Geology topics
Source-linked reports with geographic coverage including Oregon, Washington.
Volcanic glass in marine sediments off Oregon and Washington correlates with continental deposits of Mount Mazama ash by stratigraphic position, refractive index, and radiocarbon dating. Ash deposited in the abyssal regions by turbidity currents is used for tracing of the dispersal routes of postglacial sediments and for evaluation of marine sedimentary processes.
The disposition of radionuclides in and along the 380-mile reach of the Columbia River between the Hanford, Wash., Atomic Energy Commission reactors (the major radionuclide source) and the head of the estuary is a first step in understanding the environmental cycling and ultimate fate of the discharged radioactive materials. Preliminary results for the study period, July 1962 to September 1963, are presented for radionuclide, sediment, and water data from stations on the Columbia River and from stations near the mouths of the Snake River, the Willamette River, and other Columbia River tributaries.
The nuclides zinc-65 and cobalt-60 associated with river-borne particulate matter are incorporated in sediment on the Continental Shelf near the Colum- ia River. Changes in the relative concentrations of zinc-65 and cobalt-60 and in the ratio of the activity of zinc-65 and cobalt-60 suggest that radioactive sediment moves northward 12 to 30 kilometers per year along the shelf and 2.5 to 10 kilometers per year westward away from the coast.
New petrographic and chemical data indicate that the great Mount Mazama eruption at Crater Lake, Oregon, about 6600 years ago was the source of most ash which has been called "Glacier Peak" and of some ash called "Galata." Glacier Peak volcano in Washington was itself the source of an older ash deposit, perhaps very late glacial or early postglacial in age.
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During the histological examination of a group of wild and hatchery salmonids undescribed sporazoans were frequently observed. This was not unexpected, since Myxosporidia are typical fish parasites (Kudo, 1920). Myxidium were observed in kidney tubules, Cholromyxum in glomeruli, and Myxobous in the spinal cord and on epidermal scales. The present paper will deal with the description and indentification of these unclassified Myxosporodia.
During the histological examination of a collection of wild and hatchery salmonids, a peculiar foreign body was occasionally observed in various organs, particularly in the viscera. These objects, usually accompanied by a focal inflammation, were observed in 10 of 75 samples of wild trout and salmon collected in Oregon and Washington and were believed to represent an unknown type of parasitism. Their identity remained obscure until a massive concentration was observed in the tissues of wild coho salmon, ( Oncorhynchus kisutch ), from Minter Creek on the Olympic peninsula of Washington and in hatchery coho salmon from the Minter Creek Biological Station. The distribution of the structures suggested the intestinal tract as a point of origin. Subsequent stomach examinations revealed small, partially digested insect fragments with many long, spine-covered hairs. The insects were identified as second or third instars of the lepidopteran larvae, Halisidota argentata Packard. The spine-covered hairs penetrated the stomach wall and produced the observed lesions by working in an apparent porcupine quill-fashion throughout the body of the fish. The pathology of the Minter Creek salmon was sufficiently extensive to merit a description of the condition for the benefit of other workers who may encounter this rather unusual phenomenon and confuse it with an actual parasitic infection.
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The Columbia River is the largest stream in western United States. Above The Dalles, Oregon, it drains an area of 237,000 square miles, of which 39,000 square miles is in Canada. This area is largely mountainous and lies between the Rocky Mountains and the Cascade Range. The Kootenai, Pend Oreille, and Snake Rivers are the principal tributaries. Precipitation varies from 7 inches near Kennewick, Wash. to over 100 inches in some of the mountainous regions. Most of the runoff occurs in the spring and summer months as a result of melting snow. Precipitation is generally light during the summer months, and irrigation is necessary for sustained crop production. Historical data indicate that irrigation in the Columbia River basin began prior to 1840 at the site of missions established near Walla Walla, Wash. and Lewiston, Idaho. During the next half century the increase in irrigated area was slow and by 1890 included only 506,000 acres. The period 1890 to 1910 was marked by phenomenal increase to a total of 2,276,000 acres in 1910. Since that time there has been more gradual addition to a total of 4,004,S00 acres of irrigated land in 1946 in the Columbia River basin above The Dalles, Oreg. Of this total 918,000 acres were located in the Columbia Basin above the mouth of the Snake River; 2,830,000 acres in the Snake River basin, and the balance, 256,000 acres below the mouth of the Snake River. Values of net consumptive use were determined or estimated for various tributary basins of the Columbia River basin and compared to available experimental data. These values were then used to compute the average depletion which could be directly attributed to irrigation. The yield of a drainage basin was considered to be the rum of the ob- served runoff and the estimated depletion. For purposes of comparison, the depletion was expressed both in terms of acre-feet and as a percentage of the yield of the basin. This percentage depletion varied from less than 1 percent for many tributary basins to 53 percent for the portion of the Snake River basin between Heise and King Hill, Idaho. For the Columbia River near The Dalles, Oreg., the average depletion during the period 1921 through 1945, amounted to 4,7 percent of the yield and the depletion represented by the 1946 stage of irrigation development amounted to 5.3 percent of the long-term yield.
THE year 1941 was a crucial one for the blueback salmon of the Columbia River. During that year, one brood came closer to extinction than was realized by more than a few individuals. The immediate causes were not overfishing, hydroelectric power development, or irrigation—although these factors continued to exert their long-standing effects. The direct causes can be attributed to an “act of God” plus—in large measure--lack of knowledge concerning the basic principles of effective artificial propagation. With the security and assurance provided by subsequent developments, those concerned with the Columbia River blueback salmon may be interested in a brief recapitulation of events that transpired during the early 1940s. This particular piece of fishery history bears upon the problems of the immediate future on the Columbia River.