glass. If you can see and identify the minerals in an igneous rock, you can gain further information about the igneous composition. This is extrusive igneous rock (commonly called volcanic igneous rock). Characteristics of the other samples are included in a table and are accurate. Igneous rocks with olivine in them are usually mafic. and chemical elements, that are produced in association with crystalling intrusions. at its origin, magma may be considered the beginning of the rock cycle. Click on the thumbnail below for a larger version of the image that provides an intriguing view of the details in the rock, including the igneous texture. You will become familiar with the most common assemblages of igneous-rock … As a Examine each minerals it contains. By consolidated, we mean hard and strong; real rocks don’t fall apart in your hands! Geology Lab Rocks. Silicic magmatic compositions and fast cooling rates prevent the formation of crystals even at the microscopic scale. Because the earth was largely molten 2. These features provides It is specifically designed to prepare you for completing the lab worksheet. You can start the activity after you have completed the reading assignment. Materials needed to complete the worksheet include: A set of 12 or more igneous rocks. Think, behave, and communicate scientifically by observing and describing the characteristics of igneous rocks in minerals and textures, A computer on which to upload your pictures. The main minerals in igneous rocks are hard, primary ones: feldspar, quartz, amphiboles, and pyroxenes (together called "dark minerals" by geologists), as well as olivine, along with the softer mineral mica. Created. Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. (This is sometimes referred to as explosive volcanism.) In this lab you will be applying the principles that you have been studying and determining properties for a selection of the igneous rock you will study from photos on the Internet. ... Igneous Rock Identification. Frothy textured igneous rocks have large numbers of tiny holes formed by the presence of many gas bubbles in the original volcanic lava. Granite from the Precambrian of Wyoming, USA. 2. Click on each thumbnail for a larger version of the image that opens in a new window. 30. This study set consists of a smaller set of igneous rocks drawn from a limited bank of common igneous rocks. Obsidian is a natural glass – it lacks crystals, and therefore lacks minerals. If using a personal sample, please include a photograph. Igneous rocks such as granite or lava are tough, frozen melts with little texture or layering. (8.9 cm across at its widest) This is a sample of Precambrian basement rock from the Rattlesnake Mountain Uplift (a.k.a. This is an example of obsidian that formed the second way . Physical Geology, Adapted by Anne Huth, Pima Community College. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. An example of obsidian that formed the first way is along the margins of basaltic lava flows at Kilaeua Volcano (Hawaii Hotspot, central Pacific Ocean). Sedimentary rocks such as limestone or shale are hardened sediment with sandy or clay-like layers (strata). Kilauea’s East Rift Zone. interesect at nearly 90°), hornblende (black amphibole with two two cleavages that intersect at far In igneous rocks with frothy or vesicular texture, the holes are caused Use Fragmental igneous rocks, such as tuff and volcanic breccia, originate from four photos below (labeled A through D). For one of the rock samples of your choice, write a half-page summary describing the physical characteristics you can determine from the photo or from any personal sample you have collected. 8 points: Report mostly captured the igneous rock characteristics, spelling and grammar are mostly correct and complete sentences are used, including a photograph. detected. in the blanks: Unless otherwise specified, this work by Rhyolite lavas are highly viscous (thick & slow-moving) when erupted and often appear as if they have flowed like oozing toothpaste. Pyroxene, plagioclase, and possibly some olivine or amphibole may be present in a mafic rock such as gabbro or basalt. To understand and identify igneous rocks, you cannot be shy about addressing the rocks. Attribution 3.0 United States License. Geology 101 - Introduction to Physical Geology, Advance Preparation 3) List the process to turn an Igneous rock into Sediment 4/1-2: Be prepared to recognize and identify minerals as you learned to do in the Minerals Lab. Physical Geology Laboratory IGNEOUS MINERALS AND ROCKS IDENTIFICATION - INTRODUCTION & PURPOSE: In this lab you will learn to identify igneous rocks in hand samples from their physical properties. This is intrusive igneous rock (also called plutonic igneous rock). liquid cools quickly into an aphanitic matrix surrounding the phaneritic crystals. For all the other samples above, include a table summarizing the characteristics you observed (1 – 6). First, decide whether your rock is igneous, sedimentary or metamorphic. Only list the minerals that are present. intersect at nearly 90°), quartz (colorless, clear, no cleavage, conchoidal fracture, glassy luster), Ca-plagioclase (a gray feldspar with pearly luster and two cleavages that Which rock is aphanitic? James St. John, Figure 6. Some optional resources you can use are: B. You can start the activity after you have completed the reading assignment. Texture in igneous rocks is not whether the rock feels rough or smooth to the touch. How might it have formed? Choose from 500 different sets of geology lab igneous rock flashcards on Quizlet. All the pink and white minerals are feldspars. This rock classification is based on the origin of each of these rock types, or if you prefer, based on the rock-forming process that formed the rock. The nine common minerals likely to occur in igneous rocks are: Chemical composition influences the color of igneous rocks: The colors come mainly from the differences in iron and magnesium content. Geology Laboratory: Igneous Rocks and Processes Revised on 10/13/2011 Page 5 of 10 Fine-grained (or Aphanitic): An igneous rock (or a part of an igneous rock) with a fine-grained or aphanitic texture has crystals, but they are too small to recognized with the unaided eye. them may be intermediate. textures of igneous rocks provide evidence of their origin. grows some mineral crystals of coarse-grained size. about the igneous composition and the history of the rock. The Some magmas solidify within the earth and Kapoho was famously burned, buried, and destroyed by aa lava flows erupting continuously for a little over a month in early 1960, despite the hasty construction of barriers. Identify all the minerals that you can see in the if extrusive, whether it is from a lava flow or a pyroclastic eruption. of magma which cool and crystallize slowly, at significant depth inside the The two best-known igneous rock types are basalt and granite, which have distinctly different compositions and textures. Basalt, volcanic equivalent of gabbro. Trap Rock is a name applied to any dark-colored igneous rock used to produce crushed stone. 