Photograph of badlands in Theodore Roosevelt National Park, North Dakota. The photo shows rounded hills with sparse vegetation made up of trees and shrubs. The exposed rock is mostly tan, with some bands of white, orange, and dark brown.  

Additional Resources for the Earth Science of the Northwest-central United States

Page snapshot: Lists of supplemental and teaching resources for the geology of the northwest-central U.S., sorted by topic.


Topics covered on this page: Geologic history; Rocks; Fossils; Topography; Mineral resources; Glaciers; Energy; Climate; Earth hazards.

Credits: Most of the resources from this page come from the The Teacher-Friendly Guide to the Earth Science of the Northwest-central US, edited by Mark D. Lucas, Robert M. Ross, and Andrielle N. Swaby (published in 2015 by the Paleontological Research Institution). The book was adapted for the web by Elizabeth J. Hermsen and Jonathan R. Hendricks in 2022.

Updates: Page last updated August 22, 2022.

Image above: Badlands in the Painted Canyon, Theodore Roosevelt National Park, North Dakota. Photo by Acroterion (Wikimedia Commons, Creative Commons Attribution-ShareAlike 4.0 International license, image cropped and resized).

Disclaimer: Links to commercial websites (internet retailers, rock and mineral shops, informational websites that include a shop, etc.) do not constitute endorsement of their products.

Geologic history

Books, articles, and reports

Blakey, R. C., and W. D. Ranney (eds.). 2018. Ancient landscapes of western North America: A geologic history with paleogeographic maps. Springer Nature, Switzerland.

Bluemle, J. 2016. North Dakota's geologic legacy: Our land and how it formed. North Dakota State University Press, 450 pp.

Love, D., J. C. Reed, Jr., and K. L. Pierce. 2003. Creation of the Teton Landscape, 2nd revised and enlarged edition. Grand Teton Association, Moose, Wyoming, 135 pp. The original 1971 edition by D. Love and J. C. Reed, Jr., is online in full: https://www.nps.gov/parkhistory/online_books/grte/grte_geology/index.htm

Roehler, H. W. 1992. Introduction to greater Green River basin geology, physiography, and history of investigations. U.S. Geological Survey Professional Paper 1506-A, 14 pp. PDF: https://doi.org/10.3133/pp1506A

Trimble, D. E. 1980. The geologic story of the Great Plains: a nontechnical description of the origin and evolution of the landscape of the Great Plains. US Geological Survey Bulletin 1493. PDF: https://doi.org/10.3133/b1493 (Also available on Project Gutenburg in multiple formats: https://www.gutenberg.org/ebooks/63396)

Websites

North Dakota Geology (John Bluemle, Ph.D.): http://johnbluemle.com/

Rocks

General/multiple states

Martin, J., and J. H. Monaco. 2007. Fee mining and rockhounding adventures in the West, 2nd ed. Gem Guides Book Company, Baldwin Park, California, 240 pp.

Romaine, G. 2014. Rocks, gems, and minerals of the Rocky Mountains. FalconGuides, Guilford, Connecticut, 176 pp.

Romaine, G. 2020. Rocks, gems, and minerals of the Rocky Mountains, 2nd ed. FalconGuides, Guilford, Connecticut, 176 pp.

Idaho

Books, articles, and reports

Romaine, G. 2010. Rockhounding Idaho: A guide to 99 of the state's best rockhounding sites. FalconGuides, Guilford, Connecticut, 264 pp.

Books, articles, and reports

Rocks of Idaho (Digital Atlas of Idaho, page by J. Harvey, V. Taube, and D. Boyack): https://digitalatlas.cose.isu.edu/geo/rocks/rocks.htm

Montana

Hodges, M., and R. Feldman. 2006. Rockhounding Montana (2nd edition): A guide to 91 of Montana's best rockhounding sites. FalconGuides, Guilford, Connecticut, 232 pp.

Wyoming

Graham, K. L. 1996. Rockhounding Wyoming. Falcon Press Publishing Company (A Falcon Guide), Helena, Montana, 168 pp.

Graham, K. L. 2017. Rockhounding Wyoming: A guide to the state's bets rockhounding sites, 2nd ed. FalconGuides, Guilford, Connecticut, 256 pp.

Hausel, W. D. 2009. Gems, minerals & rocks of Wyoming: A guide for rock hounds, prospectors & collectors. W. Dan Hausel Geological Consulting LLC, Gilbert, Arizona, 176 pp.

