TIPS: Targeted Interventions for Proficiency in Science
Main Site »
RPDP Home
Contact Us
Tips Home
Middle School »
High School »
Earth Science

Content Benchmark E.8.C.5
home / earth science / earth's composition and structure /

Earth Science
Atmospheric Process and Water Cycle
Solar System and Universe
Earths Composition and Structure
  E.8.C.1
  E.8.C.2
  E.8.C.3
  E.8.C.4
  E.8.C.5
  E.8.C.6
  E.8.C.7
  E.8.C.8
Content Areas
Nature of Science (NOS)
Life Science
Earth Science
Physical Science

Students know geologic processes account for state and regional topography. E/S

Your family has decided to drive from Las Vegas to Reno, NV to see your mother's family. Another dreaded trip, you think. Your ecstatic mom says "This would be a great time to study the topography of Nevada. You know I did study science in college. "Oh boy, you think to yourself. What a treat, another long trip down the thruway looking at rocks. Your mother exclaims, "This trip will be great! I will teach you all about the geological processes of Nevada along the way! Get packing."

Nevada is among the most interesting states to study topography and the geologic processes that act on the crust of the "Silver State." Without a significant soil cover due to the Mojave Desert's climate, it makes it easier to study the geologic processes that make Nevada truly a geologist's paradise. With significant extinct volcanoes, plentiful canyons, and magnificent basin and range geology, Nevada boasts textbook geology that can be studied throughout the state.

Basin and Range Geology
Nevada, located near the western edge of the North American Plate, has experienced significant tectonic events throughout its history. Among the most visible expressions of this tectonic activity is the Basin and Range topography that covers most of Nevada and parts of the Southwestern US. The Basin and Range has been created by the stretching of Earth's crust, which has expanded the width of this area by 100%. As this region was stretched, it thinned out creating large faults. (See fault types below.) With a stretched out crust, normal faults have created the basin and range topography of the region. In Nevada, the basins and ranges are a result of normal faults which lie in a northeast - southwest trend. Basins, created by the down drop fault block, alternate between the ranges throughout the geophysical province. Figure 1a illustrates that normal faults are the primary cause of the Basin and Range geology of the desert southwest. The normal fault creates a break and movement in the crust forcing the left portion of the block upwards, whereas the right hand portion moves downward creating the basin. Alternative terminology for this type of faulting states that the upward fault block is known as the horst, and the downward block as the graben. The basin or graben will become a low elevation area where sediments will deposit creating a moderate elevation area. The northeast-southwest trend of the mountains and valleys are apparent in a digital elevation map shown in Figure 2.

Faulting
The solid rigid crust of Earth is broken into many large pieces called plates. Plates shift along the surface, as a result of plate tectonics, this shifting creates fractures in the crust. Faults are the result of tectonic forces, specifically, the movement of crust along the fracture.

Faults
Earth's crust is a rigid layer that fractures and faults creating many different topographic features such as mountain ranges, valleys and plateaus. Faults are the result of tectonic forces acting on the earth's crust. Three main types of faults (Figure 1a-c) are evident on Earth's surface and are categorized into three different types based on the processes that create the fault: Normal (extension), reverse (compression), and strike-slip (horizontal).

Normal Faults Normal faults are the result of crustal extension or tensional stress. Crustal extension occurs where the plates are moving away from a certain point, such as a plate boundary. The crust becomes stretched out, and a fracture develops into a normal fault. The remaining blocks of crust, known as the footwall (horst) and hanging wall (graben), are a result of the fault movement along the plane.


Figure 1a. A normal fault is a result of crustal extension,
or the stretching of Earth's crust.
(From http://facweb.bhc.edu/academics/science/harwoodr
/GEOL101/Study/Images/NormalFault.gif
)

Reverse or Thrust Faults
Reverse or thrust faults, are a result of tectonic forces that compress or shrink the crust. Reverse faulting can happen along plate boundaries or any where tectonic forces push the crustal plates against each other. This type of faulting causes the hanging wall to slide (up) past the footwall. A thrust fault is a reverse fault that has a low angle fault plane (close to the horizontal), whereas a reverse fault has a very high angle fault plane (closer to the vertical).


