Nepedia
Back to Discover
Advanced Reader
🗺️

Great Basin

geography Maturity 5-7 Next article →

The Great Basin is a vast geographic region in North America.

Great Basin definition map
Great Basin definition map

It is most commonly defined as a large hydrographic area. This means it is a collection of endorheic watersheds. An endorheic watershed is a system where water has no outlet to the ocean. Instead of flowing to the sea, water stays within the land. It might evaporate, sink into the ground, or collect in salty lakes. This unique hydrological setup makes the Great Basin a distinct part of the continent.

This region covers a massive amount of land. It spans nearly all of Nevada and much of Utah. It also includes parts of California, Idaho, Oregon, Wyoming, and Baja California in Mexico. The area is bounded by several major landmarks. To the east lie the Wasatch Mountains. To the west are the Sierra Nevada and Cascade Ranges. To the north sits the Snake River Basin. The southern boundary is less clearly defined by specific landmarks.

The landscape is defined by basin and range topography.

Basin range province
Basin range province

This shape is caused by geological forces stretching the Earth's crust. This process is called lithospheric extension. As the crust thins and stretches, it creates many north-south trending mountain ranges. These ranges are separated by flat valleys or basins. Geologists describe this using the terms horst and graben. A horst is an upthrown block of crust. A graben is a down-dropped block of crust. These features create the many mountains seen in Nevada today.

Over thousands of years, sediment has filled these basins. This has created flat lacustrine plains from ancient lake beds. For example, Lake Bonneville formed about 32,000 years ago. It eventually overflowed during the Bonneville Flood about 14,500 years ago. This event lowered the water to the level of the modern Great Salt Lake. Other large Pleistocene lakes included Lake Lahontan and Lake Mojave. Today, the region contains many smaller 'drains' like Pyramid Lake and the Humboldt Sink.

The ecology of the Great Basin is shaped by elevation and climate.

Great Basin Ecoregions
Great Basin Ecoregions

As elevation increases, temperatures decrease and precipitation increases. This creates several different ecoregions. The region overlaps four deserts. The hot Mojave and Colorado Deserts are to the south. The cold Great Basin and Oregon High Deserts are to the north. You can tell them apart by their plants. Joshua trees and creosote bushes grow in the hot deserts. However, they do not grow in the cold deserts.

High in the mountains, different life forms thrive. You might find pinyon-juniper woodlands on the slopes. Higher still, there are stands of limber pine and Great Basin bristlecone pine. In areas with steady water, cottonwoods and quaking aspen grow in groves. Many species are endemic, meaning they are found nowhere else. This is because the mountain ranges are isolated from one another. Wildlife includes pronghorn, mule deer, and mountain lions. You may also see golden eagles or various lizards.

Human history in the Great Basin goes back a very long time.

North American cultural areas
North American cultural areas

Indigenous populations have lived here since at least 10,000 B.C. Paleo-Indians were early hunters in the region. They hunted animals like bison and the extinct mammoth. Because they followed migrating animals, they did not have permanent villages. Later, groups like the Great Basin Desert Archaic inhabited the area. Today, the region has modern cities like Reno and the Wasatch Front. Some roads, like US 50, are even known as "The Loneliest Road in America."

US west coast physiographic regions map
US west coast physiographic regions map

The Great Basin is a complex system of geology and biology. It shows how a closed water system functions. It also demonstrates how tectonic forces can reshape a continent. The variety of life, from desert lizards to alpine pines, shows the impact of elevation. Whether looking at the high summit of Mount Whitney or the low Badwater Basin, the Great Basin is a land of extremes.

635 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (7)
File:Great Basin definition map.gif
Great Basin definition map.gif
File:Great Basin Ecoregions.gif
Great Basin Ecoregions.gif
File:WheelerSnow.JPG
WheelerSnow.JPG
File:Basin range province.jpg
Basin range province.jpg
File:US west coast physiographic regions map.jpg
US west coast physiographic regions map.jpg
File:North American cultural areas.png
North American cultural areas.png
File:Rain in the Wah Wah Valley.jpg
Rain in the Wah Wah Valley.jpg
More to explore

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.