Lab 6 ESCI 1001 F22

3 NAME: Lily Deutsch Introduction: Part A - A First Pass at Interpreting Sedim You must enter your name above credit for your lab assignmen Lab 6 – Sedimentary Rocks: Gifts o Figure 1. Montage of sedimentary and metamorphic rocks. From right to left: quartzite railroa Michelangelo’s Pieta , carbonate reef, stained glass window, chert tool and a gypsum carving. Combined, sediment and sedimentary rocks only comprise a small fraction (less than 5% Earth’s crust. So why bother with them? Although an insignificant part of the Earth’s volume, sedimentary deposits cover its surfa are the Earth materials people most often encounter. Sedimentary deposits also include e resources from the nearly omnipresent cement and glass of modern cities to fertilizers, fu dietary supplements. Moreover, nearly all our data on past climates or life forms comes fr sedimentary record. In the struggle to work out human impacts on climate and Earth syst sedimentary record is our most crucial archive. Be sure to answer short answer questions with full sentences that briefly expla response and reasoning. Use any number or letter to indicate your choice on multiple-choices questions for '0'. All '0's are automatically graded as errors.

6 Chemical & Biogenic Sedimentary Rock Classification Unlike detrital sedimentary rocks, chemical and biogenic sedimentary rocks are classified composition rather than texture (Table 2). Geologists rely on composition because these r typically form from the in-situ chemical and biogenic precipitation of dissolved ions. Henc of its particles or crystals does not necessarily reflect depositional energy. Large and sma may form in the same area without any transport. Although there is a tendency to disting that formed from chemical precipitation (as when seawater evaporates to form halite, gyp spherical ooids) from rocks that formed from biogenic precipitation (during the growth of shells, or reefs), this distinction has become more blurred as we have begun to recognize microbial organisms in processes we previously considered inorganic.

9 Images courtesy of Siip Sepp via Sandatlas.com Question 1 - A - B Yes - C - D Question 2 - A - B - C Yes - D Question 3 - Arkose Sandstone - Breccia - Chert - Conglo Yes - Lithic Sandstone - Quartz Sandstone - Shale - Siltston Which type of igneous rock was eroded and weathered to produce sand B? - Andesite - Basalt - Diorite - Gabbro Yes - Granite - Rhyolite Four sand samples. Clear grains are quartz, white are plagioclase, salmon-colored are potassium feldspars, and dark colored are biotite or amphibole. Photos are not at the same scale so you cannot compare grain sizes between images. Based on the composition of each sand, which of the four most likely experienced the amount of chemical weathering? Based on their grain shapes, which of these sands most likely underwent the least ph weathering and transport before being deposited as sand? If sand A lithified into a sedimentary rock without any further changes in its composit grain size, what type of rock would it be? (Link to Table 3 of Lab 5 if you need help answering this question.)

12 Question 9 - A - B - C Yes - D - E Question 10 Yes – degree of weathering – different source rocks Question 11 - long distance Yes - short distance Image by Michael C. Rygel via Wik Which of these samples is the most likely to have formed as deposits in a quiet water lagoon or on the bottom of a deep lake? Assuming samples A and C have similar-sized grain, are the differences between the likely due to their degree of weathering or to differences in their source rocks? The rock at left is composed clasts ripped up during a st the storm then transport th long distance before depos or only a short distance?

15 Sedimentary Environments Table 3 lists some of the more common settings of sedimentary rocks. Figure 4. Outcrop at Boom Site with small vertical burrows from marine organisms. Burrows cut across some relict cross-bedding. Cross-bedding and ripple marks can form from either water or wind transport. So how can they formed above or below water? Mud cracks, which form as mud dries out and shrinks volume, suggest exposure as do soil profiles, land animal tracks, or the impression of rain (sometimes preserved on a sand surface). In contrast, if the rock includes fossils of marin organisms or traces of burrows left by marine organisms (Figure 4), it formed underwater. interpreting the origin of sedimentary rocks consider their whole suite of features, from th characteristics of individual rock samples to the sedimentary structures present in field o Sedimentary rocks can form anywhere deposition occurs; from stream and floodplains to swamps, from shoreline beaches to throughout the marine realm. Consequently, sedimen reflect a wide range of environments. While you may not be able to identify the origin of sedimentary rock, most do contain clues to their original setting in their texture, composi sedimentary structures. When possible, consider a sedimentary rock in terms of its outcro well as its hand sample appearance. Often, clues to a sedimentary rock’s origin occur in a rock layers.