Figure 1b. A reverse fault is where the hanging wall moves
up along the fault plane relative to the footwall block.
(From http://facweb.bhc.edu/academics/science/
harwoodr/Geol101/study/Images/ReverseFault.gif
)

Strike-Slip Faults
Strike-slip faults are a result of horizontal movement of Earth's crust. Tectonic forces act on the crust causing one block of crust to move in the opposite direction of the other block of crust. The result of these faults is localized earthquakes along the fault plane. The most familiar area in the world where a strike-slip fault is occurring is the San Andreas Fault in California. Where the coast of southern California is moving basically northward in comparison to the inland/continental portion of California, eventually the city of Los Angeles will slide northwestward and end up near the San Francisco Bay.


Figure 1c. A strike-slip fault is the result of horizontal movement of Earth's crust resulting in the offset of two blocks of crust.
(From http://facweb.bhc.edu/academics/science/
harwoodr/Geol101/study/Images/StrikeSlipRLFault.gif


Figure 2. The Basin and Range topography and the north-south trending alternating mountains and valleys are illustrated in this digital elevation map of Nevada.
(From http://www.seismo.unr.edu/graphics/Maps/nv-topo.jpg)

To learn more about Basin and Range geology and other important physiographic provinces of North America, go to http://wrgis.wr.usgs.gov/parks/province/basinrange.html

Canyons
Canyons are a prominent geologic feature, particularly in the desert southwest. Canyons are a deep valley between steep sided cliffs, while most canyons are developed primarily by a river that erodes through less resistant rock. Weathering acts further upon the canyon to wear down the walls and widen the canyon, although minimal weathering exists in canyons in the southwest. Among the more famous canyons of the world is the Grand Canyon, Arizona, which has been eroded by the Colorado River, mostly over the past 6 million years. Figure 3 represents the multiple layers of strata that the Colorado River erodes into a v-shape incision.


Figure 3. The Grand Canyon strata have been eroded into a v-shaped river over the past 6 million years by the Colorado River.
(From http://www.answersingenesis.org/creation
/images/v27/i3/canyon_fig2.jpg
)

To read more about the Grand Canyon, go to
http://geology.com/articles/age-of-the-grand-canyon.shtml

Alluvial Fans
Alluvial fans are a common landform in Nevada as they are a primary result of flash flooding, or water erosion in the mountains. Alluvial fans are sediment and debris deposits that form in a fan shape as floods and gravity carry debris down slope. The distance the material, or alluvium travels through the canyon and down slope is related to the carrying capacity of the flood water. If a higher energy flow moves through the canyon, the alluvium will be carried further than if a lower energy flow moves through the canyon. Also, the higher the energy of the flow, the larger the size of objects moved will be, slow moving water may only carry pebbles and silt, fast moving water may move boulders. Figure 4 shows the fan shape of the deposit and subsequent water channels in the foreground of the picture. In the background of the picture, the canyon splits the mountain into two portions.


Figure 4. Alluvial fans are a common feature of Nevada, known as one of the most mountainous states in the US.
(From http://lang.sbsun.com/projects/fireflood/graphics/alluvialfan.gif)

To view images of alluvial fans in the United States, see http://www.uoregon.edu/~millerm/fan.html.

To read more about alluvial fans in Death Valley National Park, CA, go to http://wrgis.wr.usgs.gov/parks/deva/rfan.html

Volcanoes
Volcanoes are an integral part of the geologic history of the state. Figure 5 defines the sites of major volcanic activity for the state of NV. Most volcanic activity outlined in the map is the result of extensional forces on the crust resulting in the upwelling of magma. These volcanoes are quite young, geologically, and they have been active in the Cenozoic Era, from 65 million years ago to present. The volcanoes of Nevada are mostly cinder cones, or smaller calderas.


