Downtown Salem Field Trip Name: Date:

The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip Name: ______Date: ______

Team Member Name(s): ______

The purpose of this trip is to see a variety of rocks used as commercial building stone in Salem. Building stones are selected mainly for their beauty and are not normally integral to the building structures. As you’ll learn, many of these rocks were quarried from faraway places. Read the descriptions and answer the questions at each stop. Bring your textbook as it is an important resource that you will need to complete this assignment. We are using terminology in this lab that we have not reviewed in class yet, so if you find some terminology in the lab that you do not understand, you will need the textbook to help learn this new terminology.

Begin at Allann Bros. Coffee Bistro (The Beanery) at 220 Liberty St. NE, Salem, just north of the corner of Liberty and Court Streets. Walk north.

234 Liberty (in front of Café Shine) – What looks like bricks here are actually blocks of quartz sandstone painted a rust‐red color. The very fine, even layering in the sandstone tells us it was deposited in a fairly tranquil environment, possibly near a lake shore. Informally called “ribbon” sandstone.

248 Liberty (thin strip on either side of the large plate glass windows) – This igneous rock is similar to that used in the Vietnam Memorial in Washington, D.C., called “Indian Black Granite.” Don’t let the name fool you. The rock’s dark color tells us it crystallized from a mafic magma, meaning it is low in silicon/silica (SiO2) and high in the elements ______and ______.

Is the rock fine‐grained (i.e. aphanitic, with crystals too small to see), or coarse‐grained (i.e. phaneritic, with visible crystals)? ______

Based on these observations and your igneous rock charts, what is the rock name? ______

260 Liberty – This granitic rock is called “larvikite” or “blue granite.” It is not true granite, but a rare variety of light‐colored igneous rock so poor in silica (SiO2) that it contains very little if any quartz! This rock is from Finland and is known in the stone trade as “Blue Pearl.” The plagioclase crystals display an iridescent flash of colors known as the “schiller effect.” Schiller is common on plagioclase cleavage surfaces in medium‐to‐low silica igneous rocks. Schiller is caused when light scatters off different compositions of feldspar that are thinly intergrown with each other in a single crystal.

280 Liberty – (SE Corner of Liberty & Chemeketa St.) This is the oldest rock we will see today at 1.8 billion years old. That’s 1,800 million years old, or ~4.5 times older than any bedrock in Oregon! This rock is from a famous quarry in Minnesota and is called the “Cold Springs Granite.” Is it igneous, sedimentary, or metamorphic? ______

This rock formed at extremely high temperatures (high metamorphic grade) and began to partially melt.

What is this rock called? ______

Name the mafic mineral in this rock ______. How did you identify it? ______

Notice a few very large feldspar crystals; these are relict (pre‐existing) from the parent rock and have survived metamorphism. What is a likely parent rock? ______

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip Cross Liberty Street to west… then head south on Liberty.

255 Liberty – This rock is similar to 248 Liberty St. What is the rock’s name? ______

241 Liberty (PGE Bldg.) – This building had the 1950s‐era blue façade removed in 2012 to expose the original architecture and building material. What rock currently makes up the face of this building? ______

225 Liberty – Jackson’s Jewelers – This coarse‐grained igneous rock has nicely formed feldspar crystals that are dark in color and display the schiller effect. Based on crystal size, did this rock cool quickly or slowly? ______

What is the rock’s name? ______

Notice some small dikes (tabular or vein‐like igneous bodies) that cut across the rock panels in places. Some are coarser grained than the main rock and others are finer grained. Choose one dike and describe it. Approximately how wide is it? ______

Is this dike coarser‐grained or finer‐grained than the rock it has intruded into? ______

How does its composition compare to the main rock (i.e. more felsic, more mafic, about the same)? ______

Starbucks – Note the foliation (striping patterns) of the darker minerals in this light‐colored rock. If you look around the edges of some of the slabs, it will help you visualize the orientation of the foliation in three dimensions. Is the foliation sloping down toward the street or down toward the building? ______

The red mineral is fairly common in metamorphic rocks. What is it? ______

Does this rock contain at least 50% platy minerals (muscovite and biotite)? ______

Name the rock: ______

The mineral assemblage, in particular the abundance of garnet, suggest a sedimentary (clay‐rich) parent. Is this rock more or less deformed that the one we saw at 280 Liberty Street? ______

Turn west onto Court Street…

377 Court St. – India Palace Restaurant – Are the stones on this building and planter bed igneous, sedimentary or metamorphic? ______

What is the rock name? ______

Use a hand lens to look for quartz “overgrowths” on individual grains. Overgrowths here are Quartz grains were first rounded on a beach or in a stream, then were compacted and cemented into rock. After the rock formed, the old smoothed‐off faces of the quartz crystals began to re‐grow. The sparkle of the sandstone in the sunlight comes from many tiny faces of quartz crystals, reflecting sunlight like glitter.