18 – pure quartz sands most often form in tropical locations Transition from Sedimentary to Metamorphic Part C. Altering or Metamorphosing Sedim This is the point where Lab 6 moves from considering sedimentary rocks to exploring met rocks. Hence, take a moment to consciously shift gears from one subject to the other, or get terribly confusing. With igneous rocks (Lab 5) we were dealing with rocks that formed from magma. Up to th Lab 6, we have explored rocks that formed from the weathering products (particles and/o other pre-existing rocks. From this point on for the rest of Lab 6, we will explore rocks tha from the alteration of pre-existing rocks due to increased heat and pressure as those rock buried. This difference is important as similar characteristics can mean different things in differen types. As an example, in igneous rocks, crystal size reflects the rock’s cooling history. Lar mean the originating magma cooled slowly, while small crystals indicate a quickly cooling But in detrital sedimentary rocks, grain size instead reflects the energy of the wind or wa currents that deposited the rocks’ original sedimentary particles. Hence, large grains in d sedimentary rocks reflect high energy depositional conditions while small grains reflect lo depositional conditions. Now that we are moving into metamorphic rocks, crystal or grain instead most often reflect higher temperatures and greater pressures during the rock’s metamorphism. Consequently, it is important to consider metamorphic rocks in a differen than sedimentary or igneous rocks. Although metamorphic rocks can form from any type of pre-existing rocks, to make things this lab we will only explore metamorphic rocks that formed from the alteration of sedime rocks. Once sedimentary rocks form, they can be altered. Sedimentary rocks that remain close t Earth’s surface may be exposed, weathered, and eroded to form new deposits. However, sedimentary rocks buried beneath other sediments will metamorphose in response to inc pressures, temperatures, or tectonic stresses. As burial is a gradual process, changes ass with burial typically form a continuum from the compact and cementation of sedimentary to completely transform into new metamorphic rocks. Eventually, it may be impossible to distinguish any trace of the rock’s original sedimentary nature. Changes that significantly sedimentary rock’s original texture or mineral composition fall within the broad field of metamorphism . Although any type of rock may be metamorphosed (even igneous rocks), this lab will only metamorphic rocks that formed from alteration of common sedimentary rocks.

21 Why does Metamorphism Matter? From a more practical viewpoint, metamorphic changes also affect a rock’s possible uses. Using Metamorphic Rocks: Geologists can use metamorphic changes to help unravel the Earth’s past. Different grad metamorphism (and minerals) reflect the stress and temperature a rock encountered, wh help interpret an area’s geologic history. Metamorphic rocks act as geologic ‘thermomete recording the highest temperature and stress that rocks experienced. Although the Minne Valley’s Morton Gneiss now outcrops at the Earth’s surface, its texture and mineral compo reveal it originally formed under very high temperature and pressure conditions, kilomete the Earth’s surface. Erosion and uplift brought this once-deeply-buried rock to the Earth’s When limestone metamorphoses into marble, its recrystallization increases the rock’s phy strength and homogeneity. If stressed, limestone breaks along bedding planes or grain bo In contrast, marble (metamorphosed limestone) is a homogenous crystal mosaic. This ho nature makes it far better suited for use as decorative building stone or in sculptures than limestone. The metamorphism of sandstone to quartzite not only increases the rock’s stre nearly eliminates the rock’s porosity. Water cannot easily move into the rock so quartzite impervious to freeze and thaw cycle damage. This makes quartzite an excellent ballast fo tracks or aggregate for highway construction. Shale (or mudstone) easily breaks down into mud. However, as shale encounters higher temperatures and stress, its clay grains recrystallize, bond, and align with one another. Th resulting rock, slate, is far more durable and easily splits into thin slabs. In past centuries slate’s use in as roofing tiles and classroom blackboards.

