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R. C. Newcomb

Publications and source records attributed to R. C. Newcomb.

At least 19 recordsLinked to original sources
USGS1965

Water for Oregon

Explore the source record for details and available documents.

Water Supply Paper↗
USGS1965

Geology and ground water of the Tualatin Valley, Oregon

The Tualatin Valley proper consists of broad valley plains, ranging in altitude from 100 to 300 feet, and the lower mountain slopes of the drainage basin of the Tualatin River, a tributary of the Willamette River in northwestern Oregon. The valley is almost entirely farmed. Its population is increasing rapidly, partly because of the expansion of metropolitan Portland. Structurally, the bedrock of the basin is a saucer-shaped syncline almost bisected lengthwise by a ridge. The bedrock basin has been partly filled by alluvium, which underlies the valley plains. Ground water occurs in the Columbia River basalt, a lava unit that forms the top several hundred feet of the bedrock, and also in the zones of fine sand in the upper part of the alluvial fill. It occurs under unconfined, confined, and perched conditions. Graphs of the observed water levels in wells show that the ground water is replenished each year by precipitation. The graphs show also that the amount and time of recharge vary in different aquifers and for different modes of ground-water occurrence. The shallower alluvial aquifers are refilled each year to a level where further infiltration recharge is retarded and water drains away as surface runoff. No occurrences of undue depletion of the ground water by pumping are known. The facts indicate that there is a great quantity of additional water available for future development. The ground water is developed for use by some spring works and by thousands of wells, most of which are of small yield. Improvements are now being made in the design of the wells in basalt and in the use of sand or gravel envelopes for wells penetrating the fine-sand aquifers. The ground water in the basalt and the valley fill is in general of good quality, only slightly or moderately hard and of low salinity. Saline and mineralized water is present in the rocks of Tertiary age below the Columbia River basalt. Under certain structural and stratigraphic conditions this water of poor quality contaminates the fresh-water aquifers. Detailed hydrologic and geologic conditions are presented in 5 tables, 7 pictures, and 17 graphic figures and plates.

Water Supply Paper↗
USGS1965

Geology and ground-water resources of the Walla Walla River basin Washington-Oregon

The Walla Walla River, whose drainage basin of about 1,330 square miles lies astride the Washington-Oregon boundary, drains westward to empty into the Columbia River. The basin slopes from the 5,000-foot crest of the Blue Mountains through a structural and topographic basin to the terraced lands adjoining the Columbia River at an altitude of about 340 feet. The main unit of the topographic basin is the valley plain, commonly called the Walla Walla Valley, which descends from about 1,500 feet at the foot of the mountain slopes to about 500 feet in altitude where the river cuts through the bedrock ridge near Divide. In the Blue Mountains the streams flow in rockbound canyons. Beyond the canyons, near Milton-Freewater and Walla Walla, they pass onto the broad alluvial fans and the terrace lands of the valley.

Washington, Oregon↗
USGS1959

Some preliminary notes on the ground water in the Columbia River basalt

The Columbia River basalt carries ground water by percolation, largely along tabular interflow zones of variable permeability and continuity. At various places the water occurs under perched, unconfined, and confined conditions; at some places it occurs under all three conditions at different depths. Both initial and tectonic structural features, such as inclination of the flows, anticlines and synclines, and jointing and faulting, have an important bearing on occurrences of ground water in the basalt . Recharge of the ground water is most effective in areas of substantial rainfall where gravel-bedded streams cross basalt flows inclined at low angles. The basalt furnishes the main water supply for domestic and public needs and a substantial part of the water for irrigation and industry in the Columbia Plateau region. The chemical quality of the ground water is good but varies according to the geographic and geologic occurrence of the basalt rocks. The ground water is developed by thousands of wells and springs. These fall into more or less distinct types according to their construction and the occurrence of the water. There is need for improvement in techniques of construction of wells tapping confined and perched water bodies. Continued accumulation of basic geologic information is planned to guide in further development of the ground-water resources of the basalt.

Northwest Science↗
USGS1957

Ground water of the Columbia Basin

Part of the water that infiltrates from the surface reaches a zone of saturation whence it percolates toward the outlet and thereby is delayed in its course to the sea. This ground water is one form of natural storage which has different degrees of effect on stream flow in different segments of the Columbia River basin. As a whole the Columbia River receives a substantial part of its base flow from the discharge of ground water. The inflow from ground water differs materially in each of the six general terrain areas, which are described briefly below.

Alberta, British Columbia, Idaho, Montana, Oregon,↗
USGS1953

Seismic cross sections across the Spokane River valley and the Hillyard Trough, Idaho and Washington

Two seismic cross sections were run with a refraction seismograph near Spokane, Wash., in Hay and June 1951. One section trended north-south across the Spokane River valley plain Just east of the Idaho-Washington boundary; the other trended east-west across the strath just north of the Hillyard section of Spokane. Each section secured data that permitted the compilation of a graphic cross section showing the position of (1) the water table, (2) the base of the glacial and glaciofluviatile deposits, and (3) the generalized base of the Latah formation and associated deposits (which is the top of the consolidated bedrock). The data confirm the inference of Pardee and Bryan that the granitic bedrock lies at an altitude of about 1,0OO feet beneath the valley plain near the State boundary. The base (a heretofore unlocated feature) of the glacial outwash deposits, the main aquifer of the area, was determined as an uneven plane at an altitude of 1,800 to 1,700 feet in the State-boundary district and at 1,700 feet in the Hillyard Trough district.

Open-File Report↗
USGS1952

Origin of the Mima Mounds, Thurston County region, Washington

There has been recent favorable consideration of the idea that the Mima mounds were made by gophers. The writer believes the evidence indicates that gophers function only in the reworking of the mound material, not in the primary construction. The plausibility of the earlier glacial or periglacial theory has been increased by recent knowledge of permafrost and of the deposits made by combined water and ice in cold climates. The gopher theory, as it has been applied to the Mima mounds, contains internal disharmonies and ignores significant field evidence supporting the earlier idea.

Journal of Geology↗
USGS1951

Ground-water situation in Oregon

The water that occurs beneath the land surface follows definite and well-known rules of hydraulics, the same as water on the surface. However, ground water must be studied by methods, some of which are unique to that type of water occurrence, in order to evaluate the part it plays in the over-all water scheme. Water that falls on the land surface as rain or snow and water that rests upon the surface may in places pass laterally or downward through the pores of the earth materials. There it may take one or more of a variety of paths before again flowing out on the surface or being expelled to the atmosphere by evaporation and by the transpiration of plants. Water so diverted underground is delayed or diverted from its course toward the sea and that digression results in many services of prime importance to mankind. Underground, the water generally exceeds in total quantity the water present on the land surface at any one time. The discussion of ground water can be clarified somewhat by a description of the major parts or phases of the normal path of water underground.

Oregon↗