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip The thin, flat layers/beds in the rock tell us the sediments were deposited underwater, at little at a time in a fairly calm setting, perhaps with gentle waves. What is an example of such an environment?

Head west to Commercial St. Cross the street and turn to the south…

179 Commercial St. – Look down at the sidewalk. Blocks of translucent material (which let some light pass through) are made of a mineral we saw in lab. Which one? ______

129 Commercial St. – This is an old rock, at least half a billion years old. Is it igneous, sedimentary or metamorphic? ______

What is the name of this rock? ______

It is rich in potassium feldspar. Black streaks are hornblende crystals. Does this rock contain quartz? ___

What is a possible parent rock? ______

Pioneer Trust Bank, corner of Commercial and State St. – This is extremely coarse‐grained gabbro, with plagioclase exhibiting the schiller effect. Examine the iridescent plagioclase crystals. What tells you these are plagioclase, not potassium feldspar?

Notice the concentric rings in some of the plagioclase crystals (one color in the center and a different color around the crystal edges). It is especially visible in the schiller reflections. This concentric effect is called “zoning.” Zoning is caused by the changing mineral composition that happens during crystallization. Based on Bowen’s Reaction Series, would the early‐formed crystal cores be more sodium‐ rich or more calcium‐rich than the later‐formed rims? ______(Recall from Bowen’s Reaction Series how one composition of plagioclase crystallizes first, changing composition as the temperature drops and the melt composition evolves.) Sketch one or two plagioclase crystals below, showing the zoning. Your sketch should show which areas are darker and which are lighter.

Head east on State Street, away from the river…

379‐383 State St. – Ma Valise Jewelry Store. Beautiful verde antique (green “antique marble”) facing, probably from Vermont. Actually, it is not marble at all. Builders call it “marble” because it has a hardness near calcite… but it does not effervesce in acid. This rock forms from hydration and metamorphism of peridotite as slivers of the upper mantle get squeezed up between colliding tectonic plates. What is the rock’s name? ______

What is the composition of the parent rock (e.g. felsic, intermediate, etc.)? ______

Turn left on Liberty Street and walk north.

135 Liberty St. – This stop was covered up in 2013, but you can still answer the questions. The facing stones are black brecciated metamorphic rocks, showing evidence of solution and repair by white

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip calcite. The outer panels facing the street show evidence of chemical weathering. This rock reacts with acid. What is the rock’s name? ______

155 Liberty St. – Is this rock igneous, sedimentary or metamorphic? ______

Notice elongate green‐black amphiboles (hornblende). Look for twin striations in the plagioclase. What color is the plagioclase? ______

Based on overall rock color and minerals present, is this rock ultramafic, mafic, intermediate or felsic? ______

What is the rock’s name? ______

Name a silicate mineral that you would not expect to find here: ______

Why wouldn’t it form in this rock?

Turn around and go back to State Street. Turn left (east) on State Street.

416 State St. – Key Bank at the corner of State and Liberty. The limestone bricks that face this columns are cut from coral reef limestone that has been somewhat recrystallized. Note the high porosity and permeability typical of the sponge‐like reef rock. Can you see fossil coral? ______

In the Middle East ancient reefs make superb reservoir rocks for oil and gas.

The floor in front of the entry is fine‐grained travertine that dissolved from the coral reef limestone and recrystallized. Recall that travertine is a freshwater limestone. What mineral are all these rocks made of? ______

What affect does rain have on these rocks – and why?

Continue east on State Street and cross the street at High Street.

Corner of State and High Streets (512‐516 State St.) – The Marion County Courthouse is faced with a white metamorphic rock from Vermont. What mineral is it mostly made of? (hint: if you put a drop of acid solution on it, it would fizz vigorously) ______

What is the rock’s name? ______

Despite the streaks, this rock is not foliated. Look closely with a hand lens to determine what light‐ colored mineral forms thin streaks in the rock?

