1. Chapter 2: Utah’s Geology
The Ice Age

2. Bell Activity
This is a no gum class. Please dispose of it properly!
Read page 36-37, answer the questions on the back of the tan paper, also answer questions on your study guide.
If you finish these questions early, work on the rest of your study guide. It is homework unless you find time during school to get it done!!
Where should your backpack be?
How the Earth was Made

3. Today we will be learning about…
Social Studies Objective – We will be able to explain what the environment of Utah was like during the Ice Age and how that time period affects us today.
Behavior Objective – Courtesy & Respect: Your behavior does not cause a problem for others or for yourself.
Language Objective –
We will listen to the presentation and use the information we gather to write an essay outline.
Explain how natural forces shape the living environment and landscape.
Investigate how natural forces shape the local environments.
Predict how natural forces affect environments; e.g., earthquakes, volcanic action, mudslides, flooding, erosion.

4. Posters
As long as your poster has all the information it should, you can design it how you want.
For those of us who like a little guidance, here is what your first poster might look like…

5. We will watch a short video about the era, then read a short description of it, and finally, talk about what happened in Utah at this time.
Cenozoic Era

6. Cenozoic Part 2

7. Percentage of Time: Deep time demonstration
Let’s see how much of Earth’s geologic history was taken up by this era.
If we converted the whole history of the earth into a timeline 5 feet long, how much of line would the Cenozoic Era take up. (Math!!! 60 inches x 17.5% = _______ inches)
Hadean 17.5%
Archaen 28.5%
Proterozoic 42%
Paleozoic 7%
Mesozoic 4%
Cenozoic 1%
10.5 inches ~10.5”
17.1 inches ~17”
25.2 inches ~25”
4.2 inches ~4”
2.4 inches ~2.5”
0.6 inches ~0.5”

8. Let’s work Read with your group about the era in your folders.
Choose the five most important events of the era.
Choose the event you think was the most important and explain why it was.
Then fill out the section about cool organisms of the era.
Most cool events important or facts written in complete
sentences
picture
3+ cool living What is
organisms happening in and a picture Utah?
Of them

9. Utah is an environment that has been shaped by many natural forces.

10. The Ice Age
The last major event that shaped the world, and Utah, occurred 10,000-20,000 years ago.
At this time the world was engulfed in an ice age.
How the Earth was Made - 1:17:30 - 1:24:30

11. Ice Ages Throughout Geologic Time
Quaternary
Ice Ages Throughout Geologic Time
Figure modified after C.R. Scotese
PALEOMAP Project (
Ice Ages Throughout Geologic Time
The Quaternary Period is the latest period of geologic time. It is made up of two epochs, the Pleistocene and the Holocene, or present. The Pleistocene Epoch is Earth’s most recent Ice Age. An ice age is a long period of time when temperatures are relatively cold and large areas of the Earth are covered by ice. The time that we typically think of as the “Ice Age” peaked about 18,000 years ago during what is called the Last Glacial Maximum. We are presently living in an interglacial, or warm period, between glacial episodes in the current ice age that began about 3 million years ago (Pleistocene Epoch).
Ice ages have occurred numerous times throughout geologic time. Major ice ages occurred during the Precambrian (~ million years ago), the Ordovician to Silurian (~ million years ago), the Carboniferous to Permian (~ million years ago), and the Pleistocene to Holocene (~3 million years ago to present).
12°
22°
17°
Average Global Temperature (0C)

12. Glacier Maximum
Over thousands of years the ice grew, covering much of present day North America.
Then about 18,000 years ago, the massive glaciers began to recede.

13. The Ice Age in Utah
Although the ice sheets did not cover Utah, there is evidence of the ice age all across the state.
Glaciers were prevalent in the mountains.
When they receded they left basins filled with water.
These basins are an important source of water and recreation in the state.
Bear Lake photos. (broken link)

14. Tony Grove
At Tony Grove in Logan Canyon, there is evidence everywhere of a glacier being present and shaping the land.