22 A summary of common metamorphic rock uses is below. Exercise C – Metamorphosed Sedimentary Ro Question 18 slate’s use in as roofing tiles and classroom blackboards. Metamorphism can create new minerals or drive impurities from a rock. One of our more modern abrasives is garnet, a metamorphic mineral that forms the ‘sand’ used in comme sandpaper. Garnet is a rounded, red mineral that forms as shale and mudstone metamorp beyond the range of slate and phyllite and becomes schist. Anthracite (metamorphosed coal) has fewer impurities than bituminous coal and burns m cleanly to produce fewer pollutants. Unfortunately, while the United States has huge coal we have already exhausted our anthracite deposits. Without new technologies, burning th remaining bituminous coal will generate more airborne pollutants. Note that the processes that alter sediment into sedimentary rock can imperceptibly grad metamorphism as burial continues. Therefore, the transition between sedimentary rock a metamorphosed equivalent is a continuum rather than a sharp boundary. Hence, limeston marble are end members of an unbroken spectrum. Rocks that fall between end member have different names depending on how humans use them. Many rocks that geologists ca ‘limestone’ are ‘marble’ in the construction and interior design businesses. ‘Marble’ has a meaning in those fields as the word has more appeal to consumers who prefer to own ‘m countertops and floors rather than ‘limestone’ ones. The rock at left has the same comp granite. So which feature of the roc it is a metamorphic rock rather tha granite? With this rock having the same com as granite, it is metamorphic and n granite because of the cooling proc

23 What type of metamorphic rock is this? - Anthracite Yes – Gneiss - Marble - Ph - Quartzite - Slate - Schist Images courtesy of Siip Sepp via Sandatlas.com Question 19 (Be sure to choose TWO properties.) – how they break – how heavy they are – how they ta Yes – if they reaction with acid – if they mark paper Yes – how hard th Question 20 (Be sure to choose TWO properties.) – how it breaks – how heavy it is – how it taste granite because of the cooling proc the magma has melted and at whic did. Because of these processes of and their outcome, this rock will be metamorphic whereas if it cooled s would become igneous and consist just minerals. The two rocks shown above are a quartzite and a marble. If you could actually handle samples, which two ways could you use to determine which rock was which? Which two properties of anthracite could you use to quickly and easily distinguish it f bituminous coal?

24 – if it reacts with acid Yes – how shiny it is Yes – its color Using Metamorphic Rocks as Indicators of Past Metamorphic Events So there are two possible scenarios for the shale’s metamorphism: (R-numbers correspond to each sample’s locatio If you had access to a lab, you could also determine that bituminous coal contains mo impurities, including sulfur, than anthracite coal. Hence anthracite is a cleaner burnin While its use does contribute to atmospheric carbon dioxide levels and climate chang not result in acid rain. Unfortunately, most of our remaining coal reserves, especially United States, are bituminous and often contain significant amounts of sulfur. The next five samples represent a line of outcrops from Duluth to St. Cloud (Fig. 8). These formed from the metamorphism of a widespread shale. Two igneous rock masses border t outcrops that were possible sources for the heat that metamorphosed the shale. The St. C Granite to the southwest formed 1.8 billion years ago while the North Shore Volcanic Grou southeast formed about 1.1 billion years ago. Option 1 – A pre-existing shale was intruded and metamorphosed by magma that lat to form the St. Cloud Granite. Option 2 – A shale unit overlying an older granite mass was metamorphosed during volcanism that produced the North Shore Volcanic Group. Figure 8. Location of the five rock samples sim metamorphosed Thompson and Sartell formatio The St. Cloud Granite (1.8 BYA) lies to the south these outcrops while basalts and gabbros of the Shore Volcanic Group (1.1 BYA) lie to the southe Remember that metamorphic rocks ac geologic ‘thermometers’, recording th temperatures a rock experienced. So c what the metamorphic pattern of thes suggests about their origin.