Figure 5. A map displaying the major volcanic areas of Nevada. Courtesy of the USGS.
(From http://vulcan.wr.usgs.gov/Volcanoes/
Nevada/Maps/map_nevada_volcanics.html
)

Volcanoes are an opening or a rupture in the crust of the Earth. These openings are a result of tectonic forces and are found mostly in convergent and divergent zones of crustal activity. Volcanoes are classified as being active, dormant, or extinct. An active volcano is one that is currently erupting or one that is showing signs of erupting. Dormant volcanoes have the potential to erupt, while extinct volcanoes are unlikely to erupt ever again. Supervolcanoes, like Yellowstone NP, are the exception of this classification, as they are calderas, which erupt between long periods of time. The last eruption was approximately 640,000 years ago and scientist date the caldera at 2 million years old. Caldera formation is illustrated in Figure 7, where a volcano erupts and the overlying pressure, or weight of rock topples into the center of the volcano leaving a crater like depression in the volcanic area.


Figure 6. A typical volcano diagram showing major components of an active volcano.
(From http://usscouts.org/bbugle/bb0701/bb0701_files/image045.jpg)


Figure 7. Caldera formation illustrating the collapse of overlying rock.
(From http://usscouts.org/bbugle/bb0701/bb0701_files/image045.jpg)

View interesting caldera pictures from around the world, and learn more about caldera formation, by visiting http://vulcan.wr.usgs.gov/Glossary/Caldera/description_caldera.html

back to top


Content Benchmark E.8.C.5

Students know how geologic processes account for state and regional topography. E/S

Common misconceptions associated with this benchmark


1. Students may believe that earthquakes cause volcanic eruptions.

A commonly held misconception among students is that earthquakes cause volcanic eruptions around the world. Although they are often related, as they are both significant geological events that produce great change, neither event has been directly linked as a cause or effect of the other. Often, students will look at a map, particularly looking at the Ring of Fire in the Pacific Ocean and see that earthquake and volcano locations are close in distance. Although, the scale of the map may place them very close to each other, they may be hundreds of miles apart. Secondly, students believe that earthquakes in the crust of Earth will cause fractures in the crust where mantle magma will rise up, which would actually occur very infrequently.

Although scientists are unsure of the evidence of the relationship of earthquakes and volcanoes, you may visit the United States Geological Survey - Volcanic Hazards site to read more about this important geological activity. Access this information at http://volcanoes.usgs.gov/Products/FAQs/FAQ_EQ+Volc.html


2. Students incorrectly think that Nevada doesn't have volcanoes.

Volcanoes are a common geologic feature of topography located near plate boundaries. Not long ago, geologically speaking, Nevada was located near the active western edge of the North American plate where fractures and faults in the crust allowed magma to rise up to the crust and create frequent volcanic activity. This has resulted in volcanoes located in Nevada which have erupted within the Cenozoic Era, lasting from 65 million years ago to present. These eruptions have produced volcanic flows of mainly basalt rocks.

Evidence of volcanoes in Nevada are provided in a geological map by the Nevada Bureau of Mines, located at http://www.nbmg.unr.edu/dox/e30.pdf


3. Students may incorrectly believe that plate tectonics causes topographic features, such as mountains, to form very quickly.

A commonly held misconception is that students believe that mountains develop very quickly. Geologically, mountains can develop quickly, in the form of volcanic activity, but most mountains are created by the folding and faulting of Earth's crust. Most movement of Earth's crust happens at a very slow rate, as geologists' measure the movement of Earth's crust in inches per year. Infrequently, an event will occur, like the 9.0 magnitude earthquake in the Indian Ocean of 2004, where the crust shifted approximately 20 meters, displacing ocean water creating a devastating tsunami that took the toll of more than 250,000 lives off the coast of Northern Sumatra in the Indian Ocean.

Mt. Everest, the result of convergent-convergent plate boundaries, is a mountain that is continuously increasing in height. Approximately 50 million years ago, the landmasses of Eurasia and India have collided and have risen up to create the Himalaya Mountains, the tallest mountain range in the world.

