Detailed descriptions of Ice Age Flood- and Glacial-scapes for computer, mobile device, or printing
Ancient Cataclysmic Floods - Ancient Cataclysmic Floods were Pleistocene Ice Age Floods that occurred as early as 1.5 million years ago and that preceded the better known Missoula Floods 18,000-13,000 years ago in the Pacific Northwest.
Beacon Rock - Beacon Rock is one of the most prominent and distinctive geological features in the scenic Columbia River Gorge.
Bonneville Landslide(s) - About 50 mi2 of the area around Stevenson, WA, is mantled by 215 discrete landslides of various ages, ranging from more than 15,000 years old to currently active.
Camas Prairie Giant Current Ripples - It is now generally agreed that the Camas Prairie giant ripple marks were formed by deep, raging Ice Age floodwaters flowing swiftly from Glacial Lake Missoula through this area of a failed ice dam at speeds of 50 miles per hour or more.
Chandler Butte Landslide - The Chandler Butte landslide complex is a huge area of land along the north slope of the tall and steep Horse Heaven Hills between Benton City and Prosser.
Chronology of Missoula Flood Deposits at the Coyote Canyon Mammoth Site, Washington State, USA - George V. Last and Tammy M. Rittenour, 2021. Late Pleistocene outburst megafloods, mostly from glacial Lake Missoula, hydraulically ponded behind downstream constrictions in the Columbia River in southeastern Washington State, USA. The lack of flood deposits in the Coyote Canyon area younger than 16 ka supports the current understanding that multiple late Pleistocene megafloods occurred between 20 ka and 14 ka and that earlier floods produced higher flood stages than later ones.
Drumheller Channels - During many of the Ice Age Floods, the Okanogan lobe of ice blocked the Columbia River near Grand Coulee Dam. Between floods, the ice lobe forced drainage from the Columbia River and Glacial Lake Columbia to go down Grand Coulee through Moses Lake, Drumheller Channels, and Lower Crab Creek Coulee before emptying into the present Columbia Valley just north of Sentinel Gap.
Dry Falls - As the name suggests, Dry Falls no longer carries water, but is the remnant of what was once the largest waterfall known to have existed on earth.
Eddy Narrows - The flume shaped section of this canyon is the throttle that controlled the flow rates of the giant Ice Age Floods after the ice dam holding back Glacial Lake Missoula failed catastrophically.
Erratics and Bergmounds - Icebergs that floated on the Ice Age floods into the Pasco Basin and elsewhere and became stuck there, often left behind ice-rafted debris including isolated and clusters of boulders composed of rock types totally foreign to the area, called erratics and bergmounds.
Farragut State Park - Farragut State Park is located at the “breakout” of Glacial Lake Missoula floods where the ice dam in the Clark Fork valley and the 20-mile-long tongue of ice occupying the Lake Pend Oreille basin failed and a torrent of water and ice burst from the south end of the lake.
Glacial Lake Missoula Rhythmites - This is the type section for Lake Missoula rythmite clays and silts. These sediments are finely laminated, resembling varves that, on close inspection, appear as “…individual units ...with no connotation of time, whereas varves are couplets that may represent annual deposits.” (Chambers, 1984)
Glacial Lake Missoula Strandlines - The slopes on the northwestern facing aspects of the hills around Missoula, MT, have well developed strandlines or shorelines left over from Glacial Lake Missoula about 20,000 years ago.
Gorge Discovery Center Kolk Pond - Just outside the giant windows at the end of the Columbia Gorge Discovery Center main gallery lies a large, water-filled Kolk pond dug into the basalt bedrock by turbulent flood waters during one or more of the Ice Age Floods.
Green Monarch Ridge Ice Dam - Green Monarch Ridge lies along the former edge of the Purcell Trench Ice Lobe where it divided into four sublobes, one of which was responsible for damming the mouth of the Clark Fork drainage basin and forming Lake Missoula, the source of the waters for the Ice Age Floods.
HOODOO CHANNEL AND VALLEY: Remnants of the Ice Age Floods - When travelling north on Idaho State Hwy 95 out of Coeur d’Alene, you will be travelling on Ice Age Flood deposits that constitute the Rathdrum/Spokane Aquifer, the primary source of water for over 500K people living between Spokane, WA and Careywood, ID.
Hoodoo Scablands at John Day Dam - Hoodoo Scablands just upstream of the John Day Dam are characterized by rubbly low-relief mounds and unusual standing spires (hoodoos) of remnant, Floods battered basalt.
Horsethief Butte and Scablands - Composed of hexagonal columns of Wanapum basalt flows about 15 million years old, Horsethief Butte was scoured and streamlined to a teardrop shape while being cleansed of most of its soil and rock cover by 40 to 120 Bretz Floods at the end of the last Ice Age, 12,000 to 18,000 years ago.
Ice Age Floods Final Rest - The sediment-laden Ice Age Floods swept down the then exposed Columbia River channel, now the Astoria and Willapa Submarine Canyons, and on across the deep water Astoria Fan, Escanaba Trough and Tufts Fan.
Lake Lewis Isles is the name given to several hills south of the Tri-Cities whose crests rose above maximum flood level (~1,250 feet elev.) during Ice Age flooding, making them islands in temporary Lake Lewis.
