Gorge Geology: History Forum series begins Feb. 1

White Salmon resident Terry Hurd will address the geology of the Columbia River Gorge Saturday, Feb. 1, in the first of four Regional History Forum programs at the Original Wasco County Courthouse, 410 W. Second Place, The Dalles. The program, entitled “Gorge Geology: Colliding Plates, Lava Flows and the Missoula Flood,” begins at 1:30 p.m.

The program takes place in the upstairs courtroom of the 1859 building. There is a TV monitor to the downstairs sheriff’s office to accommodate those unable to climb the stairs. Coffee and cookies will be served after the program.

Hurd is president of the Columbia River Gorge Chapter of the Ice Age Floods Institute. He is a retired fisheries biologist and amateur geologist. His PowerPoint program includes photos of nearby geologic features as well as the locations of glaciers and the ice dams that failed, resulting in catastrophic floods that forever altered our surroundings, scouring the valley with 500 cubic miles of water and massive blocks of ice.

Eighteen million years ago the area of the Gorge was a 40-mile-wide lowland. A collection of streams draining from the central Washington plateau joined and flowed west to the Pacific Ocean forming the ancestral Columbia River. About that time the North American tectonic plate was overlying a hot spot now underlying Yellowstone National Park.

Over the next 12 million years or so lava flows from deep fissures in the earth’s surface near the Washington-Idaho-Oregon border erupted and spread rapidly across thousands of square miles and to the Pacific Ocean. This event occurred more than 300 times.

During the same time period the North American continent continued to slowly move to the southwest. Its collision with the Farallon and Juan de Fuca oceanic plates pressing in the opposite direction caused the continental crust to buckle and fracture. The resulting folds played a major role in the location of the Columbia River Gorge and the later glacial-outburst floods from Lake Missoula.

Between 18,000 and 15,000 years ago a lobe of the Cordilleran ice sheet repeatedly formed an ice dam in the Purcell Trench of northern Idaho. These 2,500-plus-foot high dams blocked the mouth of the Clark Fork River, backing up a 3,000-square-mile and 2,000-foot-deep lake, Glacial Lake Missoula.

As the lake waters rose they eventually floated and hydraulically undermined the dam until it suddenly failed catastrophically, releasing 500 cubic miles of glacial melt water and massive blocks of glacial ice.

These huge floods, about 100 in number, flowed at rates of 10 times the combined flow of all of the current rivers of the world, draining the lake in a matter of days. The flood waters reached the Gorge in about 10 days, forever altering its features.

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Parkdale third graders sing "12 Disaster Days of Christmas"

Welcome to your sing-able Christmas gift list. What follows is an emergency rendition of “12 Days of Christmas” – for outfitting your home or car in case of snow storm, earthquake, flood or other emergency. Read it as a simple list, or sing it to the tune of “12 Days” – you know, as in “ … and a partridge in a pear tree…” Not to make light of it, but the song is a familiar framework for a set of gift ideas that you could consider gathering together, even if the recipient already owns items such as a bunch of coats, tire chains and flashlights. Stores throughout the Gorge are stocked up on all these items. Buying all 12 days might be prohibitive, but here are three ideas for checking any of the dozen off your list (notations follow, 1-12.) The gift items needed to stay warm, dry and safe are also coded to suggest items in your abode (A) in your car (C) or both (B). 12 Gallons of Water (A) 11 Family meals (B) 10 Cans of propane (A) 9 Hygiene bags (B) 8 Packs of batteries (A) 7 Spare coats (B) 6 Bright red flares (C) 5 Cozy blankets (B) 4 Tire chains (C) 3 Flashlights (B) 2 cell phone chargers (B) 1 And a crush-proof first aid kit (B) Price ranges? Here’s a few quotes for days Three, Two, Four and Nine: n A family gift of flashlights (three will run $15-30, Hood River Supply, Tum-A-Lum) n Cell phone chargers (two will run $30-60) n Tire chains (basic set, $30, Les Schwab, returnable if unused for the winter) n Family meals ($100 or so should cover the basics for three or four reasonably well-fed days) n The home kit should be kept in a handy place near an exit, and remember that water needs to be replenished every few months. If you have a solid first aid kit already, switch out the gift idea with “and-a-sto-o-u-t- tub-for it-all …” Otherwise, it’s a case of assembling your home or car kits and making sure all members of the family know what the resources are and how to use them (ie flares and propane). Emergency situations are at worst life-threatening, at best deeply uncomfortable if you and your family are left without power for an extended period, or traveling and find yourself in a situation where you need to wait out a storm, lengthy traffic delay, or other crisis. Notes on the 12 gift ideas: 12 – Gallons of water: that’s one per person in a four-member family to last for three days, the recommended minimum to be prepared for utility outages. 11 – Easy-open packaged goods, energy bars, dried food and nuts are good things to include for nutrition. Think of what your family of four needs for three days to stay fortified and hydrated (see number 12). Can-opener also recommended 10 – If you have a propane camping stove, keep extra fuel handy. 9 – Hygiene bags: put packaged moistened towelettes, toilet paper, and plastic ties in large garbage bags (for personal sanitation) Resource list courtesy of Hood River County Emergency Management, Barbara Ayers, manager/ 541-386-1213. The county also reminds residents to Get a Kit, Make A Plan to connect your family if separated, and Stay Informed. See www.co.hood-river.or.us to opt-in for citizen alerts. Enlarge



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