Megaflood Adventure Section 3
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CATASTROPHIC FLOOD FEATURES at CAMAS PRAIRIE, MONTANA More Unusual Currents in Glacial Lake Missoula
CATASTROPHIC FLOOD FEATURES AT CAMAS PRAIRIE, MONTANA More Unusual Currents in Glacial Lake Missoula 2 CATASTROPHIC FLOOD FEATURES AT CAMAS PRAIRIE, MONTANA More Unusual Currents in Glacial Lake Missoula KEENAN LEE DEPARTMENT OF GEOLOGY AND GEOLOGICAL ENGINEERING COLORADO SCHOOL OF MINES GOLDEN COLORADO 80401 2009 3 CONTENTS Page ABSTRACT 4 INTRODUCTION 5 LOCATION AND SETTING 5 THE CAMAS PRAIRIE BASIN 6 INFLOW SUBLAKE NOTCHES AND RELATED FEATURES 8 Wills Creek Pass Sublake Notch System 11 Markle Pass Sublake Notch System 13 Big Creek Pass Sublake Notch System 14 Duck Pond Pass Sublake Notch System 16 CAMAS PRAIRIE FLOOD OUTLETS 16 Rainbow Lake Outlet System 16 Perma Outlet System 21 GIANT CURRENT RIPPLES 23 Giant Current Ripple Fields 24 Characteristics of Giant Current Ripples 25 Analysis of Giant Current Ripple Data 28 Comparison of GCRs at Camas Prairie with Other Ripple Studies 29 Analysis of GCR Data to Estimate Paleohydraulic Parameters 30 SUMMARY 31 ACKNOWLEDGEMENTS 33 REFERENCES 33 TABLES 34 4 ABSTRACT Camas Prairie preserves landforms and bedforms that document catastrophic currents at the bottom of glacial Lake Missoula when its glacier dam broke. Although similar features occur in the scablands of eastern Washington, the currents there were channeled floods that flowed downhill; here the sublake currents often flowed uphill. Similar catastrophic lake-bottom currents have been documented elsewhere only in the Altai flood of Siberia. When the ice dam failed and flooding began, the northern rim of the Camas Prairie Basin and part of the eastern rim were under water, forming sublake divides, or ridges. All flow into the basin came over the basin rims, and all of the lake-bottom currents were flowing uphill to enter the basin. -
The Missoula Flood
THE MISSOULA FLOOD Dry Falls in Grand Coulee, Washington, was the largest waterfall in the world during the Missoula Flood. Height of falls is 385 ft [117 m]. Flood waters were actually about 260 ft deep [80 m] above the top of the falls, so a more appropriate name might be Dry Cataract. KEENAN LEE DEPARTMENT OF GEOLOGY AND GEOLOGICAL ENGINEERING COLORADO SCHOOL OF MINES GOLDEN COLORADO 80401 2009 The Missoula Flood 2 CONTENTS Page OVERVIEW 2 THE GLACIAL DAM 3 LAKE MISSOULA 5 THE DAM FAILURE 6 THE MISSOULA FLOOD ABOVE THE ICE DAM 6 Catastrophic Flood Features in Eddy Narrows 6 Catastrophic Flood Features in Perma Narrows 7 Catastrophic Flood Features at Camas Prairie 9 THE MISSOULA FLOOD BELOW THE ICE DAM 13 Rathdrum Prairie and Spokane 13 Cheny – Palouse Scablands 14 Grand Coulee 15 Wallula Gap and Columbia River Gorge 15 Portland to the Pacific Ocean 16 MULTIPLE MISSOULA FLOODS 17 AGE OF MISSOULA FLOODS 18 SOME REFERENCES 19 OVERVIEW About 15 000 years ago in latest Pleistocene time, glaciers from the Cordilleran ice sheet in Canada advanced southward and dammed two rivers, the Columbia River and one of its major tributaries, the Clark Fork River [Fig. 1]. One lobe of the ice sheet dammed the Columbia River, creating Lake Columbia and diverting the Columbia River into the Grand Coulee. Another lobe of the ice sheet advanced southward down the Purcell Trench to the present Lake Pend Oreille in Idaho and dammed the Clark Fork River. This created an enormous Lake Missoula, with a volume of water greater than that of Lake Erie and Lake Ontario combined [530 mi3 or 2200 km3]. -
The Lake Missoula Floods and the Channeled Scabland Author(S): J
The Lake Missoula Floods and the Channeled Scabland Author(s): J. Harlen Bretz Source: The Journal of Geology, Vol. 77, No. 5 (Sep., 1969), pp. 505-543 Published by: The University of Chicago Press Stable URL: http://www.jstor.org/stable/30062250 . Accessed: 15/01/2015 10:22 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The University of Chicago Press is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Geology. http://www.jstor.org This content downloaded from 128.193.164.203 on Thu, 15 Jan 2015 10:22:29 AM All use subject to JSTOR Terms and Conditions THE LAKE MISSOULA FLOODS AND THE CHANNELED SCABLAND1 J HARLEN BRETZ Department of the Geophysical Sciences, University of Chicago ABSTRACT This paper reviews the outstanding evidence for (1) repeated catastrophic outbursts of Montana's glacially dammed Lake Missoula, (2) consequent overwhelming in many places of the preglacial divide along the northern margin of the Columbia Plateau in Washington, (3) remaking of the plateau's preglacial drainage pattern into an anastomosing complex of floodwater channels (Channeled Scabland) locally eroded hundreds of feet into underlying basalt, (4) convergence of these flood-born rivers into the Columbia Valley at least as far as Portland, Oregon, and (5) deposition of a huge delta at Portland. -