What is the metallic mineral here? ______

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip Walk east on State Street.

Corner of Church and State Streets – Old Salem Post Office. Does this white facing stone look similar to the last building? ______

This rock is also from Vermont. Here, the darker streaks in the rock include a yellow metallic mineral. The crystals do not look cubic as they might for pyrite. Can you identify this mineral? What is it? ______

The foundation stone and steps of this building are very weathered granite.

Continue east on State Street and cross State Street at Cottage to the Art Museum.

Corner of Cottage and State Streets – Hallie Ford Art Museum. Above the doors is another white metamorphic rock, again from Vermont. Now look down at your feet. What metamorphic rocks pave the entry to the museum? ______

How did you identify it? ______Multi‐colored rings called “Liesegang bands” are a pattern in the rock created by ground water flowing through the rock and consequent weathering.

Continue east on the sidewalk and you will see that the building has a light‐colored rock above and a darker, gray‐brown rock below. The darker rock consists of milky‐brown plagioclase crystals, black biotite, and possibly hornblende. This may be a simple diorite or possibly a cousin of the rare silica‐ deficient larvikite (“blue granite”) we saw at our third stop. Do these plagioclase crystals display schiller iridescence? ______

Note the arrangement of the crystals. This arrangement may be due to magma flow or crystal settling. Choose an area about 10‐14 cm square and sketch the arrangement of the large plagioclase crystals in relation to one another:

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip

Turn south through the alley alongside Hallie Ford Museum. Then turn immediately left and cut through the parking lot, cross Winter Street. Continue up the wide sidewalk onto the Willamette University campus past the small Japanese garden.

Observe the erratic from the Missoula Floods with a plaque – Contrary to the date cited on the plaque, this boulder was deposited in Oregon 13,000‐11,500 years ago, when we now know that catastrophic floods repeatedly filled the Willamette Valley with sediment‐laden water and mini‐icebergs from glacial Lake Missoula in western Montana. Is this boulder well‐rounded? ______

This rock has traveled far. Why isn’t it worn smooth and round from abrasion along its journey?

Redwoods ‐ These trees (Sequoiadendron giganteum) are the Giant Redwoods. They are related to “dawn redwoods” (Metasequoia glyptostroboides), a variety that once dominated vast areas of western North America after the demise of the dinosaurs. Dawn redwoods were fossilized from 5 to 25 million years ago in what is now the John Day Fossil Beds National Monument and elsewhere in North America. Dawn redwoods (Metasequoia) recently became Oregon’s official state fossil.

In 1944 a forester shocked the world by finding a grove of living dawn redwoods in a remote area of China. Since then, scientists have collected seeds and brought this fossil tree to life again on our continent!

Continue east on the path, past Town and Gown, to Eaton Hall.

Eaton Hall – The foundation of this building is a tuffaceous sandstone – that is, a sandstone made mostly of sand‐size grains of pyroclastic volcanic material. In what year was this building constructed? _____

Describe and sketch the effects of weathering on this rock:

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip

Cross the street toward the Capitol Building.

Back side of the Capitol Building – Surprise! This building is faced with white Vermont marble. How does it look different from the marble at the Marion County Courthouse and the Old Post Office (page 4)? ______

What mineral(s) besides calcite can you identify here?______

How did you identify it? ______

Walk around the north side of the Capitol Building, on the walkway through the small park.

Circuit Rider statue – Is this rock igneous, sedimentary or metamorphic? ______

Does it contain quartz crystals? (You may see this better if the rock is wet.) ______

Look closely with a hand lens to identify the mafic (dark‐colored) mineral, what is it? ______

Is the rock plutonic or volcanic? ______

What is the rock’s name? ______

Explain why this is the best name:

Stand back and notice the large, faint, dark smears in the rock. These are called “schlieren” and were formed from chunks of more mafic rock that were incorporated into the magma and were in the process of melting, just as the magma began to cool and harden. The largest remaining chunk or “xenolith” (“foreign rock”) is about 2 cm long. Its quartz appears milky – possible evidence that the solid piece was starting to melt.