Fossils

General/multiple states

Books, articles, and reports

Cvancara, A. M. 1966. Revision of the fauna of the Cannonball Formation (Paleocene) of North and South Dakota, Part 1, Bivalvia. Contributions from the Museum of Paleontology, University of Michigan, 20(10): 1–97. [Technical.]

Cvancara, A. M., and J. W. Hoganson. 1993. Vertebrates of the Cannonball Formation (Paleocene) in North and South Dakota. Journal of Vertebrate Paleontology, 13(1): 1–23. [Technical.] https://doi.org/10.1080/02724634.1993.10011484

Foster, J. 2007. Jurassic West: The dinosaurs of the Morrison Formation and their world. Indiana University Press, Bloomington.

Hagadorn, J. W. 2002. Bear Gulch: An exceptional upper Carboniferous plattenkalk. In: D. J. Bottjer, W. Etter, J. W. Hagadorn, and C. M. Tang, eds., Exceptional fossil preservation: a unique view on the evolution of marine life. Columbia University Press, New York, pp. 167–183. [Technical.]

Johnson, K. 2007. Cruisin’ the fossil freeway: An epoch tale of a scientist and an artist on the ultimate 5,000-mile paleo road trip. Fulcrum Publishing, Golden, Colorado, 208 pp. [illustrated by Ray Troll]

Larson, N. L., S. D. Jorgensen, R. A. Farrar, and P. L. Larson. 1997. Ammonites and the other cephalopods of the Pierre Seaway. Geoscience Press, Tucson, Arizona, 148 pp.

Lockley, M. G., and A. P. Hunt. 1995. Dinosaur tracks and other fossil footprints of the western United States. Columbia University Press, New York.

Martin, J. E., and D. C. Parris, eds. 2007. The geology and paleontology of the Late Cretaceous marine deposits of the Dakotas. Geological Society of America Special Paper 427, 256 pp. [Technical.] https://doi.org/10.1130/SPE427

Tidwell, W. D. 1998. Common fossil plants of western North America, second edition. Smithsonian Institution Press, Washington, DC. [Covers western states of contiguous U.S. and southern Alberta, British Columbia, and Saskatchewan in Canada.]

Websites

Websites from the Paleontological Research Institution & partners:

Cretaceous Atlas of Ancient Life, Western Interior Seaway (Colorado, Iowa, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, Utah, Wyoming): https://www.cretaceousatlas.org/geology/

Pennsylvanian Atlas of Ancient Life, Midcontinent United States (Iowa, Illinois, Indiana, Kansas, Missouri, Nebraska, Oklahoma, Texas): https://pennsylvanianatlas.org/

Idaho

Books, articles, and reports

Rember, B. 2010. Lake Clarkia fossil sites. Sage Notes 32(1): 1-3. PDF available from the Idaho Native Plant Society: https://idahonativeplants.org/news/SageNotesFeb2010.pdf

Ross, S. H., and C. N. Savage. 1967. Idaho Earth science: Geology, fossils, climate, water, and soils. Idaho Bureau of Mines and Geology (Earth Science Series 1), Boise, Idaho, 271 pp. PDF download from Idaho Geological survey: https://www.idahogeology.org/product/E-1

Smiley, C. J., ed. 1985. Late Cenozoic history of the Pacific Northwest: Interdisciplinary studies on the Clarkia Fossil Beds of northern Idaho. Pacific Division of the American Association for the Advancement of Science/California Academy of Sciences, San Francisco, CA, 417 pp. [Technical.]

Steinthorsdottir, M., and H. K. Coxall. 2019. Clarkia flora: 16-million-year-old plants offer a window into the past. Deposits Mag, November 3, 2019. https://depositsmag.com/2019/03/11/the-clarkia-flora-16-million-year-old-plants-offer-a-window-into-the-past/

Websites

Fossils in Idaho (Digital Atlas of Idaho): https://digitalatlas.cose.isu.edu/geo/fossils/fossils.htm

Hagerman Fossil Beds National Monument: https://www.nps.gov/hafo/index.htm

Montana

Books, articles, and reports

Horner, J. R. 2001. Dinosaurs under the big sky. Mountain Publishing, Missoula, Montana, 195 pp.

Hunt, R.K. 2006. Middle Proterozoic paleontology of the Belt Supergroup, Glacier National Park, In: S. G. Lucas, J. A. Spielmann, P. M. Hester, J. P. Kenworthy, and V. I. Santucci (eds), Fossils from federal lands, New Mexico Museum of Natural History and Science Bulletin 34, pp. 57–62. 