15. Denali National Park, Alaska
Glacial Erratics
Voyageurs National Park, Minnesota
Glacial Erratics
Erratics are rock fragments that have been carried by glacial ice and deposited some distance from their original source. Erratics can be as small as a pebble to as large as a house! Note the person in the lower photograph for scale.
Denali National Park, Alaska
Person

16. Glacial Polish and Grooves
Grooves and polish on bedrock
Glacier National Park, Montana
Glacial Polish and Grooves
Glacial ice contains a lot of rock fragments and debris that help to erode bedrock at the base and sides of a glacier. Small fragments such as sand tend to polish and smooth the surface of the bedrock. Larger pebbles can carve out parallel striations or grooves on the bedrock as they move along with the ice.
Striations

17. Erratics & Scouring
Boulders are scattered around the land leading to the lake.
The rocks around the lake have deep scrapes from heavy ice and boulders rubbing the surface.

18. Holgate Glacier, Alaska
Holgate Glacier, Kenai Peninsula, Alaska
This glacier on the Kenai Peninsula is one of several glaciers from the Harding Icefield. Can you picture what the valley looks like beneath the glacier?

19. Lake in a U-valley The valley the lake is in is called a cirque.
The rock amphitheatre around the lake was carved by the thick snow and ice.
Other lakes in the area were formed in the same way.

20. Wellsville Mountains
You can also see evidence of glaciers in the mountains that surround Cache Valley.
The benches are also evidence of an ice age.
Glacial Cirque

21. Lake Bonneville and Ice Coverage in Utah During the Late Pleistocene ~18,000 years ago
Uinta Mountains
Wasatch
Range
Lake Bonneville and Ice Coverage in Utah During the Late Pleistocene ~18,000 years ago
This map shows Lake Bonneville and the maximum extent of ice coverage in Utah about 18,000 years ago. Notice the broad expanse of ice that covered the Uinta Mountains! The Wasatch Range also underwent some glaciation during the most recent ice age. The power of these large glaciers hundreds of feet thick left their mark on the mountainous landscape of the Wasatch, creating most of the beautiful mountain scenery we have today. The cooler, wetter climate in the late Pleistocene caused Lake Bonneville to rise to its maximum level and large amounts of snow and ice to accumulate in mountainous regions.

22. The Rise and Fall of Lake Bonneville
Provo Level
17,000 years ago
Great Salt
Lake today
Bonneville Level
18,000 years ago
Gilbert Level
12,000 years ago
The Rise and Fall of Lake Bonneville
The hydrograph for Lake Bonneville represents lake levels over the past 24,000 years. Maps of Lake Bonneville (background) indicate when the four major shorelines were formed; Stansbury, Bonneville, Provo and Gilbert. The location of present-day Great Salt Lake is depicted in dark blue.
Hydrograph of Lake Bonneville
Stansbury Level
24,000 years ago

23. Great Salt Lake Today ID NV UT Ogden Salt Lake Provo Nephi Delta
Red Rock Pass
Great Salt Lake Today
Great Salt Lake Today
This map depicts present-day Great Salt Lake. Great Salt Lake is the largest remaining remnant of Lake Bonneville. Other relics of Lake Bonneville are Utah Lake, Sevier Lake, and the Great Salt Lake Desert containing the famous Bonneville Salt Flats. The chemical composition of Great Salt Lake is similar to that of typical ocean water. Sodium and chloride are the major ions in the water, followed by sulfate, magnesium, calcium, and potassium.  Although much of the salt contained in the Great Salt Lake was originally in the water of Lake Bonneville, a small amount of dissolved salts is deposited in the lake every year by rivers and numerous small streams that feed into it. As the lake rises, its salinity drops because the same amount of salt is dissolved in more water. In historical time, the lake's salinity has ranged from a little less than 5% (just above that of sea water) to nearly 27% (beyond which water cannot hold more salt).