Jason Lee and McLaughlin statues – The bases of these statues are very similar in composition to the first statue. What rock texture do you see here that was not at the Circuit Rider statue? ______

What mineral crystallized to make the large, well‐formed crystals? ______(Your knowledge of Bowen’s reaction series and the order that silicate minerals crystallize may help here.)

Oregon Veterans Medal of Honor Memorial – What is the rock name for the plaque podiums? ______Again, the composition is similar to the previous monuments. All have little to no potassium feldspar, which is typical of Oregon rocks.

On the north side of the column dedicated to Gary Martini is a large white plagioclase crystal showing excellent twin striations. You won’t need a hand lens to see them!

Were these monument stones erected before or after those at the two previous stops? ______

How can you tell (other than reading the date!)?

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip

Go to the front of the Capitol Building.

Capitol Building Entrance – The steps and building foundation are a gray granitic rock with chunks of other rocks (xenoliths) incorporated into it. When you see xenoliths, it usually means the stone was quarried from the top or edges of a pluton, near the border with the surrounding rocks. Are these xenoliths more mafic or more felsic than the rest of the rock? ______

Inside the Capitol (if open) – The rotunda floor is gray fossil‐bearing limestone and/or marble of Paleozoic age. The black stone is Cretaceous age fossil‐bearing limestone. Walls are Cretaceous reefoid limestone with solution cavities that have been filled with grout of some kind. Flesh pink and tan colors in the walls come from iron oxides (hematite and limonite). There is a nice mineral display in the case in the hall on the right that has changing displays of minerals, etc.

Exit and head to the west side of the Capitol Building.

“Marking an Old Trail” monument – This boulder is quite weathered and altered at its surface, but you may find a relatively freshly‐broken surface that reveals the rock inside. Note the year it was placed here: ______

What mineral would make the weathering rind reddish? ______

This mineral indicates a high content of what chemical element in the rock? ______

Find a surface that exposes fresh rock without lichens or rust. What color is the rock? ______

Is it fine‐grained (aphanitic) or coarse‐grained (phaneritic)? ______

Therefore, is it intrusive? _____

What is the rock name? ______

Is the rock likely native to Oregon? ______

Why do you think so?

Oregon Tribes plaques –What is the rock name? ______

The reddish color is common for what type of feldspar? ______

Was this rock likely quarried in Oregon? _____

Why do you think so?

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip

Continue west across the park to the painted cast iron fountain at the far west end, next to Cottage Street.

Small round fountain – The cast iron in the fountain is almost certainly from the Lake Oswego area where it was mined and smelted from the iron hydroxide mineral, limonite.

The pavers around the fountain are made of limestone and travertine. The travertine is similar to what we saw at Key Bank. You can see layering in it. The contorted zig‐zag lines, on the other hand, occur in the limestone and are evidence that the rock partially dissolved under extreme pressure. Is the rock travertine more likely to form near the surface or to be deeply buried? ______

Identify which pavers are travertine and which are limestone? Describe how the two rocks look different from each other with regard to their porosity, density and colors.

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The Geology of Pacific Northwest Rocks & Minerals GEO143: Downtown Salem Field Trip This concludes your Geologic Tour of Urban Salem. Turn this in at our next class meeting.

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Walking directions to Court St NE & Church St NE, Salem, OR 97301 1.4 mi – about 27 mins

220 Liberty St NE Salem, OR 97301 1. Head north on Liberty St NE toward Chemeketa St NE 207 ft 207 ft – about 46 secs

280 Liberty St NE Salem, OR 97301 2. Head south on Liberty St NE toward Court St NE 207 ft 207 ft – about 45 secs

225 Liberty St NE Salem, OR 97301 3. Head south on Liberty St NE toward Court St NE 131 ft 4. Turn right at Court St NE 125 ft Destination will be on the right 256 ft – about 1 min

377 Court St NE Salem, OR 97301 5. Head west on Court St NE toward Commercial St NE 318 ft 6. Turn left at Commercial St NE 282 ft Destination will be on the right 0.1 mi – about 2 mins

129 Commercial St NE Salem, OR 97301 7. Head south on Commercial St NE toward State St 157 ft 8. Turn left at State St 351 ft Destination will be on the left 0.1 mi – about 1 min

379 State St Salem, OR 97301 9. Head east on State St toward Liberty St SE 105 ft 10. Turn left at Liberty St NE 66 ft Destination will be on the left 171 ft