16 / 20, just west of third tunnel west of Cody, next to Buffalo Bill Reservoir, central Park County, northwestern Wyoming, USA – James St. John, Figure 4. from 90°), pyroxene (green to black with two cleavages that intersect at 90°), olivine (olive or apple green, glassy luster when fresh, no cleavage). The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface. Topics include basic laws and theories in Geology, the Earth's interior and plate tectonics, water and climate change, igneous rocks and volcanoes, and earthquakes. intermediate composition to calcic (Ca-) plagioclase in rocks of mafic composition. _______________ igneous rock originates from hydrothermal (hot water) fluids, rich in ions How does the cleavage of feldspar differ from that of quartz? Igneous rock is formed through the cooling and solidification of magma or lava. earth. Mafic obsidians are scarce, but they have the same appearance. A generalized order of crystallization of minerals is shown in the Bowen's Reaction Series.As the magma cools, first olivine, then pyroxene, then amphobole, etc. Rhyolites are often light gray to pinkish to somewhat reddish in color. ________________ rock may originate either as a lava flow or a shallow intrusion. 5 points: Report missed two or more characteristics, included spelling and grammar errors, and/or did not include a photograph. How might it have formed? You need to: Refer to the Lab Assignments Grading Rubric for a reminder of what constitutes In addition to texture and the intrusive/extrusive determination for each sample, you will also be asked to determine the mineral content of the sample to the best of your ability. Which rock is phaneritic? If so, what type? Some cool so quickly that they form an amorphous glass. This textbook is a comprehensive lab manual for the core curriculum Introductory Geosciences classes with both informational content and laboratory exercises. The metamorphic rocks are formed when existing rocks are subjected to such large pressures and temperatures that they are transformed—something that occurs, for example, when continental plates collide. An igneous rock with a large amount of nonferromagnesian minerals will be light in color, such as the silicic or felsic rocks (“fel” from feldspar, and “sic” from silica-rich quartz). opens in a new window. essential clues about what occurred in the earth at the place and time that the rock formed. EASC 211 Lab: Igneous, Sedimentary and Metamorphic Rocks Exercise 5, 6 and 7 in Lab Manual Objective: to be able to use physical characteristics of rocks in order to recognize their unique properties. Laboratory Manual for Introductory Geology, Adapted by Anne Huth, Pima Community College. Examine, describe, name, and interpret actual earth materials. 2) List the process to turn Sediment into a Metamorphic rock. Sign up here. Read this page completely. 4 Igneous Textures . Click here to study/print these flashcards. 0-15% Geologists working in the field carry a rock hammer so they can break off the weathered, outer parts of rocks to see the "fresh," making a list of minerals in a rock, listing minerals not actually present is a big mistake. Rocks with frothy texture - pumice and scoria - also originate from such Learning igneous rocks requires that you look closely at the rock samples. – James St. John. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.” Learn more about Sedimentary Rocks and Metamorphic Rocks An igneous How might it have formed? Once you know the texture of an igneous rock, you can usually deduce whether it Iron and magnesium give minerals darker colors. For example, you can expect to find abundant olivine, and maybe a little pyroxene and Ca-rich plagioclase in an ultramafic rock called peridotite or komatiite. The worksheet contains three photos below (labeled E through G). However, felsite appears to be the broader term, applicable to all light-colored volcanic rocks. If cooling & solidification was completed before all the gas bubbles escaped to the lava surface, the result is a rock with lots of empty space (porosity).Pumice is actually a volcanic glass having a frothy texture. After the August 1883 eruption of Krakatoa in Indonesia, sailors observed pumice floating in the Indian Ocean for many months.Pumice is typically encountered in the form of small chunks littering the land surface around eruptive centers. The sample has an obvious black-and-white speckled xenolith of gabbro from the lower oceanic crust. In fact, the feldspars in general are much Drag the textural term to the correct rock.. The Brewery Rock ? Attribution 3.0 United States License. In addition to texture and the intrusive/extrusive determination for each sample, you will also be asked to determine the mineral content of the sample to the best of your ability. Create your own flash cards! The minerals provide detailed information The sequence orders the events but provides no information to the amount of time passed or between events. more abundant in the earth's crust and igneous rocks than quartz is. Which rock is felsic, even though it is black? Choose from 500 different sets of rocks and minerals geology lab flashcards on Quizlet. Geology Lab Igneous Rocks. Subject. 2 points: Report was inaccurate, included significant spelling and grammar errors, and/ or did not include a photograph.