Does this look like fun?
For many geologists, a day hiking in beautiful country to learn more about the interesting geology is about as good as it gets!
Many Earth scientists collect data in the field. The data may be from observations or measurements. The scientists may create a geological map of the area, write detailed descriptions, or collect samples to analyze in the lab. Or a combination of all of these! Many Earth science laboratories contain high-tech equipment to reveal the chemistry or age of a rock sample. Field work is done to look for resources, for environmental cleanup, or for any number of other reasons. One common reason is just to understand the region better.
To really understand geology and some of the other branches of Earth science, it's best to go out in the field! Some of the concepts presented here focus on regions where geologically interesting features can be seen. In these cases, a location is presented and the phenomena of interest described. It's just like we're going on a field trip! These field trips are great because they don’t involve long drives in a car, expensive airplane trips, or a passport! We can do things that are difficult or impossible to do on an ordinary field trip. We can go to any single location on Earth, we can hop along a latitude line, visit the bottom of the ocean, or look to different areas for a specific phenomenon.
Of course, we won't be enjoying the fresh air, exercise, camaraderie, or thrill of discovery in the same way we would on a real field trip, but, hey, you can't have everything! What follows is a brief synopsis of some of the places we'll be visiting. Where possible, we've tried to visit locations in the western United States, an area that may be familiar to you.
Major geographic features of California.
In the satellite image in the Figure above , it is possible to identify the major geographic features of California.
- The Coast Range runs the length of the state along the Pacific coast. A tremendous amount of rain falls in the northern part of the range, so the region is heavily forested. Further south, rainfall and vegetation are more sparse.
- The Central Valley, made up of the Sacramento and San Joaquin river valleys, runs through about half of the central part of the state is located inland from the Coast Range. The collection of river sediments and the abundance of water has made the Central Valley one of the most important agricultural regions in the world.
- The Sierra Nevada Mountain range lies east of the Central Valley. In the winter the mountains are covered by snow, but in this image there is little to no snow and the bare rocks of the high peaks are showing, particularly in the southern portion of the range. Yosemite National Park lies within the Sierra Nevada.
- East of the Sierra Nevada and into the state of Nevada, the climate is very arid. Death Valley, the driest spot in the United States is found there.
- Mt Shasta, at the north end of the Sierra Nevada, is the southernmost remaining volcanic cone in the Cascades Range.
East of the image of California is Nevada. Very different from California, Nevada is extremely arid. The Basin and Range province, which consists of a set of mountains and valleys, is best displayed in the state. You can see the ranges as dark brown rocky regions and the valleys as lighter brown. The ranges have been described as worms crawling northward across the state, which is what they look like in this image.
North of California along the Pacific Coast is Oregon, Washington and then British Columbia in Canada. This region is similar to California in having a coastal range, a central valley (at least in part of Oregon) and very arid lands east of the high Cascades mountains.
The Cascades are volcanoes that begin with Lassen in California, run through Oregon and Washington, and continue into British Columbia. Some of them are easily spotted on this image as white spots in the midst of the green forests of the Cascades range.
The closeup image of Mount Hood taken by an astronaut on the International Space Station shows one of the most distinctive of the Cascades composite volcanoes. Solidified lava makes up the summit of the mountain and glaciers are found on both the north and south sides of the peak. Mount Hood is the northernmost Cascade volcano in Oregon and is just south of Mt. St. Helens.
Idaho, Montana, Wyoming
This image shows the states of Idaho, Montana, Wyoming, with a little of Utah and a few others. The northern part of Idaho and northwestern Montana is mountainous and forested. Arid lands lie to the east.
Glacier National Park
This satellite image of GNP in summer shows snow-capped peaks and glacial valleys, many of which are now lakes.
Glacier National Park in the northwestern part of Montana reaches to the Canadian border. North of the border the park becomes the Canadian Waterton Lakes National Park. Although Glacier National Park was established in 1910 to preserve the wild lands and wildlife, the glaciers have been reduced by a reduction in precipitation and higher summer temperatures. On glaciers, snowfields, or just rock, Glacier National Park is a fantastic place to see glacial features, beautiful scenery, and wildlife.
Naturalists enjoy the hike to Iceberg Lake in Glacier National Park.
Yellowstone National Park
Grand Prismatic Spring is one of the spectacular features of Yellowstone National Park.
Yellowstone National Park is in the northwestern corner of Wyoming. Although Yellowstone is best known for its incredible geysers, the park also has gorgeous mountain scenery and fantastic wildlife, including herds of amazing bison. The best known feature is Old Faithful, a geyser that's not the highest, largest, or most beautiful, but is the most reliable.
Bison are just some of the amazing creatures that roam around Yellowstone.
The Southwest is home to mountains, canyons, valleys, and flat lands. Many features discussed in the Earth Science concepts can be seen in the Southwest.
The Southwestern United States is a great place to study geology. The region is so arid that in most locations rocks and structures are easily seen. In several concepts we will visit parts of the Southwest to view geology in the field.
From the rim, the Grand Canyon gives a sense of the vastness of geologic time and the immensity of the planet.
Geologists say that the Grand Canyon has "layer cake geology" because the rock strata are so easy to see. Sedimentary rocks are like a book that tells of the environment in which they formed. Rock units can be traced across large expanses. Looking down into the Grand Canyon, you get a sense of the vastness of space and of time.
The Hawaiian Islands from space.
The Hawaiian Islands are in the central Pacific Ocean, a land of sun, exotic life, and volcanoes. The islands increase in age from the Big Island of Hawaii at the southeast end of the chain through Maui, Kahoolawe, Lanai, Molokai, Oahu, Kauai, and Niihau Islands through the northwest. Kilauea volcano on Hawaii has been erupting almost continuously since 1983 and eruptions are also going on at an underwater volcano called Loihi seamount. Hawaii is a fantastic place to see volcanic eruptions and features.
- Earth scientists learn about many aspects of their disciplines by going out into the field.
- Field trips are an important part of the education of a geology student.
- The western United States is a great place to see examples of many types of geological phenomena.
Use this resources to answer the questions that follow.
Yosemite Nature Notes - Rockfall
1. What are run out zones?
2. What evidence is there for long term rockfalls having occurred?
3. How was Yosemite Valley created?
4. How did the rockfall in 2008 change the slope?
5. How can you determine the age of the boulder from a rockfall?
6. Why are they monitoring the mountains?
Our Changing Planet: Glacier National Park
7. What is happening to the glaciers in Glacier National Park?
8. How many glaciers are there in the park?
9. When do scientists predict that the glaciers will disappear?
FYI: Yellowstone Super Volcano
10. How large is Yellowstone?
11. What is Yellowstone?
12. How often has Yellowstone erupted in the past? What does this mean?
13. What heats the geysers and super volcano of Yellowstone?
14. How long did it take for the Grand Canyon to be formed?
15. What river runs through the Grand Canyon?
16. What is the youngest rock in the canyon?
17. What is found in the sandstone? What is this evidence of?
19. What is Vulcan's Throne?
20. Why are the faults important?
21. What is the evidence for long-term human habitation along the canyon?
22. Where does the Grand Canyon end?
How the Earth was Made: Hawaii
23. How many islands make up Hawaii?
24. How long has Kīlauea been continuously erupting?
25. Explain how Hawaii formed.
26. What is Hawaii?
1. How does the geography of Oregon parallel the geography of California?
2. Where are the arid lands in the western United States and why are they important for understanding geology?
3. How do the satellite images of the western United States give you a sense of space and time?