To understand the dynamics of plate tectonics, go to an excellent publication by the USGS at http://pubs.usgs.gov/gip/dynamic/dynamic.pdf


4. Students incorrectly think that Nevada doesn't have earthquakes.

Nevada is among the most active states in regards to the number of earthquakes. Due to Nevada's proximity to the San Andreas Fault, and numerous faults in the crust of Nevada, this state ranks among the highest in the number of major earthquakes experienced. Although, the major cities of Las Vegas and Reno haven't experienced a large earthquake (magnitude 5.0 and greater), the state of Nevada experiences many smaller earthquakes.

To learn more about Nevada and earthquakes, the University of Nevada at Reno has an informative website on earthquakes for over 100 years. See http://www.seismo.unr.edu

To view a map of tectonic features and faults in Clark County, NV, go to http://www.nbmg.unr.edu/dox/b62/B62%20Plates/B62%20PLATE%205.pdf

back to top


Content Benchmark E.8.C.5
Students know how geologic processes account for state and regional topography. E/S

Sample Test Questions

1st Item Specification: Students know how geologic processes account for local and state topography.

Depth of Knowledge Level 1

  1. Which of the following is a landform created by two tectonic plates converging?
    1. Playa
    2. Mountain
    3. Plateau
    4. Valley
  1. The Basin and Range topography of Nevada is recognized for
    1. volcanoes and rivers.
    2. valleys and mountains.
    3. volcanoes and earthquakes.
    4. alleys and earthquakes.

Depth of Knowledge Level 2

  1. How is the geologic process of creating canyons and mountains different? Canyons are made by
    1. faulting and mountains are created by erosion.
    2. erosion and mountains are created by erosion.
    3. erosion and mountains are made by folding.
    4. faulting and mountains are made by folding.
  1. Which geologic process is most responsible for the formation of extinct volcanic   mountains in Nevada’s geologic history?
    1. Crust strecthing and magma upwelling
    2. Crust compression
    3. Weathering and erosion
    4. Metamorphism of rock around a magma chamber


2nd Item Specification: Recognize and compare geologic processes that shape Nevada’s regions.

Depth of Knowledge Level 1

  1. Use the map below showing the mountainous topograpy of Nevada to answer the question that follows.


 (From http://www.seismo.unr.edu/graphics/Maps/nv-topo.jpg)

  1. The orientation or direction of the majority of mountains in Nevada is
    1. northwest – southeast.
    2. east – west.
    3. south-southwest.
    4. northeast – southwest.
  1. Use the map below showing the recent earthquakes in California and Nevada to answer the question that follows.


(From http://quake.usgs.gov/recenteqs/)

  1. Which area has the highest frequency of earthquakes?
    1. Northern California
    2. Southern Nevada
    3. Northern Nevada
    4. Southern California
  1. Answer the following question using the diagram below.


(From: http://facweb.bhc.edu/academics/science/harwoodr/
GEOL101/Study/Images/NormalFault.gif
)

  1. What type of fault is a result of horizontal movement in an opposite direction along the Earth’s crust?
    1. Block
    2. Normal
    3. Strike-Slip
    4. Reverse
  1. Answer the following question using the diagram below.


(From: http://facweb.bhc.edu/academics/science/
harwoodr /GEOL101/Study/Images/NormalFault.gif
)

  1. What type of fault is a result of horizontal movement away from the fault line?
    1. Block
    2. Normal
    3. Strike-Slip
    4. Reverse


Depth of Knowledge Level 2

  1. Which of the following landforms in Nevada are classified as a result of erosion?
    1. canyon and mountain
    2. alluvial fan and canyon
    3. mountain and volcano
    4. alluvial fan and mountain


Constructed Response E.8.C.5

1. Answer the following questions using the diagram below.


(From: http://jan.ucc.nau.edu/~rcb7/Grand_Staircase.jpg)

  1. Identify a process of erosion that helps to shape the Grand Staircase.
  2. Explain the difference between erosion and weathering and how each process acts on the Grand Staircase.
  3. Describe why the Navajo Sandstone (Ss) would erode slower than the Tropic Shale (Sh).