25 Question 21 ( Yes – formation of St. Cloud Granite – volcanism of North Shore Volcanic Group Exercise D –Metamorphic Rocks of Minnesota Was metamorphism more likely due to the formation of the St. Cloud Granite or the v that produced the North Shore Volcanic Group? Figure 9. Water cascading over metamorphic roc Pipestone National Monument. Metamorphosed rocks crop out in the southwestern corner of Minnesota. Most of these ar colored, hard rocks whose relict cross-bedding and ripple marked surfaces attest to their sedimentary origins (Figures 9 & 10). However, a thin blood-red rock layer interrupts this Early native artisans discovered that the red rock was ideal for carving. Pipe heads and fi carved from this stone were traded central North America. Because of the central role tob played in many Indian societies, this rock and its quarry became known as Pipestone. Eve light-colored rock above and below the pipestone layer achieved some fame. To the east Pipestone, near the town of Jeffers, low exposures of that rock emerged from prairie soils outcrop surfaces darkened over centuries of exposure. Indian artists chipped the darkene

26 outcrop surfaces darkened over centuries of exposure. Indian artists chipped the darkene away to create petroglyphs in the hard resistant rock, intricate carvings of images and fig bear mute testimony to the land’s early inhabitants and a vanished way of life (Figure 11) All these rocks owe their origin to an ancient mountain building period that created a sou northeast trending mountain range across central Minnesota and northern Wisconsin. Thi building, called the Penokean Orogeny, lasted from 2.45 to 1.75 billion years ago. Uplift le erosion and from 1.8 to 1.4 billion years ago an expansive system of braided rivers worke way across the region, draining to the southeast. Figure 10. Relict sedimentary structures preserved in metamorphic rocks of Pipestone Nation Monument. On left, well-preserved cross-bedding in vertical rock faces attest to past currents. A ripple marks extend across what was originally a sedimentary bedding surface. Figure 11. Two slabs of petroglyphs from the Jeffers area east of Pipestone National Monument. Figure 12. The ‘pipestone’ layer at Pipesto Monument exposed in a quarry. The pipesto present as a thin layer between thick beds grained metamorphic rock that are not suit

27 Question 22 - Anthracite Yes – Gneiss - Marble - Ph - Quartzite - Slate - Schist Question 23 – as far or further from Equator Yes – closer to the Equator grained metamorphic rock that are not suit carving. Although the pipestone layer was o exposed at the surface, after centuries of q can now only be reached by removing the o harder rock. The rock on the left is similar to the host rock that occurs above and below the ‘pipes layer at Pipestone National Monument. This host rock is coarsely crystalline and harde a knife blade. It also is composed exclusively of one mineral. On the right is a side vie rock similar to the easily carved ‘pipestone’ that formed from metamorphism of what originally a mud layer. Although it is difficult to tell in the image, the rock does not ha natural sheen, so artisans had to polish their carvings by hand. Considering the host rock’s properties and sedimentary structures, what type of meta rock is the host rock at Pipestone National Monument? Based on which types of sedimentary rock were originally present in this area, do you at the time the sedimentary rocks formed Minnesota was as far (or further) from the e than it is now or was it closer to the Equator? (As metamorphism is NOT tied to latitude, you need to consider your answer on the original sedimentary composition and Table 3.)

