The Withrow Moraine and Jameson Lake Drumlin Field is a

National Park Service The National Park Service (NPS) is an agency of the United States federal government within the U.S. Department of the Interior that manages all national parks, most national monuments, and other natural, historical, and recreational propert ...

–designated privately owned

National Natural Landmark The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best ...

located in Douglas County,

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

state,

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. Withrow Moraine is the only

Ice Age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...

terminal moraine A terminal moraine, also called end moraine, is a type of moraine that forms at the terminal (edge) of a glacier, marking its maximum advance. At this point, debris that has accumulated by plucking and abrasion, has been pushed by the front edge ...

on the Waterville Plateau section of the Columbia Plateau. The

drumlin A drumlin, from the Irish word ''droimnín'' ("littlest ridge"), first recorded in 1833, in the classical sense is an elongated hill in the shape of an inverted spoon or half-buried egg formed by glacial ice acting on underlying unconsolidated ...

field includes excellent examples of glacially-formed elongated

hill A hill is a landform that extends above the surrounding terrain. It often has a distinct summit. Terminology The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally considered to be not a ...

Geologic history

The plateau

The Withrow Moraine and Jameson Lake Drumlin Field National Natural Landmark is located on the Waterville Plateau, which lies in the northwest corner of the

Columbia River Plateau The Columbia Plateau is a geologic and geographic region that lies across parts of the U.S. states of Washington, Oregon, and Idaho. It is a wide flood basalt plateau between the Cascade Range and the Rocky Mountains, cut through by the Columbi ...

. The plateau is formed on top of the

Columbia River Basalt Group The Columbia River Basalt Group is the youngest, smallest and one of the best-preserved continental flood basalt province on Earth, covering over mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada. The basalt grou ...

large igneous province A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation ...

that lies across parts of the states of

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...

, and

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyomi ...

in the

United States of America The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...

. During the middle to late

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

, one of the largest

flood basalt A flood basalt (or plateau basalt) is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava. Many flood basalts have been attributed to the onset of a hotspot reac ...

s ever to appear on the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

's surface engulfed about 163,700 km² (63,000 mile²) of the Pacific Northwest, forming a large igneous province with an estimated volume of 174,300 km³. Eruptions were most vigorous from 17 to 14 million years ago, when over 99% of the basalt was released. Less extensive eruptions continued from 14 to 6 million years ago. These lava flows have been extensively exposed by the erosion resulting from the

Missoula Floods The Missoula floods (also known as the Spokane floods or the Bretz floods or Bretz's floods) were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the las ...

, which laid bare many layers of the basalt flows on the edges of the plateau at

Grand Coulee 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 ...

and

Moses Coulee Moses Coulee is a canyon in the Waterville plateau region of Douglas County, Washington. Moses Coulee is the second-largest and westernmost canyon of the Channeled Scablands, located about to the west of the larger Grand Coulee. This water channe ...

.''Portions of this article, including a figure, are adapted from works of the United States Government, which are in the

public domain The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired, ...

The glacial history

Two million years ago the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

epoch began and

Ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...

glaciers invaded the area. They scoured the Columbia River Plateau, reaching as far south as the middle of the Waterville Plateau highlands above the Grand Coulee and south to the head of

. In some areas north of the

they were as much as 3 km (10000 feet) thick. Grooves in the exposed granite bedrock are still visible in the area from the movement of glaciers and numerous

glacial erratic 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 ' ("to wander"), are carried by glacial ice, often over distances of hundre ...

s in the elevated to the Northwest of the coulee.

Progress of the Okanogan Lobe of the Cordilleran Glacier

The Okanogan lobe of the Cordilleran Ice Sheet moved down the

Okanogan River The Okanogan River (known as the Okanagan River in Canada) is a tributary of the Columbia River, approximately 115 mi (185 km) long, in southern British Columbia and north central Washington. It drains a scenic plateau region called th ...

valley, covering 500 mi² of the Waterville Plateau and blocked the ancient route of the Columbia River, backing up water to create

Glacial Lake Columbia Glacial Lake Columbia was the lake formed on the ice-dammed Columbia River behind the Okanogan lobe of the Cordilleran Ice Sheet when the lobe covered of the Waterville Plateau west of Grand Coulee in central Washington state during the Wis ...

. Initially water discharged from Lake Columbia by running up through the head of Grand Coulee and down through Foster Coulee to rejoin the Columbia River. As the glacier moved further south, Foster Coulee was cut off and the Columbia River then discharged through

, which runs southward slightly to the east of the ancient and current course of the Columbia. As the Okanogan lobe grew, it blocked Moses Coulee as well; the Columbia found the next lowest route through the region which was eroded to become the modern

After the glacier

As the Okanogan lobe melted, the northern half of the Waterville Plateau, including the upper portions of Moses Coulee, were littered with clear evidence of its passing. The glacier left behind a blanket of glacial till, up to 50 feet thick in places. This glacial till, composed of clay, silt, sand, gravel, cobblestones, and erratic boulders, covers most of the upper Moses Coulee. The melting glacier discharged both down Moses Coulee and into the Grand Coulee as is evident in the

Sims Corner eskers and kames Sims Corner Eskers and Kames National Natural Landmark of Douglas County, Washington and nearby McNeil Canyon Haystack Rocks and Boulder Park natural landmarks contain excellent examples of Pleistocene glacial landforms. Sims Corner Eskers and Kam ...

.Washington history link.
/ref>

References

External links

U.S. National Park Service material on Withrow Moraine and Jameson Lake Drumlin Field

Photo gallery

Image:Mixed-Eratics-PB110053.JPG, Mixed erratics located near Sims Corner. The nearest is

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...

, which the ones behind it are

granite Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies under ...

. Image:Glacial-Drift-PB110031.JPG, A kame among the glacial drift on the terminal moraine. Image:Erratics-PB110026.JPG, Terminal moraine of the Okanagon Lobe Image:Erratics-Cascades-PB110028.JPG, Multiple erratics on the terminal moraine of the Okanogan Lobe. Cascade mountains in the background. Image:Terminal-Morraine-PB110030.JPG, Multiple erratics on the terminal moraine of the Okanogan Lobe. {{DEFAULTSORT:Withrow Moraine And Jameson Lake Drumlin Field Protected areas of Douglas County, Washington Glaciology of the United States Moraines of the United States Landforms of Douglas County, Washington National Natural Landmarks in Washington (state)