The Connected Systems of the Columbia River on the Oregon
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The Connected Systems of the Columbia River on the Oregon-Washington Border WASHINGTON The Columbia River, in its 309-mile course along the Oregon-Washington border, provides a rich and varied environment OREGON for the people, wildlife, and plants living and interacting there. The area’s geology is the basis for the landscape and ecosystems we know today. By deepening our understanding of interactions of Earth systems — geosphere, hydrosphere, atmosphere, and biosphere — Earth science helps us manage our greatest challenges and make the most of vital opportunities. ⑮ ⑥ ④ ⑬ ⑧ ⑪ ① ⑦ ② ③ What is a ⑭ ⑫ ⑤ connected system? ⑩ A connected system is a set of interacting components that directly or indirectly influence one another. The Earth system has four major components. The geosphere includes the crust and the interior of the planet. It contains all of the rocky parts of the planet, the processes that cause them to form, and the processes that have caused ⑨ them to change during Earth’s history. The parts can be as small 0 10 20 40 Miles ∆ N as a mineral grain or as large as the ocean floor. Some processes act slowly, like the gradual wearing away of cliffs by a river. Geosphere Others are more dramatic, like the violent release of gases and magma during a volcanic eruption. ① What is a geologic map? The fluid spheres are the liquid and gas parts of the Earth system. The atmosphere includes the mixture of gases that Geologic maps show what kinds of rocks and structures make up a landscape. surrounds the Earth. The hydrosphere includes the planet’s The geologic makeup of an area can strongly influence the kinds of soils, water water system. Its parts include oceans, lakes, rivers, and frozen Hydrosphere resources, flora and fauna, and hazards in an area: the connected systems. water in glaciers. A special property of the fluid spheres is that That’s why it’s important to create and to understand geologic maps. The impact their materials flow. Processes in the fluid spheres include the ⑤ water cycle, the circulation of the atmosphere and oceans, of geology on the connected systems of the Columbia River at a few specific locations and weather. ② is described on this poster. These examples are just a few of the many influences The biosphere contains the living and once-living parts of Atmosphere Biosphere What role does plate tectonics play? of geology in this area. What others can you think of? the Earth system. It is organized into complex webs of micro- organisms, animals, and plants. Processes vary from simple ⑨ ⑪ Geologic Units Geologic Time predator-prey relationships to changes over millions of years Unconsolidated Sediments The generalized rock units and ages shown on this map tell a simplied story of the geologic history of this area by arranging the rock units by type and age. This makes it in the kinds of living things that make up communities. Holocene dune sand possible to organize rocks mapped by dierent geologists across the two states into the The interactions of these systems along the Columbia River ⑥ Quaternary alluvium major kinds of rocks that together have built the Columbia River landscape we see today. Use the time scale below to nd the periods associated with the geologic units—this area can be dramatic and damaging: basalts spill out and build Quaternary mass-wasting deposits developed very recently in the Earth’s history! layers of rock, floods race down the river channel destroying Mount ③ Rainier Quaternary loess Seattle Visit your state’s geologic survey website to nd more geologic maps. everything in their path, volcanoes spew lava, ash and gases, Pleistocene outburst-ood deposits earthquakes and erosion cause landslides. The interactions can Pleistocene alpine glacial drift also be beneficial: plants grow in weathered and deposited soils, Mount Mount St. Helens Adams winds and water produce electrical power, wetlands shelter ⑩ ⑫ Sedimentary Rocks and Deposits GEOLOGIC TIME SCALE er birds and other life, and the river provides transportation and bia Riv Quaternary–Tertiary continental sedimentary rocks and deposits EON ERA PERIOD EPOCH Colum Present Tertiary continental sedimentary rocks Holocene recreational opportunities. Quaternary ⑦ Portland Mount 0.01 Tertiary nearshore sedimentary rocks Pleistocene Hood 2.6 Tertiary marine sedimentary rocks Pliocene 5.3 ④ Miocene Volcanic Rocks and Deposits Neogene 23.0 Cenozoic Oligocene 33.9 Quaternary volcanic rocks Tertiary Eocene Quaternary fragmental volcanic rocks and deposits (includes lahars) 56.0 Earth’s ⑪ Along its length, the Columbia River ecosystem ranges between ⑬ Mount Paleogene Paleocene temperate rainforest and dry grassland. Diverse landforms and Jeerson Quaternary–Tertiary volcanic rocks 66.0 Connected microclimates along the river host many kinds of plants as well as Cretaceous permanent and migratory sh and wildlife, although climate change, Tertiary volcanic rocks, Columbia River Basalt Group 145 ATMOSPHERE Jurassic Systems human activities, and invasive species are endangering native species. 