28 Question 24 – rocks were deeply buried Yes – rocks were only buried to a shallow depth Briefly explain your answer. What feature (of one or both rocks) supports your choice? Question 25 – increased its use because the rock would be more cohesive – increased its use because the rock would be more uniform – decreased its use because the rock would develop foliation Yes – decreased its use because the rock would become too hard to carve Pipestone in the State Capitol? Based on their degree of alteration, do you think the Pipestone area rocks were deepl (highly metamorphosed) or only buried to a shallow depth? I think that the rocks were not deeply buried because of their crystalline features and minerals. This suggests that they needed mineral enriched soil that would not be as f deeply buried because if things kept getting burned we would hit plates. If these rocks had been even more highly metamorphosed, would that have increased decreased the use of the metamorphosed pipestone for carving? For decades, tour guides in the Minnesota State Capitol told visitors that a layer of red roc rotunda’s second floor was Pipestone taken from Dakota quarries at what is now Pipeston Monument. 2 However, to use a stone considered sacred by the Dakota and many other In peoples simply as a decorative element in a building that symbolized those peoples’ disp from their land would be a stunning affront. Fortunately, the red stone in the Capitol rotunda is not Pipestone. Those stones exhibit re bedding and sedimentary features indicating they formed from metamorphism of cross-b sandstones. Hence, the red rocks in the Capitol rotunda are probably metamorphic quartz quarries in the Pipestone area. While that quartzite still holds significance to Indigenous p because of its relationship to Pipestone, at least it is not the stone used to create sacred that has deeply spiritual meaning to Indigenous people.

29 Question 26 – use chemical analysis to determine the rock’s bulk chemical composition – use dilute acid to see if the rock ‘fizzes’ or not (reacts with acid) Yes – try scratching the rock to see if it is harder or softer than a knife blade – prepare thin-sections of the rock for detailed microscopic petrographic study – try tasting the rock to determine whether it is salty tasting or not – use weight scales and volume scanning to determine the rock’s density Lab Conclusion [2] Only Native Americans may quarry pipestone and only with a permit, and there is a long wait list for permits s spaces are limited. During the 2013-2017 renovation of the Capitol, it was announced that the stones in the had been ‘tested’ and determined not to be Pipestone. The word ‘tested’ conjures up ima chemical analyses or detailed petrographic study by white-coated scientists in sterile lab conditions. But considering what you now know of the rocks from the Pipestone area, wha be the easiest way to confirm that these cross-bedded stones were metamorphic quartzit than metamorphic slate? Which of the following would be the simplest way to distinguish whether the red stone the Minnesota State Capitol came from the Sioux Quartzite of the surrounding Pipesto the Pipestone layer itself? This is the last lab that focuses on minerals and rocks. The remaining labs will explore oth of Earth Sciences but will continue rely on some Upper Midwest case studies.

30 - end - All lab manual materials with exception of cited illustrations © of Earth Sciences but will continue rely on some Upper Midwest case studies. Once you have completed Lab 6, be sure to SAVE your answers and the upload your completed lab to the submission page just below the Lab 6 (marked 'Use to submit completed Lab 6'). Then complete the Lab 6 Post-Lab Points activity on the lab Canvas pag activity consists of five multiple choice questions that cover the lab text concepts rather than your specific answers to the lab questions.

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59 NAME: Lily Deutsch Question 1 0 - A 0 - B Yes - C 0 - D Question 2 0 - A 0 - B 0 - C Yes - D Question 3 0 - Arkose Sandstone 0 - Breccia 0 - Chert 0 - Conglo Yes - Lithic Sandstone 0 - Quartz Sandstone 0 - Shale 0 - Siltston Which type of igneous rock was eroded and weathered to produce sand B? 0 - Andesite 0 - Basalt 0 - Diorite 0 - Gabbro Yes - Granite 0 - Rhyolite Question 4 Yes - A 0 - B 0 - C 0 - D Question 5 0 - A Yes - B 0 - C 0 - D Question 6 Based on the composition of each sand, which of the four most likely experienced the amount of chemical weathering? Based on their grain shapes, which of these sands most likely underwent the least ph weathering and transport before being deposited as sand? If sand A lithified into a sedimentary rock without any further changes in its composit grain size, what type of rock would it be? Which of these four sands is primarily to chemical precipitation rather than weatherin transportation? (Consider both grain shape as well as composition.) Based on the grain compositions present in each sand, which of the original source m these sands experienced the least amount of chemical weathering?