Wilson, G. P., W. A. Clemens, J. R. Horner, and J. Hartman, eds. 2014. Through the end of the Cretaceous in the type locality of the Hell Creek Formation in Montana and adjacent areas. Geological Society of America Special Paper 503, 392 pp. https://doi.org/10.1130/SPE503

Websites

Egg Mountain, the Two Medicine, and the caring mother dinosaur (National Park Service): https://www.nps.gov/articles/mesozoic-egg-mountain-dawson-2014.htm

Paleontology - Egg Mountain (by Willie Freimuth on The Montana Geoheritage Project, SERC): https://serc.carleton.edu/research_education/mt_geoheritage/sites/augusta_choteau/paleontology.html

University of Montana Paleontology Center: https://hs.umt.edu/paleo/default.php

Nebraska

Books, articles, and reports

1980. Agate Fossil Beds. National Park Service Handbook 107, Washington, DC, 95 pp. Available online via Project Gutenburg: https://www.gutenberg.org/files/56303/56303-h/56303-h.htm

Pabian, R. K. 1970. Record in rock: a handbook of the invertebrate fossils of Nebraska. University of Nebraska Conservation and Survey Division Educational Circular 1, 99 pp. PDF download: https://digitalcommons.unl.edu/conservationsurvey/1

Tucker, S. T., R. E. Otto, R. M. Loeckel, and M. R. Voorhies. 2014. The geology and paleontology of Ashfall Fossil Beds, a late Miocene (Clarendonian) mass-death assemblage, Antelope County and adjacent Knox County, Nebraska, USA, In: J. T. Korus, ed., Geologic field trips along the boundary between the Central Lowlands and Great Plains. Geological Society of America Field Guide 36, 22 pp. https://doi.org/10.1130/2014.0036(01)

Voorhies, M. R., J. R. Bozell, G. F. Carlson, and J. Ludwickson. 1994. The cellars of time: paleontology and archeology in Nebraska. Nebraskaland Magazine (Nebraska Game and Parks Commission), 72(1), 162 pp.

Websites

Agate Fossil Beds National Monument: https://www.nps.gov/agfo/index.htm

University of Nebraska State Museum: Ashfall Fossil Beds: https://ashfall.unl.edu/

North Dakota

Websites

Paleontology (North Dakota Mineral Resources): https://www.dmr.nd.gov/dmr/paleontology

South Dakota

Books, articles, and reports

Benton, R. C., D. O. Terry, Jr., E. Evanoff, and H. G. McDonald. 2015. The White River Badlands: Geology and paleontology. Indiana University Press, Bloomington, Indiana, 240 pp.

Feldmann, R. M., and R. A. Heimlich. 1980. The Black Hills Field Guide. Kendall/Hunt Publishing Company, Dubuque, Iowa, 190 pp.

O’Harra, C. C. 1920. The White River Badlands. South Dakota School of Mines Bulletin 13: 181 pp., 96 pls. PDF: http://npshistory.com/publications/badl/sdsm-13.pdf

Santucci, V. L., and J. Ghist. 2014. Fossil Cycad National Monument: A history from discovery to deauthorization. Dakoterra 6: 82–93. PDF: https://irma.nps.gov/DataStore/DownloadFile/639954

Websites

Badlands National Park: https://www.nps.gov/badl/index.htm

Fossil Cycad National Monument (by V. Santucci and C. Knight, National Park Service): https://www.nps.gov/articles/fossil-cycad-national-monument.htm

The Fossils of the White River Badlands (website by Ryan C.): https://whiteriver.weebly.com/

The Mammoth Site (Hot Springs, South Dakota): https://www.mammothsite.org/

SUE the T. rex (Field Museum of Natural History blog): https://www.fieldmuseum.org/blog/sue-t-rex

Wyoming

Books, articles, and reports

Boyd, D. W., and D. R. Lageson. 2014. Self-guided walking tour of Paleoproterozoic stromatolites in the Medicine Bow Mountains, Wyoming. Wyoming State Geological Survey Public Information Circular 45, 26 pp. https://www.wsgs.wyo.gov/products/wsgs-2014-pic-45. PDF: https://www.wsgs.wyo.gov/products/wsgs-2014-pic-45.pdf

Grande, L.. 2013. The lost world of Fossil Lake: Snapshots from deep time. University of Chicago Press, Chicago, Illinois. [Covers the geology and fossils of the Eocene Green River Formation in Colorado, Utah, and Wyoming, with a special emphasis on Fossil Lake in Wyoming.]