24. Bonneville Salt Flats Bonneville Shoreline Provo Shoreline Salt
The Bonneville Salt Flats can be seen from I-80 near Wendover, Utah. When Lake Bonneville evaporated, salt from the water was left behind on the dry lake bed. The Bonneville Salt Flats are one of the flattest areas on earth and are the site of many land-speed records set by race cars.
In the background, the Bonneville and Provo shorelines can be seen on the Silver Island Range.
Salt

25. Bonneville Shoreline ~18,000 years ago
Red Rock Pass UT ID NV
Bonneville Shoreline
~18,000 years ago
Ogden
Delta
Nephi
Provo
Salt Lake
Point of the Mountain
Bonneville Shoreline ~18,000 years ago
This map depicts Lake Bonneville about 18,000 years ago. This is the highest stage of Lake Bonneville and at this time the lake level was controlled by a threshold near Red Rock Pass, Idaho. About 17,500 years ago, the threshold broke and water spilled out catastrophically into the Snake River drainage. This event is called the Bonneville flood. It is estimated that in less than one year, the amount of water that flowed out of Lake Bonneville was equivalent to all of the freshwater flowing in the world today!
One of the best places to view the Bonneville shoreline is at Point of the Mountain in Draper, Utah. The flat bench extending from Point of the Mountain to the east was formed by waves and currents in Lake Bonneville.

26. Shorelines of Lake Bonneville at Antelope Island
Provo
Unnamed shoreline
Stansbury
Gilbert
Unnamed shoreline
Shorelines of Lake Bonneville on Antelope Island
Well-defined shorelines are visible at Buffalo Point on the northwest side of Antelope Island. Notice that there are more than four shorelines present. Dozens of unnamed shorelines associated with the oscillations of Lake Bonneville can be seen around the Bonneville basin.

27. Bonneville Shoreline at Point of the Mountain
Bonneville Shoreline at Point of the Mountain (view to the southwest)
This once pristine shoreline near Draper, Utah, is now the site of subdivisions and an expanding gravel pit. The site is also a popular hang gliding and paragliding launch spot. Note the paragliders flying above the ridge on the inset to the right. With increasing building and excavation in this area, pilots are running out of places to land!
Paragliders

28. Lake Bonneville Barrier Bar and Spit Modern Barrier Bar and Spit
Kiawah Island, South Carolina
Lake Bonneville
Barrier Bar and Spit
Lake Bonneville Barrier Bar and Spit
(view to the north, from highway SR 36)
The lower photo is of the Stockton Bar, located in Tooele County, Utah. The Stockton Bar is a composite of barrier bars and spits that formed in Lake Bonneville when it was near its highest level. The Stockton Bar formed much in the same way as the modern barrier bar and spit at Kiawah Island, South Carolina.
A spit forms when sediment is transported along a shoreline and is deposited in a fingerlike extension into a body of water. A barrier bar is simply a spit that has extended all the way across a body of water and has become attached to the shoreline on both ends.
Modern Barrier Bar and Spit
Stockton Bar, Utah

29. Lake Bonneville Deep-Water Sediments
Sediment layers from Lake Bonneville
Lake Bonneville Deep-Water Sediments
Most sediments in deep water are very fine-grained silt and clay and settle very slowly to the lake bottom. Many of these deposits are finely layered (laminated), indicating a change in lake chemistry or sediment input.

30. Bonneville Cutthroat Trout
Today are isolated in streams that once drained into Lake Bonneville.
Bonneville Cutthroat Trout
The Bonneville cutthroat trout, (Oncorhynchus clarkii utah) is a subspecies of the cutthroat trout native to the Bonneville Basin of Utah, Wyoming, Idaho, and Nevada 30,000 years ago. Today, the Bonneville cutthroat trout live in more restricted populations and are found in isolated streams that once drained into Lake Bonneville.
In the past decade a tremendous effort has been underway to bring back the native Bonneville cutthroat populations. In 1978 only six remaining populations of Bonneville cutthroat trout were known to exist in Utah, and they occupied less than five stream miles. By 2001, Division of Wildlife Resources biologists estimated at least 166 populations existed along 630 miles of streams.
Known Distribution