135 Liberty St NE Salem, OR 97301 11. Head north on Liberty St NE toward Court St NE 194 ft 194 ft

155 Liberty St NE Salem, OR 97301 12. Head south on Liberty St NE toward State St 256 ft 13. Turn left at State St 125 ft Destination will be on the right 381 ft – about 1 min

416 State St Salem, OR 97301 14. Head east on State St toward High St NE 430 ft Destination will be on the right 430 ft – about 1 min

512 State St Salem, OR 97301 15. Head east on State St toward Church St SE 338 ft 338 ft – about 1 min

State St & Church St NE Salem, OR 97301 16. Head east on State St toward Cottage St SE 446 ft 446 ft – about 1 min

State St & Cottage St NE Salem, OR 97301 17. Head east on State St toward Winter St SE 446 ft 446 ft – about 1 min

State St & Winter St SE Salem, OR 97301 18. Head west on State St toward Cottage St NE 446 ft 19. Turn right at Cottage St NE 436 ft 20. Turn right at Court St NE 0.2 mi Destination will be on the right 0.3 mi – about 6 mins

Oregon State Capitol 900 Court Street Northeast Salem, OR 97301 21. Head west on Court St NE toward W Summer St NE 0.3 mi 0.3 mi – about 4 mins

Court St NE & Church St NE Salem, OR 97301

These directions are for planning purposes only. You may find that construction projects, traffic, weather, or other events may cause conditions to differ from the map results, and you should plan your route accordingly. You must obey all signs or notices regarding your route. Map data ©2010 Google

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Oregon State Capitol

State Street

Star Trees 24 23 38 3 22

27 17 11 13 47 31 37 53 18 9 56 35 Ferry Street 54 44 45 Ferry Street Church Street 4 Cottage Street 16 42 10 Quad 8 19 29 15 1036 50 7 12 33 P r 20 21 32 in 49 g l e 46 P a

r Street Street k Permit w Mill Race Parking Lot th th

a 25 12 14 y Jackson Plaza 26 5 56 41 40 48 Permit Hatfield Parking Lot 30 Fountain

Mill Street Mill Street Permit Sparks Field 52 1 Parking Lot 51

Winter Street 43 39 14 55 Permit 2 Parking Lot 28 Visitor Parking Lot Tennis Courts

Bellevue Street Softball Field Parking Oak Street Lot

Salem Hospital Campus Leslie Street Capitol Street University Street

Mission Street

1 Admission Office (CLA) 22 Ford Hall 43 Shepard House 2 Alpha Chi Omega Sorority 23 Hallie Ford Museum of Art 44 Sigma Chi Fraternity 3 Art Building 24 Gatke Hall 45 Sigma Alpha Epsilon Fraternity 4 Atkinson Annex 25 Goudy Commons 46 Smith Auditorium 5 Atkinson Graduate School of Management 26 Mark O. Hatfield Library 47 Smullin Hall (Seeley G. Mudd Building) 27 Haseldorf Apartments 48 Lestle J. Sparks Center 6 Baxter Hall 28 Kaneko Commons 49 Terra House 7 Belknap Hall 29 Lausanne Hall 50 Theatre Playhouse 8 Beta Theta Pi Fraternity 30 Lee House 51 Tokyo International 9 Bishop Wellness Center 31 Mahoney Building University of America 10 Campus Safety 32 Mary Stuart Rogers Music Center 52 University Apartments 11 Centers for Academic Excellence (Hudson Hall) 53 Waller Hall 12 College of Law 33 Matthews Hall 54 Walton Hall (Truman Wesley Collins Legal Center) 34 McCulloch Stadium and Athletics Complex 55 Willamette International Studies House 13 Collins Science Center 35 Montag Center (WISH) 14 Delta Gamma Sorority 36 Office of International Education 56 York House 15 Doney Hall and the Writing Center 16 Doney North Offices 37 Olin Science Center Handicapped Access 17 East House 38 Oregon Civic Justice Center Emergency Telephone 18 Eaton Hall 39 Pi Beta Phi Sorority Automated External Defibrillator 19 Executive Building 40 Physical Plant Short-term Parking Meters 20 Fine Arts West 41 Putnam University Center 21 Fine Arts East 42 School of Education and 9/18/09 Willamette Academy