Hager, M. W. 1970. Fossils of Wyoming. Wyoming Geological Survey, Laramie, Wyoming, 51 pp. Download from Figshare: https://figshare.com/articles/figure/Fossils_of_Wyoming/13693201/3

Lowe, S. 2014. The world's oldest building: The Fossil Cabin at Como Bluff. WyoHistory.org, November 8, 2014. https://www.wyohistory.org/encyclopedia/fossil-cabin

Websites

Como Bluff and "The Bone Wars," (Cultural Geology Guide, Wyoming State Geological Survey): https://www.wsgs.wyo.gov/public-info/guide-como-bluff

Fossil Butte National Monument: https://www.nps.gov/fobu/index.htm

Paleontology (Wyoming State Geological Survey): https://www.wsgs.wyo.gov/wyoming-geology/paleontology.aspx

Topography

Books, articles, and reports

Trimble, D. E. 1980. The geologic story of the Great Plains. US Geological Survey Bulletin 1493. https://doi.org/10.3133/b1493

Websites

No ordinary plain: North Dakota’s physiography and landforms (North Dakota Geological Survey Notes 1, 2007, by John Bluemle and Bob Biek): https://www.dmr.nd.gov/ndgs/ndnotes/ndn1.asp

North Dakota’s mountainous areas: The Killdeer Mountains and the Turtle Mountains (North Dakota Geological Survey Notes 15, 2002, by John Bluemle): https://www.dmr.nd.gov/ndgs/ndnotes/ndn15.asp

The Origin of Landscape: A Guide to Wyoming’s Cultural Geology (Cultural Geology Guide, Wyoming State Geological Survey): https://www.wsgs.wyo.gov/public-info/cultural-geology

Mineral resources

Books, articles, and reports

Beckwith, J. A. 1972. Gem minerals of Idaho. Caxton Printers, Caldwell, Idaho, 129 pp.

Hausel, W. D. 2009. Gems, minerals & rocks of Wyoming: A guide for rock hounds, prospectors & collectors. W. Dan Hausel Geological Consulting LLC, Gilbert, Arizona, 176 pp.

Hausel, W. D., and E. J. Hausel. 2011. Gold: A field guide for prospectors and geologists (Wyoming and nearby regions). Dan Hausel Geological Consulting, Gilbert, Arizona, 366 pp.

Ream, L. 2012. Gem trails of Idaho & western Montana. Gem Guide Books, Upland, California, 256 pp.

Rygle, K. J. 2011. Northwest treasure hunter's gem & mineral guide: Where & how to dig, pan and mine your own gems & minerals, 5th ed. GemStone Press, Woodstock, Vermnot, 200 pp.

Wilson, Anna B., and Ed DeWitt. 1995. Maps showing metallic mineral districts and mines in the Black Hills, South Dakota and Wyoming. U.S. Geological Survey Miscellaneous Investigations Series, Map I-2455, 72 pp., 1 map. https://doi.org/10.3133/i2445

Websites

Gold in North Dakota (North Dakota Geological Survey Notes 6 by John Bluemle): https://www.dmr.nd.gov/ndgs/ndnotes/ndn6.asp

Western Mining History: https://www.westernmininghistory.com/

Glaciers

Books, articles, and reports

Ahlbrandt, T. S., and S. G. Fryberger. 1980. Geologic and paleoecologic studies of the Nebraska Sand Hills, Eolian deposits in the Nebraska Sand Hills, US Geological Survey Professional Paper 1120-A-C, 58 pp. https://doi.org/10.3133/pp1120AC

USGS. Retreat of Glaciers in Glacier National Park [Montana]. http://npshistory.com/publications/glac/glacier-retreat-2017.pdf

Websites

Eolian landforms and deposits of the Eastern Snake River Plain, Idaho (by W. M. Phillips, Vignettes: Key Concepts in Geomorphology): https://serc.carleton.edu/vignettes/collection/36639.html

Explore glacial Lake Missoula (Montana Natural History Center): https://www.montananaturalist.org/exhibits/explore-glacial-lake-missoula/

Glaciation (by W. J. Wayne in Encyclopedia of the Great Plains): http://plainshumanities.unl.edu/encyclopedia/doc/egp.pe.029

Glacial Lake Agassiz (North Dakota Geological Survey Notes 5 by John Bluemle): https://www.dmr.nd.gov/ndgs/ndnotes/Agassiz/

Glaciers of the America West (Departments of Geology and Geography, Portland State University, Portland, Oregon): https://glaciers.us/ [Includes coverage of glaciers in Idaho, Montana, and Wyoming.]

