Lab 5 Assignment
docx
keyboard_arrow_up
School
Georgia State University *
*We aren’t endorsed by this school
Course
1113L
Subject
Geography
Date
Feb 20, 2024
Type
docx
Pages
6
Uploaded by CaptainIron11219
Lab 5: Weathering GEOG 1113L – Introduction to Landforms Lab
Name: I.
What is Weathering?
1.
What does weathering create/provide and what would Earth’s surface be composed of if weathering did not happen?
Weathering breaks down rocks and creates sediments which become the raw material for other rocks and for the formation of soil. Weathering is the principal source of inorganic material in soil, which vegetation needs to grow. provides Earth’s surface would be composed of solid bedrock if it weren’t for weathering.
2.
What is the difference between weathering and erosion?
Weathering preps the rock materials to be moved and erosion occurs when the rock is actually
moved.
3.
Describe the process of frost wedging (frost action).
Water absorbed into the pores within a rock expands when it frees, building up stress that causes the rock to break.
4.
Similar to frost wedging, Salt crystal growth
fractures rocks through crystal growth within the pores of the rock. These crystals originate from Water
inside the rock that later evaporates and leaves behind minerals
.
5.
The two previously mentioned types of weathering are both forms of what?
Mechanical weathering 6.
Which type of weathering causes metal to rust?
Oxidation, Chemical Weathering
7.
Weathering that alters minerals in a rock via water, oxygen, carbon, and/or other organic acids is called what?
Chemical Weathering
8.
Which type of weathering causes karst topography?
Chemical Weathering
9.
Name three features you might find in a karst landscape.
Sinkholes, caves, dry valleys
10.
What is one fact (from the video) about caves that you find interesting?
90% percent of possible caves are still undiscovered.
11.
Tree roots, lichen, and humans all play a part in weathering as well. Which type of weathering is this called?
Biological weathering
II.
Weathering Resistance
Use the two images below to answer questions about weathering resistance. Assume all rock layers in both images have been subjected to the same type/amount of weathering.
Image A:
1.
Which color/pattern represents a rock layer that is MOST resistant to weathering compared to the others?
Dark Gray
2.
Which color/pattern represents a rock layer that is LEAST resistant to weathering compared to the others?
Black
3.
Which colors/patterns represent rock layers that share the same level of resistance to weathering compared to the others?
Gray and light gray
Image B:
4.
Within the red box, which layer appears to be most resistant to weathering (A, B, or C)?
B
5.
Within the red box, which layer appears to be the least resistant to weathering?
C
6.
What is one indication that a rock layer is more resistant to weathering?
It is less broken down then others.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
III. Physical Vs. Chemical Weathering For each location below, be sure to explore the photo by dragging your mouse around the 360
o
view around you and using the scroll feature on your mouse to zoom in and out on specific parts of the image.
Answer each question that accompanies the link.
1.
Visit Apikuni Falls
in Glacier National Park. Some of these rocks have a white color, but they have an orange color where they are exposed to water from the waterfall. Which type of weathering is producing the orange-colored rocks? a.
Carbonation
b.
Oxidation
c.
Exfoliation
d.
Frost wedging
2.
Visit Stone Foundation
in Wisconsin. There is evidence in this 360
O
photo for which type of weathering? a.
Salt crystal growth
b.
Oxidation
c.
Exfoliation
d.
Frost wedging
3.
Visit Starved Rock State
Park in Illinois. What type of weathering do you see in this 360
O
photo? a.
Carbonation
b.
Oxidation
c.
Exfoliation
d.
Frost wedging
4.
Support your claim about the weathering in Starved Rock State Park with evidence you observe in the 360
O
photo. What type of weathering is this (chemical or physical)?
This is chemical weathering because its altering the minerals in the rock via water 5.
Differential weathering
means that some rocks breakdown more easily than others. For example,
in this picture
of a dolerite dike, you see a dark igneous rock forming a prominent low wall extending into the ocean. It sticks out above the beach sediment on either side of it (mostly sand) because the sand has formed from rocks that weathered away more easily. We consider the dolerite dike more resistant to weathering, because it resists weathering. Differential weathering in an outcropping of rock can produce dramatic landscapes. If a rock weathers easily, it will break down easily making gentle slopes. If a rock resists weathering, it will
make steep cliffs. Visit Monument Valley
in Arizona. Notice that the towers of rock are more resistant to weathering, while the gentle sided slopes at the bottom of the towers weather more
easily. Now visit LaSalle Canyon
at Starved Rock State Park in Illinois. The evidence of differential erosion is less obvious. Describe where in the LaSalle Canyon you see resistant or easily weathered layers. What evidence can you observe of differential weathering?
You can see resistance at the LaSalle Canyon through the steep cliffs. You can see easily weathered layers at the bottom where you see gentle slopes.
6.
One type of physical weathering not covered yet is abrasion
. A scratch on your skin or eye is called an abrasion and an “abrasive” person is someone that grates on your nerves. So, this form of weathering is just like it sounds. When sand or silt is picked up by water or wind and bumps into other rocks, it can round off the edges, making things smooth. River rocks are rounded because they roll around in rivers, bumping into one another and chipping off their rough edges. Sand carried by river water acts like sandpaper, smoothing the surface of the rocks. For example, see this photograph of rounded pebbles
. Abrasion also happens as a result of wind carrying sand. Visit Devil’s Garden
in Grand Staircase – Escalante National Monument in Utah. The towers of rock are called hoodoos. How are Devil’s garden hoodoos an example of differential weathering? Provide evidence from your observations of the 360
O
photo. There are a lot of layers in the rocks and some seem to be resisting more than others
.
7.
What evidence is there in the 360
O
photo of Devil’s Garden that the hoodoos and other rock outcrops were weathered by abrasion?
The rocks at the devil’s garden are all smooth. This is most likely due to the wind picking up sand from all around them.
IV. Karst Topography
Choose one of the five locations provided and visit the Google Earth link: 1. Central Kentucky Karst, USA
, 2. Sof Omar Cave, Ethiopia
, 3. Postojna Cave, Slovenia
, 4. Tenglong Cave, China
, 5. Waitomo Cave, New Zealand
.
Once you have chosen your location, utilize the following links to learn more about karst topography and answer the questions below. https://home.wgnhs.wisc.edu/wisconsin-geology/karst-sinkholes/
https://www.nps.gov/subjects/caves/karst-landscapes.htm
https://education.nationalgeographic.org/resource/karst/
https://people.uwec.edu/jolhm/Cave2006/Karst.html
https://www.gsi.ie/en-ie/programmes-and-projects/groundwater/activities/understanding-irish-karst/
karst-landforms/Pages/default.aspx
1.
What is one indication that the location you chose has karst topography? Take a screenshot of this feature (must be visible in the picture) and attach it below along with the name of the
feature. Tenglong Cave, China
There is a cave at this location which is a type of Karst topograpghy. This cave in particular has water running through it.
2.
The most common bedrock that makes up karst topography is what?
Carbonate Rocks
3.
What are two negative impacts of karst topography?
In developed areas, catastrophic sinkhole collapse can cause significant damage and loss of life.
Sink holes make building or living on karst topography very dangerous.
4.
What are three facts about karst topography from the provided links that you found interesting?
Karst topography areas are found in almost every part of the world but are most dynamic and most likely to occur in humid environments.
Karst is ideal for storing water as an aquifer and provides vast amounts
of clean drinking water to people, plants, and animals.
In Mexicos Yucatn Peninsula, you can find cenotes, which are karst sinkholes that have filled with water.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help