The Stonecutter and the Missoula
WashingtonHistory.org THE STONECUTTER & THE MISSOULA FLOOD ERRATICS By Nathan Reynolds COLUMBIA The Magazine of Northwest History, Spring 2006: Vol. 20, No. 1 In 1884 a local stonecutter installed a granite cornerstone in the new Catholic church under construction in Vancouver, Washington. The origin of this block of stone has presented something of a mystery. Was it mined from the only vein of granite in the area, which lay at some distance and several thousand feet in elevation, or was it somehow obtained from a source much closer at hand? An examination of competing geological theories and information provided by local residents helps to solve this puzzle. On the first day of November 1879, Victor Zepherinus Barthelemy filed a homestead claim in the LaCamas area of Washington Territory, about 15 miles east of Fort Vancouver. He, his wife, and two sons lived in a 300-square-foot cabin that Barthelemy had built in October of that year. The family had only recently traveled to the area from Ohio, where both sons were born and Barthelemy had been raised. Relatives on his wife’s side of the family had already homesteaded in the LaCamas area; Barthelemy selected a parcel immediately adjacent to theirs. Although he was raised in the United States, Barthelemy had been born in France in late 1841 or early 1842 and emigrated with his family to the United States in 1849. On November 7, 1854, Victor’s father, John Barthelemy, received United States citizenship in the common court of Montgomery County, Ohio. As John’s minor son, Victor also was granted citizenship. -
T He T Ualat in a Nd Y Amh Il L V Alleys in N Orthwest O
6 T h e T u a l a t in A n d Y a m h il l V a l l e y s In N o r t h w e s t O r e g o n by Rick Thompson As the largest of the Lake Missoula Floods burst out The massive force of water enlarged the existing stream of the Columbia River Gorge, it filled up the Portland channels forming the Carver, Lake Oswego, and the basin and spilled out into the Clackamas (southeast Oregon City gaps. Eventually the Oregon City Gap, of Portland), Tualatin (west of Portland), Yamhill where the Willamette River runs became the main (southwest of Portland), and Willamette (south of channel for the flood as it filled the Willamette Valley, Portland) Valleys. The floodwaters filled each of these but it would take a while to enlarge the nearly sixmile valleys to almost 400 feet above today’s sea level. long channel enough to handle the flow. The Lake Oswego Gap is almost a direct shot from the mouth of the Columbia River Gorge with few obstacles in its way. The Oregon City Gap is two miles farther from the gorge and has obstacles that would slow the rampaging waters before reaching it. Also, it is narrower and longer than the Lake Oswego Gap further restricting the flow out of the Portland basin. This meant at least at the beginning, the Lake Oswego Gap carried more water than the Oregon City Gap. Figure 1. Location of the Tualatin, Yamhill and Willamette Valleys Figure 3. -
The Missoula Flood
THE MISSOULA FLOOD Dry Falls in Grand Coulee, Washington, is the largest waterfall in the world, but it is currently inactive because it is on an intermittent stream that is not expected to flow again until the next Missoula Flood. Height of falls is 385 ft [117 m]. Flood waters were about 260 ft deep [80 m] above the top of the falls, so a more appropriate name might be Dry Cataract. OVERVIEW In latest Pleistocene time, about 14 000 years ago, glaciers from the Cordilleran ice sheet in Canada advanced southward and dammed andor diverted two rivers, the Columbia River and one of its major tributaries, the Clark Fork River [Fig. 1]. Figure 2—Lakes Columbia and Missoula created by ice dams. Figure 1—Columbia River drainage as the Cordilleran ice sheet advanced southward. The Okanogan lobe of the Cordilleran ice sheet advanced into the Columbia River valley, creating Lake Columbia and diverting the Columbia River into the Grand Coulee. Another lobe of the ice sheet advanced southward down the Purcell Trench to the present Lake Pend Oreille in Idaho and dammed the Clark Fork River. This created an enormous Lake Missoula, about 4½ times the size of Lake Erie [530 mi3 or 2200 km3], that had no outlet [Fig. 2]. When the dammed water got deep enough, it started floating the glacier, and the tremendous surge of water under the ice immediately broke up the ice dam, leading to the cataclysmic dumping of Lake Missoula. A wall of water close to 2000 ft [700 m] high surged through the breached dam and poured across eastern Washington at speeds of up to 100 mph [45 m/s]. -