Monster Rock, Ephrata Fan - The basalt and granite boulders now littering the Ephrata Fan were carried there by torrents of water that gushed out of a canyon called the Grand Coulee. The largest of these, “Monster Rock”, is estimated to be about 8m (25 feet) in diameter and contains over 500 cubic yards of rock that weighs over 1,500 tons!
Mosier Granodiorite Erratic - In the bowels of an immense State of Oregon gravel pit, the eye is immediately caught by the huge lone boulder of white granodiorite in a sea of much smaller-sized chunks of black basalt.
Palouse Falls and Trails - Iconic Palouse Falls drops 200 feet from a narrow cataract to an incredibly picturesque bowl of churning water surrounded by immense palisades of Columbia River Basalt. It lies on the Palouse River about 4 mi (6 km) upstream of the confluence with the Snake River in southeast Washington.
Portland Basin, Willamette Valley, Bellevue Erratic - The Portland region owes its rich agriculture and beautiful geography to a series of massive Ice Age Floods that burst from an ice dam about 15,000 years ago.
Puget Glacial Retreat Remnants - At the end of the last ice age glacial stage, the stagnating, melting and retreating Puget Lobe left behind moraines, erratics and other sediment deposits, pro-glacial lake beds and terraces, fields of mima mounds, and various meltwater channels and spillways throughout the Puget Sound area.
Puget Ice Marginal Meltwater Channels - Ice-marginal meltwater channels formed along the margins of the Puget ice lobe by meltwater and runoff of western Cascade rivers. Jökulhlaups (glacial outburst floods) occurred along these channels when impounded waters (temporary lakes) from Cascade rivers periodically broke through ice or moraine dams at the margin of the Puget lobe.
Puget Ice Plucking and Bedrock Scouring - During the most recent glacial cycle of the Ice Age, some 19,000 years ago, a massive ice sheet crept from southwestern Canada into the Puget Sound region. Glacial ice 1000's of feet thick gouged, grooved, scoured and plucked at bedrock, leaving indelible marks on bedrock outcrops throughout the Puget Sound area.
Puget Major Troughs and Drumlins - Channels of subglacial meltwater exiting a glacier can create deep troughs and remnant drumlin ridges by erosion of soft-sediment or hard-rock by the turbulent meltwater.
Puget Meltwater Escape to the Southwest - During Ice-Age times, meltwater that pooled ahead of the advancing lobe in proglacial lakes drained southward in raging torrents forming large river valleys until the outlet to the Strait of Juan de Fuca reopened near the end of the Vashon glacial retreat. Some estimates equate seasonal Ice-Age Chehalis River flow rates of meltwater, precipitation, and periodic jøkulhlaups from the eastern ice margin with present-day Columbia River flow rates.
Rowena Crest - Overlooking a major chokepoint along the Ice Age Floods path, Rowena Crest lies at nearly 700 feet above the Columbia River at the upstream end of Rowena Plateau, a miles-long promontory that protrudes into the path of the river.
Smith Canyon Coulee - Lower Smith Canyon Coulee is a dry, shallow coulee that carried floodwaters coming off the Channeled Scabland into the Snake River valley northeast of the Tri-Cities.
Streamlined Palouse Hills Video - This 11-minute video is the 19th in a series of online YouTube videos that focus on the many unique and spectacular features created by Ice Age Megafloods. Streamlined Palouse Hills is the latest installment to the Ice Age Floodscapes YouTube Channel. In 1923, J Harlen Bretz wrote about Streamlined Palouse Hills: "It seems clear that they are but remnants of a once continuous cover of the basalt, and that the scablands have resulted from removal of the Palouse Hills by erosion by some unusual way. The basalt of the scablands is the firm and resistant foundation on which the hills stand."
Temporary Lake Condon - Lake Condon was a so-called temporary lake in the Pacific Northwest region, formed periodically by repeated backup and ponding of Ice Age Missoula Floods and the pluvial Lake Bonneville Flood during the latest Ice Age period from 18,000 to 13,000 years ago.
Wallula Gap and Trails - Two-Sisters Trail ascends to the base of a pair of basalt pillars, created by extreme erosion of fractured and weakened basalt by the powerful Ice Age floods. Great views are available both up and down the Columbia River from the saddle between the two pillars.
White Bluffs - A small section of the White Bluffs are rhythmite deposits, 17,550-12,500 years old, that fill an erosional gap in the underlying Ringold Formation. They were laid down as each of 40 or more Ice Age Floods backed up behind the narrow constriction at Wallula Gap, submerging the entire White Bluffs area under temporary Lake Lewis.
Williams Lake Cataract - Williams Lake Cataract is an ancient, dry waterfall at the head of a recessional canyon near Spokane in eastern Washington that was left behind by the Ice Age Floods ripping out basalt bedrock to produce this massive cataract in the Cheney-Palouse Scabland Tract.
Yakima Bluffs - Evidence for at least two very old Ice Age floods is exposed in bluffs along the banks of the Yakima River. Flood gravels with normal magnetic polarity and covered with a thick layer of soil-forming caliche indicate one of the floods occurred >200,000 years ago.
Yakima River Badlands - The Badlands is a spectacular erosional flood feature located along the Yakima River between Benton City and Prosser. The Badlands formed along a constriction in the Yakima Valley.