Glaciers of Idaho (by C. Cannon, 2011, in Glaciers of the American West): https://glaciers.us/glaciers.research.pdx.edu/glaciers-idaho-2.html

Glaciers of Montana (by A.G. Fountain, 2011, in Glaciers of the American West): https://glaciers.us/glaciers.research.pdx.edu/glaciers-montana-2.html

Glaciers of Wyoming (by M. Devisser, 2011, in Glaciers of the American West): https://glaciers.us/glaciers.research.pdx.edu/glaciers-wyoming-2.html

Mystery of the megaflood (NOVA, PBS): https://www.pbs.org/wgbh/nova/megaflood/

Repeat Photography Project (Northern Rocky Mountain Science Center, USGS): https://www.usgs.gov/centers/norock/science/repeat-photography-project

Energy

General/multiple states

Books, articles, and reports

Hanson, J. L., and P. Limerick. 2009. What every westerner should know about oil shale. Report from the Center #10, Center of the American West, University of Colorado at Boulder. PDF: https://calisphere.org/item/ark:/86086/n2zk5frn/

Hartman, J. H., B. Roth, and A. J. Kihm. 1997. Deposition of lignites in the Fort Union Group and related strata of the Northern Great Plains. University of North Dakota, Energy and Environmental Research Center, Grand Forks, North Dakota, 31 pp. https://digital.library.unt.edu/ark:/67531/metadc693470/

Luppens, J. A., D. C. Scott, J. E. Haacke, L. M. Osmonson, and P. E. Pierce. 2015. Coal geology and assessment of coal resources and reserves in the Powder River Basin, Wyoming and Montana. U.S. Geological Survey Professional Paper 1809, 218 pp. https://doi.org/10.3133/pp1809

Idaho

Websites

Energy Sources (Idaho Governor's Office of Energy and Mineral Resources): https://oemr.idaho.gov/sources/

Montana

Books, articles, and reports

Gunderson, J. A., and J. Wheaton. Coal resources of Montana. Montana Bureau of Mines and Geology Special Publication 122: Geology of Montana, vol. 2, Special Topics, 27 pp. PDF: https://mbmg.mtech.edu/pdf/geologyvolume/Gunderson_CoalGeologyFInal.pdf

Websites

Wind energy in Montana (Montana State University): https://www.montana.edu/wind/windinmontana.html

Nebraska

Websites

Energy resources (Nebraska Public Power District): https://www.nppd.com/powering-nebraska/energy-resources?locale=en

North Dakota

Websites

Energy: Powered by North Dakota (North Dakota Studies): https://www.ndstudies.gov/energy/level1/

Mineral Resources of North Dakota: Coal (by Ed Murphy, Department of Mineral Resources, North Dakota Geological Survey): https://www.dmr.nd.gov/ndgs/mineral/nd_coalnew.asp

South Dakota

Websites

Energy (South Dakota Public Utilities Commission): https://puc.sd.gov/energy/default.aspx

Wyoming

Websites

Wyoming Energy Authority: https://www.wyoenergy.org/

Wyoming's energy resources (Wyoming State Geological Survey): https://www.wsgs.wyo.gov/energy/energy.aspx

Climate

Books, articles, and reports

1998. Climate Change and Idaho. Environmental Protection Agency EPA 236-F-98-007f, September 1998, 4 pp. https://nepis.epa.gov/Exe/ZyPDF.cgi/40000PRA.PDF?Dockey=40000PRA.PDF

2005. Changes in streamflow timing in the western United States in recent decades. U.S. Geological Survey Factsheet 2005-3018, March 2005, 4 pp. https://pubs.usgs.gov/fs/2005/3018/#pdf

Fischetti, M. 2015. U.S. droughts will be the worst in 1,000 years: the southwest and central Great Plains will dry out even more than previously thought. Scientific American, February 12, 2015. https://www.scientificamerican.com/article/u-s-droughts-will-be-the-worst-in-1-000-years1/