201 The wetlands at Ridgeeld National Wildlife Refuge provide habitat Tertiary volcanic rocks ⑧ Mesozoic Triassic for animals and waterfowl like this great blue heron. Tertiary fragmental volcanic rocks Phanerozoic 252 ⑫ Tribal peoples, attracted by salmon and trade, historically ⑮ ⑮ Plate tectonics is a theory that explains many of the Permian BIOSPHERE ⑤ The Columbia River’s heavy ow makes it ideal for generating large-scale geologic processes we see around us. In the Pacic 299 migrated along the Columbia River. Left behind on the basalt are Intrusive Rocks Pennsylvanian electricity. Collectively, 14 hydroelectric dams on the Columbia River in about 90 art sites containing paintings and carvings, called Northwest, as new magma wells up between the Pacic plate 323 Oregon, Washington, and British Columbia are the foundation of the and the Juan de Fuca plate, the Juan de Fuca plate slides Mississippian pictographs and petroglyphs. About half these ancient stones Quaternary intrusive rocks Carboniferous HYDROSPHERE Pacic Northwest’s power supply. Dams also provide ood control and were rescued before damming of the river covered them with water, (subducts) under the North American plate. Stresses that 359 irrigation, and aid in shipping navigation. The Dalles Dam is almost build up from the movement are relieved by earthquakes Quaternary–Tertiary intrusive rocks Devonian and they were carefully brought to the Columbia Hills State Park, 419 9,000 feet long, and with 22 turbines, it is one of the top ten north of The Dalles. all along the Cascadia subduction zone. As the subducting ⑭ Tertiary intrusive rocks Paleozoic Silurian hydropower dams in the United States. Because dams block salmon plate plunges deeper, the hot, more buoyant, and viscous 443 migrations, sh ladders have been installed in many of the lower ⑬ The lava ows surrounding the Columbia River Gorge produce, magma travels up to create the line of snow-topped Ordovician Columbia River dams. dark, ne, and highly fertile soil, and much of the land in this area is stratovolcanoes that make up the Cascade Range. Other Features 485 AGE IN MILLIONS OF YEARS BEFORE PRESENT BEFORE OF YEARS IN MILLIONS AGE dedicated to farming. Because the areas east of the Cascade The Columbia River Gorge cuts through this range. Cambrian ⑥ Oregon and Washington are connected by 16 bridges that allow ⑩ Some of the highest wind speeds in Washington and Oregon Glacier and ice elds 541 Mountains, like Kennewick, Washington, are dry, farmers plant crops To the east of the Cascades, crustal extension and shipping and travel across the Columbia River. The Astoria-Megler are in and near the Columbia River Gorge. Created by dierences in in circles and use a center-pivot system for irrigation. movement of a mantle plume beneath the Yellowstone Water Proterozoic Bridge, at 4.1 miles long, is the longest truss bridge in North America, atmospheric pressure east and west of the Cascades, the wind is ⑭ From March to October, Chinook, Coho, Sockeye, and Steelhead hot spot cause more earthquakes and volcanic activity. 2500 with annual daily trac of 23,300 vehicles. Large earthquakes harnessed to produce electricity using wind turbines. Both Oregon Fault salmon return to the Columbia River and its tributaries to spawn Through all these mechanisms, plate tectonics can cause bridge collapse and block waterway access to industry and Washington have wind turbine farms near the Gorge, and both Archean where they hatched. To migrate upstream, these and many thousands continues to shape the landscape. and population centers. rate among the top ten states with wind turbine installations. 4000 of other sh must pass through manmade locks and dams. The wind also provides excellent windsurng. GEOSPHERE ⑦ Since the damming of the Columbia River, deltas (fan-shaped Hadean Precambrian deposits of sediment) began reforming at the mouths of its tributaries. 4567 The Hood River Delta grew signicantly after a debris ow−a rapidly moving destructive landslide−during a winter storm in 2007. Time scale modied from International Commission on Stratigraphy Examples of the role of geology ③ Many of the slopes along the north bank of the Columbia River This delta also receives large pulses of sediment due to outburst Gorge contain large landslides, including the Bonneville landslide, in Earth’s connected systems ooding from receding glaciers on Mount Hood. along the Columbia River located a few miles west of Stevenson, Washington. According to native legend