31. The Lake Bonneville flood
At Red Rock pass in Idaho, the waters of Lake Bonneville broke through a barrier of land and the resulting flood carved much of the Snake River valley.
Over the course of several weeks, the lake drained to the Provo level.
The Lake Bonneville flood

32. Shorelines of Lake Bonneville at Antelope Island
Provo
Unnamed shoreline
Stansbury
Gilbert
Unnamed shoreline
Shorelines of Lake Bonneville on Antelope Island
Well-defined shorelines are visible at Buffalo Point on the northwest side of Antelope Island. Notice that there are more than four shorelines present. Dozens of unnamed shorelines associated with the oscillations of Lake Bonneville can be seen around the Bonneville basin.

33. Life in Utah at the end of the Ice Age
This is a scene from the Ice Age mural by Joseph S. Venus at the College of Eastern Utah Prehistoric Museum in Price, Utah. It is a reconstruction of Ice Age life found in Utah.

34. Utah’s Giant Ice Age Birds
Teratornis-
“giant condor”
Utah’s Giant Ice Age Birds
The teratorns are closely related to vultures and condors, which were also found in large numbers in the Great Basin during the Ice Age. These impressive giant birds had a wingspan of roughly feet or more and weighed 35 pounds. They had a hooked, somewhat eagle-like beak. The decline of the condors, teratorns, and vultures in western North America sometime toward the end of the last Ice Age coincides with the extinction of large mammals such as mastodons, giant sloths, camels, and saber-toothed cats that these giant birds fed on.
The California condors are among the largest flying birds in the world. Adults weigh approximately 22 pounds and have a wing span up to 9½  feet. During the late Pleistocene the condor could be found in great numbers all over the southwestern United States. Currently the California condor is endangered and a recovery program is underway to re-establish the species through captive breeding. Today condors are being reintroduced into the mountains of southern California, the central California coast, and near the Grand Canyon in Arizona.
Teratornis skeleton
Endangered California Condor
Teratornis skull

35. Ice Age Elephants Mammoth Mastodon The Huntington Mammoth
Ice Age Elephants - Mammoths and Mastodons
Mammoths (Mammuthus) and mastodons (Mammut), members of the order Proboscidea, are extinct relatives of living elephants that were common throughout the Ice Age of North America. The mastodons evolved in Africa about 35 million years ago and spread throughout Africa, Europe, and Asia. About 3.7 million years ago mastodons migrated to North America via the Bering Land Bridge. The mammoths appeared in sub-Sahara Africa about 3-4 million years ago, migrated across Europe, Asia, and Berengia, and eventually crossed over the Bering Land Bridge into North America about 1.7 million years ago. Both the mastodon and mammoth became extinct at the end of the Ice Age, about 10,000 years ago.
Mammoth Mastodon
The Huntington Mammoth
(Mammathus columbi) skeleton at the CEU Prehistoric Museum
Detail from Joseph S. Venus mural, College of Eastern Utah (CEU) Prehistoric Museum, Price, Utah

36. Mammoth & Elephants vs. Mastodons
Elephants and mammoths have high skulls, while mastodons have low skulls.
Columbian Mammoth (M. columbi)
Mammoths & Elephants vs Mastodons
Columbian mammoths (Mammathus columbi), a species adapted to open habitats, have been found from the northern reaches of North America into Mexico. The Columbian mammoth was a descendent of Mammuthus meridionalis, the ancestral mammoth that entered North America via the Bering Land Bridge about 1.7 million years ago. Mammoths are more closely related to modern elephants than mastodons. North American mammoths had flat, high-crowned teeth, well suited for the grinding of grasses. Their distribution also reflects this; their remains are most abundant in the rocks and sediments of open grasslands. They could reach a height of 11 feet at the shoulder (comparable to the size of an African elephant).
The American mastodons (Mammut americanum) roamed North America from at least 3.7 million to 10,000 years ago. Mastadons’ teeth were pointed, enamel-covered cones, well suited for their diet of herbs, shrubs, and tree bark. Unlike mammoths these animals were browsers living in open woodlands. They were massive, stockier in build than mammoths and modern elephants. They were also shorter, standing about 9 to 10 feet at the shoulder.
American Mastodon (Mammut americanum)
Elephants and mammoths have low, highly enfolded teeth for grazing, while mastodons have high crested teeth for browsing leaves.
Elephants and mammoths are tall, while mastodons are shorter with more massive bodies.