Kunkel, K. E., L. E. Stevens, S. E. Stevens, L. Sun, E. Janssen, D. Wuebbles, M. C. Kruk, D. P. Thomas, M. Shulski, N. Umphlett, K. Hubbard, K. Robbins, L. Romolo, A. Akyuz, T. Pathak, T. Bergantino, and J. G. Dobson. 2013. Regional climate trends and scenarios for the U.S. National Climate Assessment. Part 4. Climate of the U.S. Great Plains. NOAA Technical Report NESDIS 142-4, 82 pp. https://scenarios.globalchange.gov/report/regional-climate-trends-and-scenarios-us-national-climate-assessment-part-4-climate-us-great

Websites

Great Plains (Third National Climate Assessment, 2014): https://nca2014.globalchange.gov/report/regions/great-plains

montanaclimate.org (online repository for Montana Climate Assessment and other reports): https://montanaclimate.org/

Montana Climate Office (University of Montana): https://climate.umt.edu/

Northwest (Third National Climate Assessment, 2014): https://nca2014.globalchange.gov/report/regions/northwest

Western Regional Climate Center: https://wrcc.dri.edu/

The Climate Explorer: https://crt-climate-explorer.nemac.org/

Earth hazards

General Earth hazards

Books, articles, and reports

2014. Wyoming multi-hazard mitigation plan. Wyoming Office of Homeland Security, Cheyenne, Wyoming. https://drought.unl.edu/archive/plans/GeneralHazard/state/WY_2014.pdf

Epstein, J. B., and D. H. Doctor. 2014. Hydrology, hazards and geomorphic development of gypsum karst in the northern Black Hills, South Dakota and Wyoming. NRC-086, June 20, 2014. PDF: https://www.nrc.gov/docs/ML1417/ML14175B625.pdf

Websites

Be ready Nebraska. https://www.bereadynebraska.com/preparation-101/natural-disasters/

Droughts

Books, articles, and reports

Fischetti, M. 2015. U.S. droughts will be the worst in 1,000 years: the southwest and central Great Plains will dry out even more than previously thought. Scientific American, February 12, 2015. https://www.scientificamerican.com/article/u-s-droughts-will-be-the-worst-in-1-000-years1/

Earthquakes

Books, articles, and reports

2009. Putting down roots in earthquake country: Your handbook for earthquakes in Idaho. Idaho Bureau of Homeland Security, Idaho Geological Survey, and Idaho Citizen Corps. https://adacounty.id.gov/emergencymanagement/wp-content/uploads/sites/39/eqcountry.pdf

Witkind, I. J. The 1959 Hebgen Lake, Montana, earthquake: Two geologic points of view. USGS unnumbered report. https://pubs.usgs.gov/unnumbered/70178963/report.pdf

Yellowstone Volcano Observatory. 2019. 60 years since the 1959 M7.3 Hebgen Lake earthquake: its history and effects on the Yellowstone region. USGS, August 5, 2019. https://www.usgs.gov/news/60-years-1959-m73-hebgen-lake-earthquake-its-history-and-effects-yellowstone-region

Floods

Books, articles, and reports

Hamilton, L. M. 2011. Where the roads end in water: The lake the won't stop rising. The Atlantic, May 13, 2011. https://www.theatlantic.com/national/archive/2011/05/where-the-roads-end-in-water-the-lake-that-wont-stop-rising/238848/

Landslides

Books, articles, and reports

A Brief History of the Gros Ventre Slide Geological Site [Wyoming]. PDF: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5340454.pdf

Websites

Gros Ventre Geological Site [Wyoming] (USDA Forest Service): https://www.fs.usda.gov/recarea/btnf/recarea/?recid=71645

Landslides (Idaho Geological Survey): https://www.idahogeology.org/geologic-hazards/landslides

Landslides (Montana Bureau of Mines and Geology): http://www.mbmg.mtech.edu/MontanaGeology/geohazards/landslides/main.asp

Slope instability and mass wasting at Fargo, North Dakota (J. L. Welsh, B. B. Olson, P. Healey, and D. P. Schwert, North Dakota State University): https://www.ndsu.edu/fargo_geology/mass_wasting/index.htm

Volcanoes

Books, articles, and reports

Dvorsky, G. 2014. A major step to predicting when supervolcanoes will explode. Gizmodo, January 6, 2014. https://gizmodo.com/a-major-step-to-predicting-when-supervolcanoes-will-exp-1495554422

Newitz, A. 2013. What will really happen when the Yellowstone Supervolcano erupts? Gizmodo, May 17, 2013. https://gizmodo.com/what-will-really-happen-when-yellowstone-volcano-has-a-508274690