60 Sand B most likely formed in which type of sedimentary setting? 0 – a mountain stream 0 – a river floodplain 0 – a beach close to 0 – a beach far from rivers 0 – a lake bottom Yes – on the deep sea Question 7 0 - Arkose Sandstone 0 – Fossil. Limestone 0 - Chert Yes - Conglo 0 - Lithic Sandstone 0 - Quartz Sandstone 0 - Shale 0 - Coal Question 8 0 - A Yes - B 0 - C 0 - D 0 - E 0 Question 9 0 - A 0 - B 0 - C Yes - D 0 - E 0 Question 10 Yes – degree of weathering 0 – different source rocks Question 11 0 - long distance Yes - short distance Question 12 If sand A lithified into a sedimentary rock without undergoing any further changes in i composition or grain size, which type of rock would it be? Which of these samples is the most likely to have formed along a high-energy beach powerful surf or in a rushing mountain stream? Which of these samples is the most likely to have formed as deposits in a quiet water lagoon or on the bottom of a deep lake? Assuming samples A and C have similar-sized grain, are the differences between the likely due to their degree of weathering or to differences in their source rocks? The rock at left is composed of mud clasts ripped up during a storm. Did the storm th transport the clasts a long distance before depositing them or only a short distance?

61 0 – crystal hardness 0 – crystal shapes 0 – crystal cleavage Yes – reaction with acid 0 – rock density 0 – rock taste Question 13 Yes – size is useful in determining depositional energy for all samples 0 – size is not useful in determining depositional energy in any of the samples 0 – size is useful in determining depositional energy for B and C, but not A or D 0 – size is only useful in determining depositional energy for sample D Question 14 (Be sure to choose two properties.) Yes – its hardness 0 – its cleavage 0 – its color 0 – its flexibility Yes its conchoidal fracture 0 – its density Question 15 Question 16 Which type of depositional setting did this sequence of rock most likely form in? If you were able to handle samples A and B to test them, which characteristic would a to distinguish the dolostone from the limestone? Can you use the grain or crystal sizes of these four samples to determine the energy depositional environments? Which TWO properties of chert made it a useful rock for early stone tool makers? It is not always easy to identify rocks from a distance. However, if you were canoeing St. Croix river, how could you tell that these were sedimentary rocks, without having your canoe close to shore? If I were canoeing down the St Croix river and were looking at different rocks nearby, able to tell that the rocks I am looking and and are surrounded by are sedimentary be would be looking for layers in the rocks and what the grains look like in them. These f help me distinguish that they are sedimentary rocks because of the fact that they are the earth’s surface making them have layers, maybe fossils and a variety of grains fro

62 0 – a mountain stream Yes – a river floodplain 0 – a beach close to 0 – a beach far from rivers 0 – a lake bottom 0 – on the deep sea Question 17 Yes – dolostone only forms in tropical locations 0 – cross-bedded sandstones only form from tropical storms 0 – marine fossils suggest it must have been a tropical location 0 – pure quartz sands most often form in tropical locations Question 18 What type of metamorphic rock is this? 0 - Anthracite Yes – Gneiss 0 - Marble 0 - Ph 0 - Quartzite 0 - Slate 0 - Schist Question 19 (Be sure to choose TWO properties.) 0 – how they break 0 – how heavy they are 0 – how they ta Although you cannot tell a rock’s original latitude from its appearance, which feature( rocks’ composition supports a tropical origin for these Boom Site rocks? The rock at left has the same composition as granite. So which feature of the rock sug it is a metamorphic rock rather than a granite? With this rock having the same composition as granite, it is metamorphic and not just because of the cooling process after the magma has melted and at which rate it did. these processes of formation and their outcome, this rock will be metamorphic where cooled slowly it would become igneous and consist of mostly just minerals. The two rocks shown above are a quartzite and a marble. If you could actually handle samples, which two ways could you use to determine which rock was which?