37. Saber-toothed Cat Skeletal reconstruction and detail from
Smilodon fatalis
Saber-toothed Cat
The saber-toothed cat (Smilodon) from the Late Pleistocene was the size of a lion and had enlarged canines that looked like small elephant tusks. Unlike lions, which have long tails that help provide balance when the animals run, Smilodons had bobtails which suggests that they probably did not chase down prey, but charged from ambush instead, waiting for prey to come close before attacking. The saber-toothed cat went extinct about 10,000 years ago. A few bones of the species Smilodon californicus have been found near Park City.
Skeletal reconstruction and detail from
Joseph S. Venus mural, CEU Prehistoric
Museum, Price, Utah

38. Giant Ground Sloth
Giant Ground Sloth
The extinct giant ground sloths of North America, relatives of the modern South American tree sloths, migrated from South America during the late Pleistocene. Two species of ground sloth lived in Utah during the Ice Age. Jefferson’s ground sloth (Megalonyx jeffersoni), named after the third President of the United States, Thomas Jefferson, was the size of a bison. Harlan’s ground sloth (Glossotherium harlani) was larger than the Jefferson’s ground sloth and had small pebble-like bones under its skin, which may have served as armor against predators.
Skeletal reconstruction and detail from Joseph S. Venus mural, CEU Prehistoric Museum, Price, Utah

39. Other Extinct Ice Age Mammals
Camel, horse (not pictured), long-horned bison, and musk ox fossils have all been found in Utah. Horses evolved in North America and crossed into Asia via the Bering Land Bridge. They became extinct at the end of the Ice Age, only to be reintroduced by European settlers. Camels, like horses, are also New World natives that evolved here and entered Asia via the Bering Land Bridge. Unlike horses, however, some of the camel family – llamas, survived the Ice Age. Bison evolved in Eurasia and migrated to North America near the end of the Ice Age. Two extinct species of long-horned bison found in Utah are close relatives of our modern bison. The helmeted musk ox (Bootherium bombifrons) was one of five different kinds of muskoxen that lived in North America during the Pleistocene. However, it appears to have been the only one to have evolved and remained restricted to North America. It is the most common mammal fossil found along the shores of ancient Lake Bonneville. Two new sites have produced partial skulls of these muskoxen. One is from a gravel pit near the Kennecott Copper Mine west of Salt Lake City, and the other is from the construction site of the Huntsman building at the University of Utah.
Extinct Long-Horned Bison
Extinct Musk Ox
Camels, together with native horses, went extinct in North America at the end of the Ice Age

40. Ice Age Land Bridges and Mammal Migrations
Mammoths, mastodons, and bison migrated from Eurasia to North America. Camels and horses migrated from North America to Eurasia. Camels, deer, rabbits, rodents, dogs, and cats migrated from North America to South America. Ground sloths, porcupines, and armadillos migrated from South America to North America.

41. Ice Age Animal – Size Comparisons
American Lion
Ice Age Animal – Size Comparisons
Sabertooth Cat
Mammoth

42. These and other animals went extinct at the end of the ice age.
Giant Armadillo
Many people have tried to explain why, but (just like with the dinosaurs) there are many theories that are plausible.
One of them involves new comers on to the scene in Utah…humans.

43. Let’s work
Check your work for completeness and accuracy.

44. Essay practice: Let’s use what we have just learned to create an essay outline.

45. Now try it for yourself.

46. Bell Activity
This is a no gum class. Please dispose of it properly!
Read page 35 and answer questions on your study guide.
If you finish these questions early, work on the rest of your study guide. It is homework unless you find time during school to get it done!!
Where should your backpack be?
How the Earth was Made