Lower Grand Coulee
Ellensburg Chapter Ice Age Floods Institute Lower Grand Coulee Field Trip Leader: Karl Lillquist, Geography Department, CWU 8 November 2015 1 Preliminaries Field Trip Overview The Lower Grand Coulee extends from Dry Falls to Soap Lake. It is perhaps the most striking of the coulees of the Missoula Flood-created Channeled Scablands. We will explore saline lakes, ice age lakes, hanging valleys, flood bars, giant current ripples, folded Columbia River Basalts, butte and basin topography, potholes, caves, rhino casts, and human activity related to the ice age floods in the Lower Grand Coulee. Stops will include the Ephrata Expansion Bar south of Soap, Soap Lake (a closed basin lake at the downstream end of the Lower Grand Coulee), a flood bar covered with giant current ripples at the mouth of East Lenore Coulee, Lake Lenore caves (notable as models of human occupation sites in the area), and Dry Falls at the head of the coulee. Tentative Schedule 9:00 am Depart CWU 10:30 Stop 1—Ephrata Expansion Bar 11:15 Depart 11:30 Stop 2—Soap Lake (inc. restroom) 12:15 pm Depart 12:30 Stop 3—East Lenore Coulee Bar 1:30 Depart 1:45 Stop 4—Lake Lenore Caves (inc. pit toilet) 3:15 Depart 3:30 Stop 5—Dry Falls (inc. restroom) 4:15 Depart 6:00 Arrive at CWU Figure 1. Relative bearings using a clock. Assume that your automobile is always pointed to 12 o’clock. Source: Campbell (1975, 2 p. 1). Our Route & Stops Figure 2. Our route shown with arrows and stops noted with numbers. -
Gorge Geology Presentation
Columbia Gorge Geology and the Ice Age Floods Columbia River Gorge Near Perfection... And Only 40+ Million Years in the Making Lloyd DeKay, Ice Age Floods Institute - Columbia Gorge Chapter GorgeFloods.org Geologic Time If 1 MY = 1” Dinosaurs Gone = 65in Columbia River trough = ~50in Columbia River = 20in Columbia River Basalt = 17.5-14in Ice Age Floods = .018in Earth formed = 125yd BIG BANG = 1/4mi Geology has a very long time to do its work ~50-20 MYA – Oldest Gorge Records An offshore volcanic arc, west of present-day Cascades, spewed ash eastward toward John Day Fossil Beds John Day Fossil Beds National Monument Proto-Cascades 50-20 MYA John Day Area ~30 MYA Volcanic ash from these proto-Cascade volcanos blowing eastward repeatedly buried the John Day area, preserving the world's most complete record of Miocene life Meanwhile weathered volcanic debris washed down the arc flanks into the Columbia trough Eagle Creek Debris John Day Fossil Beds Natl Monument Flow ~20MYA Columbia River Basalt 17.5-6 MYA About 17.5 MYA volcanism shifted east to the Idaho border area, burying the Columbia Basin in 1000’s of feet of basalt There were over 300 MASSIVE fissure eruptions that poured extremely fluid basalt from 20,000 vents, up to 30' wide and 10mi long • They covered 81,100mi2 to 16,000' thick • Could cover Cont. US 12'+ thick • 90% erupted in first 2 MY • 21 poured thru Columbia River “Gorge” • Flowed at up to 9mph • Took ~1 week to the coast Local Columbia River Basalt Features Stacked Basalt Layers – Horsethief Butte Basalt Arch – Catherine -
The Channeled Scabland: a Retrospective
ANRV374-EA37-17 ARI 27 March 2009 15:25 The Channeled Scabland: A Retrospective Victor R. Baker Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona 85721-0011; email: [email protected] Annu. Rev. Earth Planet. Sci. 2009. 37:393–411 Key Words First published online as a Review in Advance on catastrophism, floods, fluvial erosion, megaflooding, uniformitarianism December 30, 2008 by University of Nevada - Las Vegas on 10/24/11. For personal use only. The Annual Review of Earth and Planetary Sciences is Abstract online at earth.annualreviews.org The Channeled Scabland of east-central Washington in the United States This article’s doi: Annu. Rev. Earth Planet. Sci. 2009.37:393-411. Downloaded from www.annualreviews.org is a complex of anastomosing rock-cut fluvial channels, cataracts, loess is- 10.1146/annurev.earth.061008.134726 lands, rock basins, broad gravel deposits, and immense gravel bars. In the Copyright c 2009 by Annual Reviews. 1920s, J Harlen Bretz demonstrated that the Channeled Scabland formed by All rights reserved cataclysmic erosion and deposition from Pleistocene megaflooding derived 0084-6597/09/0530-0393$20.00 from the margins of the Cordilleran Ice Sheet, particularly glacial Lake Mis- soula in western Montana and northern Idaho. Studies of this region and the high-energy flood processes that generated it are stimulating (a) discover- ies of similar megaflood-related landscapes around the world and on Mars, (b) enhanced understanding of the processes involved in the fluvial erosion of bedrock, and (c) the use of paleoflood indicators for understanding the magnitudes and frequency of flooding.