The Willamette River is a major tributary of the Columbia River, accounting for 12 to 15 percent of the Columbia's flow. The Willamette's main stem is 187 miles (301 km) long, lying entirely in northwestern Oregon in the United States. Flowing northward between the Oregon Coast Range and the Cascade Range, the river and its tributaries form the Willamette Valley, a basin that contains two-thirds of Oregon's population, including the state capital, Salem, and the state's largest city, Portland, which surrounds the Willamette's mouth at the Columbia.
The Missoula floods were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. These floods were the result of periodic sudden ruptures of the ice dam on the Clark Fork River that created Glacial Lake Missoula. After each ice dam rupture, the waters of the lake would rush down the Clark Fork and the Columbia River, flooding much of eastern Washington and the Willamette Valley in western Oregon. After the lake drained, the ice would reform, creating Glacial Lake Missoula again.
Lake Missoula was a prehistoric proglacial lake in western Montana that existed periodically at the end of the last ice age between 15,000 and 13,000 years ago. The lake measured about 7,770 square kilometres (3,000 sq mi) and contained about 2,100 cubic kilometres (500 cu mi) of water, half the volume of Lake Michigan.
Grand Coulee is an ancient river bed in the U.S. state of Washington. This National Natural Landmark stretches for about 60 miles (100 km) southwest from Grand Coulee Dam to Soap Lake, being bisected by Dry Falls into the Upper and Lower Grand Coulee.
A glacial erratic is glacially deposited rock differing from the type of rock native to the area in which it rests. Erratics, which take their name from the Latin word errare, are carried by glacial ice, often over distances of hundreds of kilometres. Erratics can range in size from pebbles to large boulders such as Big Rock in Alberta.
The Channeled Scablands are a relatively barren and soil-free region of interconnected relict and dry flood channels, coulees and cataracts eroded into Palouse loess and the typically flat-lying basalt flows that remain after cataclysmic floods within the southeastern part of the U.S. state of Washington. The Channeled Scablands were scoured by more than 40 cataclysmic floods during the Last Glacial Maximum and innumerable older cataclysmic floods over the last two million years. These floods were periodically unleashed whenever a large glacial lake broke through its ice dam and swept across eastern Washington and down the Columbia River Plateau during the Pleistocene epoch. The last of the cataclysmic floods occurred between 18,200 and 14,000 years ago.
The Willamette Meteorite, officially named Willamette and originally known as Tomanowos by the Clackamas Chinook Native American tribe, is an iron-nickel meteorite found in the U.S. state of Oregon. It is the largest meteorite found in the United States and the sixth largest in the world. There was no impact crater at the discovery site; researchers believe the meteorite landed in what is now Canada or Montana, and was transported as a glacial erratic to the Willamette Valley during the Missoula Floods at the end of the last Ice Age. It has long been held sacred by indigenous peoples of the Willamette Valley, including the federally recognized Confederated Tribes of the Grand Ronde Community of Oregon (CTGRC).
Dry Falls is a 3.5-mile-long (5.6 km) scalloped precipice with four major alcoves, in central Washington scablands. This cataract complex is on the opposite side of the Upper Grand Coulee from the Columbia River, and at the head of the Lower Grand Coulee, northern end of Lenore Canyon. According to the current geological model, catastrophic flooding channeled water at 65 miles per hour through the Upper Grand Coulee and over this 400-foot (120 m) rock face at the end of the last glaciation. It is estimated that the falls were five times the width of Niagara Falls, with ten times the flow of all the current rivers in the world combined.
Sullivan's Gulch is a neighborhood in the Northeast section of Portland, Oregon. The name commemorates Timothy Sullivan, an early farmer in the area. Sullivan settled his donation land claim on January 27, 1851. He was born in Ireland in 1805, received citizenship in the United States in 1855, and most likely received title to the claim around 1863.