63 Yes – if they reaction with acid 0 – if they mark paper Yes – how hard th Question 20 (Be sure to choose TWO properties.) 0 – how it breaks 0 – how heavy it is 0 – how it taste 0 – if it reacts with acid Yes – how shiny it is Yes – its color Question 21 ( Yes – formation of St. Cloud Granite 0 – volcanism of North Shore Volcanic Group Question 22 0 - Anthracite Yes – Gneiss 0 - Marble 0 - Ph 0 - Quartzite 0 - Slate 0 - Schist Question 23 0 – as far or further from Equator Yes – closer to the Equator Question 24 0 – rocks were deeply buried Yes – rocks were only buried to a shallow depth Briefly explain your answer. What feature (of one or both rocks) supports your choice? Which two properties of anthracite could you use to quickly and easily distinguish it f bituminous coal? Was metamorphism more likely due to the formation of the St. Cloud Granite or the v that produced the North Shore Volcanic Group? Considering the host rock’s properties and sedimentary structures, what type of meta rock is the host rock at Pipestone National Monument? Based on which types of sedimentary rock were originally present in this area, do you at the time the sedimentary rocks formed Minnesota was as far (or further) from the e than it is now or was it closer to the Equator? Based on their degree of alteration, do you think the Pipestone area rocks were deepl (highly metamorphosed) or only buried to a shallow depth? I think that the rocks were not deeply buried because of their crystalline features and minerals. This suggests that they needed mineral enriched soil that would not be as f deeply buried because if things kept getting burned we would hit plates.

64 Question 25 0 – increased its use because the rock would be more cohesive 0 – increased its use because the rock would be more uniform 0 – decreased its use because the rock would develop foliation Yes – decreased its use because the rock would become too hard to carve Question 26 0 – use chemical analysis to determine the rock’s bulk chemical composition 0 – use dilute acid to see if the rock ‘fizzes’ or not (reacts with acid) Yes – try scratching the rock to see if it is harder or softer than a knife blade 0 – prepare thin-sections of the rock for detailed microscopic petrographic study 0 – try tasting the rock to determine whether it is salty tasting or not 0 – use weight scales and volume scanning to determine the rock’s density NAME: Lily Deutsch If these rocks had been even more highly metamorphosed, would that have increased decreased the use of the metamorphosed pipestone for carving? Which of the following would be the simplest way to distinguish whether the red stone the Minnesota State Capitol came from the Sioux Quartzite of the surrounding Pipesto the Pipestone layer itself?

65 (1 point) Score Max. 0 1 (1 point) Score Max. 1 1 (2 points) omerate Score Max. 0 1 ne Score Max. 1 1 (1 point) Score Max. 0 1 (1 point) Score Max. 0 1 (1 point) e greatest hysical tion or ng and materials for

66 o rivers Score Max. 0 1 a floor (1 point) omerate Score Max. 0 1 (1 point) Score Max. - F 0 1 (1 point) Score Max. - F 1 1 (1 point) Score Max. 1 1 (1 point) Score Max. 1 1 (1 point) its with r coastal two most hen

67 e Score Max. 1 1 (1 point) Score Max. 0 1 (1 point) Score Max. 1 1 (2 points) Score Max. 2 (1 point) allow you of their g down the to bring I would be ecause I factors will e formed at om sand.

68 o rivers Score Max. 0 1 a floor (1 point) Score Max. 0 1 (2 points) Score Max. 1 hyllite Score Max. 1 1 (1 point) aste Score Max. 1 1 (s) of the ggests t granite Because of eas if it e the

69 hey are (1 point) es Score Max. 0 1 (1½ points) Score Max. 1.5 1.5 (1 point) hyllite Score Max. 0 1 (1 point) Score Max. 1 1 (2 points) Score Max. h 1 1 Score Max. 1 from volcanism amorphic u think that equator ly buried d solidity of found

70 (1 point) Score Max. 0 1 (½ point) Score Max. 0.5 0.5 SUM Max. 13 30 d or ne layer of one area or

71 Table 3 - Lab 5 Return to Lab 6

72 Table 2 - Lab 4 Return to Lab 6