back to top


Content Benchmark E.8.C.5

Students know how geologic processes account for state and regional topography. E/S Relate geological processes to certain topographical features (e.g. basin and range, canyon, alluvial fans, and volcanoes)

Answers to Sample Test Questions

  1. B, DOK Level 1
  2. B, DOK Level 1
  3. C, DOK Level 2
  4. A, DOK Level 2
  5. D, DOK Level 1
  6. D, DOK Level 1
  7. C, DOK Level 1
  8. B, DOK Level 1
  9. B, DOK Level 2


Constructed Response E.8.C.5 Score Rubric:

3 points

Response addresses all parts of the question clearly and correctly.

  1. Erosion of the Grand Staircase can occur by water, wind, and gravity.
  2. Erosion is the movement of rocks whereas weathering is the breakdown of rocks. Each acts on the Grand Staircase by breaking rocks down into sediment and moving them.
  3. Sandstone is resistant to weathering and erosion because it is composed mostly of quartz, a rather hard mineral. Tropic shale breaks down easily due its composition and therefore would be eroded faster than the Navajo Sandstone.

2 points

Response addresses all parts of the question and includes only minor errors.

1 point

Response does not address all parts of the question.

0 points

Response is totally incorrect or no response provided.


back to top


Content Benchmark E.8.C.5

Students know how geologic processes account for state and regional topography. E/S

Intervention Strategies and Resources

The following is a list of intervention strategies and resources that will facilitate student understanding of this benchmark.

1. Volcanoes!

Volcanoes! is an interdisciplinary set of materials for grades 4-8. Through the story of the 1980 eruption of Mount St. Helens, students will answer fundamental questions about volcanoes. The teaching packet reflects the goals of the National Science Education Standards developed by the National Research Council and incorporates a number of related subjects, including other sciences, social studies, language arts, and mathematics.

To access this lesson guide, go to
http://erg.usgs.gov/isb/pubs/teachers-packets/volcanoes/


2. Image Gallery of Landforms

The National Aeronautics and Space Administration (NASA) have provided a comprehensive guide to landforms in this visual guide. This is a valuable resource to display to students who are unfamiliar with most landforms in Nevada and outside the area. A link is provided for student activities to further enhance the lesson.

To visit this website, go to http://daac.gsfc.nasa.gov/geomorphology/GEO_COMPLETE_TOC.shtml


3. Mojave Desert Landforms

An excellent resource for teachers who want to learn more about the Mojave Desert, this geological guide provides in-depth research and spectacular pictures. Each chapter of this guide provides an approachable understanding of the climate and geological processes that shape the Mojave Desert.

To access this website guide, go to http://pubs.usgs.gov/of/2004/1007/


4. Hydrology and Landforms

This exciting lesson from the Northeast Ohio Geoscience Teachers and Kent State University brings hands on activities to the classroom in a clear and informative lesson for grades 3 -12. Students have the opportunity to examine satellite photos, model wind and water erosion and recognize local landforms. Facilitators can use this lesson plan over a few days or during a block period to maximize learning.

To access this lesson plan, go to http://neogeo.kent.edu/activities/NEOGEO-hydrology%20and%20landforms.pdf


5. Landforms and Topographic Map Assessment

An easy and effective module, it provides students the opportunity to view landforms on topographic maps. Each slide provides a separate map and feature. At the completion of the module, students need to match the appropriate map to the landform feature. This module is an excellent method to review difficult topographic and landform relationships.

To access this website, go to http://rockyweb.cr.usgs.gov/outreach/topofeaturequiz.pdf


back to top

Benchmark
Support Pages

Misconceptions:
Click Here
Sample Questions:
Click Here

Intervention Strategies & Resources:
Click Here

Benchmark Related Vocabulary

Desert
Geology
Landform
Mountain
Plate boundary
Plate tectonic
Plateau
Sierra Nevada Mountains
Topography
Valley