The Touchet Formation or Touchet beds consist of large quantities of gravel and fine sediment which overlay almost a thousand meters of volcanic basalt of the Columbia River Basalt Group in south-central Washington and north-central Oregon. The beds consist of between 6 and 40 distinct rhythmites – horizontal layers of sediment, each clearly demarcated from the layer below. These Touchet beds are often covered by windblown loess soils which were deposited later; the number of layers varies with location. The beds vary in depth from 330 ft (100 m) at lower elevations where a number of layers can be found to a few extremely thin layers at the maximum elevation where they are observed.
Lake Lewis was a temporary lake in the Pacific Northwest region of North America, largely formed by the Missoula Floods in about the 14th millennium B.C.
The Withrow Moraine and Jameson Lake Drumlin Field is a National Park Service–designated privately owned National Natural Landmark located in Douglas County, Washington state, United States. Withrow Moraine is the only Ice Age terminal moraine on the Waterville Plateau section of the Columbia Plateau. The drumlin field includes excellent examples of glacially-formed elongated hills.
The Alameda Ridge is a large gravel bar located in Portland, Oregon, United States. It forms a ridgeline above much of north and southeast Portland, with views of downtown and west side neighborhoods. Alameda Ridge runs through the Madison South, Roseway, Rose City Park, Beaumont-Wilshire, Alameda, and Sabin neighborhoods.
Erratic Rock State Natural Site is a state park in the Willamette Valley of Oregon, United States. Featuring a 40-short-ton (36 t) glacial erratic from the Missoula Floods, the small park sits atop a foothill of the Northern Oregon Coast Range in Yamhill County between Sheridan and McMinnville off Oregon Route 18. The day use only park is owned and maintained by the Oregon Parks and Recreation Department.
The Willamette Valley ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency in the U.S. states of Oregon and Washington. Slightly larger than the Willamette Valley for which it is named, the ecoregion contains fluvial terraces and floodplains of the Willamette River system, scattered hills, buttes, and adjacent foothills. It is distinguished from the neighboring Coast Range, Cascades, and Klamath Mountains ecoregions by lower precipitation, lower elevation, less relief, and a different mosaic of vegetation. Mean annual rainfall is 37 to 60 inches, and summers are generally dry. Historically, the region was covered by rolling prairies, oak savanna, coniferous forests, extensive wetlands, and deciduous riparian forests. Today, it contains the bulk of Oregon's population, industry, commerce, and agriculture. Productive soils and a temperate climate make it one of the most important agricultural areas in Oregon.
The Ice Age Floods National Geologic Trail is a network of routes connecting natural sites and facilities that provide interpretation of the geological consequences of the Glacial Lake Missoula floods of the last glacial period that occurred about 18,000 to 15,000 years ago. It includes sites in Washington, Oregon, Idaho, and Montana. It was designated as the first National Geologic Trail in the United States in 2009.
Lake Condon was a temporary lake in the Pacific Northwest region of North America, formed periodically by the Missoula Floods from 15,000 to 13,000 BC.
The Willamette Valley is a 150-mile (240 km) long valley in Oregon, in the Pacific Northwest region of the United States. The Willamette River flows the entire length of the valley and is surrounded by mountains on three sides: the Cascade Range to the east, the Oregon Coast Range to the west, and the Calapooya Mountains to the south.
Badger Mountain is a small mountain in Richland, Washington. Badger rises above the Tri-Cities connected to the smaller Candy Mountain via Goose Gap, is visible throughout much of the area and is a popular hiking destination for a wide variety of climbers. There are a number of trails climbing the mountain with varying levels of difficulty. Most of Badger Mountain is protected by the Badger Mountain Centennial Preserve, but the radio towers at the peak are private property. There are two summits on Badger Mountain, named the East Summit and the West Summit. The West Summit is the highest.
Jump off Joe is a butte in the Horse Heaven Hills south of Kennewick in the U.S. state of Washington. Jump off Joe rises above the Tri-Cities and is visible throughout much of the region, including in parts of Umatilla and Morrow Counties in Oregon to the south. A gravel road approaches the summit from the south up a steep incline. On a clear day, visitors to the summit can see Mount Hood, Mount Adams and Mount Rainier.
