Kalama Narrows EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(other)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
A Bretz Flood Earthcache
The Port of Kalama is kind enough to allow this Earthcache in their park. Please observe all rules as all good cachers do. It is a beautiful well maintained day park and it has a covered picnic area that you can apply to use. The park would make a great cache event place. Plan to spend some time in the park and the town of Kalama. I had a wonderful afternoon visiting the city of Kalama. I walked the main street and found it has good restaurants and lots of antiques malls and other interesting stores. You are at the start of the Kalama Narrows and the narrowest part is down river. Straight across the river is Sandy Island. To validate this cache go to the above coordinates and email me your answers to the 3 questions 1. Tell me what the subject of the sign at the above coordinates. I am sorry the sign disappeared, so disregard this question! 2. Estimate the width of the river to the island. 3. Look NW and estimate the width of the Narrows, remember the flood was 400 feet high through the narrows. Feel free to post a picture of you and the special poles north of the sign. When Glacial Lake Missoula was measured in the 1920’s by Pardee he estimated the maximum lake volume to be about 500 cubic miles. This was arrived by Pardee walking all of the mountains and hills to find the upper level boundaries of the Lake. Pardee then had to mathematically compute the volume of water. Remember it was done with pencil and paper. In the middle of 1980’s scientist using forest service and topographic maps along with satellite pictures estimated the lake to be 540 cubic miles in volume. Amazingly, Pardee only missed it by 8%. Now 540 cubic miles does not compute to my brain, it is just a number. So I broke it down to something I could relate to. 500 cubic miles of water would make a lake from the mouth of the Columbia to San Diego 10 miles wide and 260 feet deep. That is a lot of water!! This huge amount of water tried to go through some of the narrow points along the way to the Pacific and was temporarily backed up. The flood backed up in 3 narrows and made temporary lakes. Here is a summary of the choke points and the lakes they produced. The figures are a summary of the 3 authors cities below. Wallula Gap is SE of the tri-cities and it produced Lake Lewis (see picture) which covered the tri-cities, Yakima Valley, Walla Walla Valley and up to 100 miles of the Snake River towards the east. Lake Lewis was 1,000 feet above the valley floor and covered 3,000 sq miles. The Columbia Gorge had several narrows and they produced Lake Condon (see picture) and went from Wallula Gap to the exit of the gorge by Troutdale. Lake Condon was 1,000 feet above river bed and covered 1,500 sq miles. The Kalama Narrows was the last choke point in the Bretz flood and produced the largest lake. As the flood exited the gorge it was 500 feet high and most went west but some started forming Lake Allison. As the flood came to Kalama Narrows it was backed up to about 400 feet high and about 20% of the flood water backed up to formed Lake Allison (see picture). Lake Allison covered from the mouth of the gorge to Kalama Narrows and south to Eugene and covered the Vancouver plains 35 miles to the north. Lake Lewis filled very rapidly and covered 11,000 sq miles up to 400 feet deep. All of the above lakes filled in a few days but probably emptied in a week or so. Previous glacial advances and retreats left a southern moraine about where Highway 2 leaves Spokane and goes west almost to the Cascade Mountains. This moraine formed a southern dam for Lake Columbia (see picture). On the east boundary was Rathdrum Prairie at a depth of 200+ feet deep, it covered Spokane over 300+ feet. To the west it covered Grand Coulee to a depth of 800+ feet deep. Scientists now believe this lake was not temporary, but a lake that form to drain the massive amounts of melt waters from the glaciers. Lake Columbia flowed gently over what is now Dry Falls at the south end of Grand Coulee until it froze in the winter. The flow was never big enough to do much erosion to Dry Falls but it had to be spectacular with the big drop and a nice plunge pool. When the Flood came to Dry Falls it eroded the lip and moved the falls back up stream. There is one last chapter of the Flood and that is Astoria Canyon (see picture). Since there was an ice age the mouth of the Columbia extended 40 miles west of its present mouth and the oceans were 300 feet shallower. Thanks to Google Earth one can see where the Columbia River has carved out the Astoria Canyon over eons and eons. The annual silt and migration of sand has filled the river bed from the present mouth to the start of the canyon. During the Flood era you would have been able to see the Columbia River Channel to the Astoria Canyon. The canyon starts 11 miles west of the mouth of the Columbia River and is 330 feet deep at that point. The canyon crosses the continental shelf and ends at a depth of 6,840 feet deep. The width is from 1.5 to 8.3 miles and is 75 miles long. The deepest part of the canyon is 3,000 feet which is about 3 times the depth of the present Columbia Gorge. The end of the canyon has a sediment fan that is 70 miles long. I am sure the Bretz flood had a partial hand in carving out part of the Astoria Canyon. References Cataclysms on the Columbia by Allen & Burns Glacial Lake Missoula by David Alt Ice Age Floods by Bruce Bjornstad Academic Dictionaries and Encyclopedias Google Earth
Additional Hints
(Decrypt)
Oevat lbhe gblf naq cynl va n ornhgvshy naq pyrna cnex.
Treasures
You'll collect a digital Treasure from one of these collections when you find and log this geocache:
Loading Treasures