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R. W. Page

Publications and source records attributed to R. W. Page.

18 recordsLinked to original sources
USGS1984

Ground-water conditions and well yields in fractured rocks, southwestern Nevada County, California

This report describes the availability of ground water in the southwestern part of Nevada County, and suggests general guidelines for selecting sites for future ground-water development in the study area. Ground water in this area occurs chiefly in fractures in hard pre-Tertiary metavolcanic and plutonic rocks generally above a depth of 215 feet. Some ground water is found at the contact between alluvium or decomposed granite and the underlying hard rock; little is found in alluvium or colluvium. Mean yield is less than 18 gallons per minute. (USGS)

Water-Resources Investigations Report↗
USGS1983

Data for ground-water test hole near Nicolaus, Central Valley aquifer project, California

Preliminary data are provided for the third of seven test holes drilled as a part of the Central Valley Aquifer Project which is part of the National Regional Aquifer Systems Analysis Program. The test hole was drilled in the SW 1/4 NE 1/4 sec. 2, T.12N., R.3E., Sutter County, California, about 1 1/2 miles northwest of the town of Nicolaus. Drilled to a depth of 1,150 feet below land surface, the hole is cased to a depth of 100 feet and equipped with three piezometer tubes to depths of 311, 711, and 1,071 feet. A 5-foot well screen is set in sand at the bottom of each piezometer. Each screened interval has a cement plug above and below it to isolate it from other parts of the aquifer, and the well bore is filled between the plugs with sediment. Thirty-one cores and 34 sidewall cores were recovered. Laboratory tests were made for minerology, consolidation, grain-size distribution, Atterberg limits, X-ray diffraction, thermal conductivity, and chemical analysis of water. Geophysical and thermal gradient logs were made. The hole is sampled periodically for chemical analysis of the three tapped zones and measured for water level. This report presents methods used to obtain field samples, laboratory procedures, and the data obtained. (USGS)

Open-File Report↗
USGS1982

Data for ground-water test hole near Zamora, Central Valley Aquifer Project, California

Preliminary data are presented for the first of seven test holes drilled as a part of the Central Valley Aquifer Project which is part of the National Regional Aquifer Systems Analysis Program. The test hole was drilled in the SW 1/4 SE 1/4 sec. 34, T. 12 N. , R. 1 E., Yolo County, California, about 3 miles northeast of the town of Zamora. Drilled to a depth of 2,500 feet below land surface, the hole is cased to a depth of 190 feet and equipped with three piezometer tubes to depths of 947, 1,401, and 2,125 feet. A 5-foot well screen is at the bottom of each piezometer. Eighteen cores and 68 sidewall cores were recovered. Laboratory tests were made for mineralogy, hydraulic conductivity, porosity , consolidation, grain-size distribution, Atterberg limits, X-ray diffraction, diatom identification, thermal conductivity, and chemical analysis of water. Geophysical and thermal gradient logs were made. The hole is sampled periodically for chemical analysis and measured for water level in the three tapped zones. This report presents methods used to obtain field samples, laboratory procedures, and the data obtained. (USGS)

Open-File Report↗
USGS1980

Ground-water conditions at Beale Air Force Base and vicinity, California

Ground-water conditions were studied in a 168-square-mile area between the Sierra Nevada and the Feather River in Yuba County, Calif. The area is in the eastern part of the Sacramento Valley and includes most of Beale Air Force Base. Source, occurrence, movement, and chemical quality of the ground water were evaluated. Ground water occurs in sedimentary and volcanic rocks of Tertiary and Quaternary age. The base of the freshwater is in the undifferentiated sedimentary rocks of Oligocene and Eocene age, that contain water of high dissolved-solids concentration. The ground water occurs under unconfined and partly confined conditions. At Beale Air Force Base it is at times partly confined. Recharge is principally from the rivers. Pumpage in the study area was estimated to be 129,000 acre-feet in 1975. In the 1960's, water levels in most parts of the study area declined less rapidly than in earlier years or became fairly stable. In the 1970's, water levels at Beale Air Force Base declined only slightly. Spacing of wells on the base and rates of pumping are such that excessive pumping interference is avoided. Water quality at the base and throughout the study area is generally good. Dissolved-solids concentrations are 700 to 900 milligrams per liter in the undifferentiated sedimentary rocks beneath the base well field. (USGS)

Open-File Report↗
USGS1977

Appraisal of ground-water conditions in Merced, California, and vicinity

Merced is in the northeastern part of the San Joaquin Valley, California. The fresh-ground-water basin is about 1,200 feet thick. Five aquifers are defined in the Merced area: (1) The Mehrten Formation (Miocene and Pliocene), (2) a confined aquifer , (3) an intermediate aquifer, (4) a shallow aquifer, and (5) a probable unconfined aquifer. Ground water moves generally westward or southwestward. Recharge to the aquifers is from ground-water flow, leakage, and irrigation water. Discharge is by seepage, evaporation, transpiration, and pumping. Fluctuations in water level vary from place to place. The chemical quality of ground water is good and is generally a bicarbonate-type water.

California↗
USGS1977

Guide for data collection to calibrate a predictive digital ground-water model of the unconfined aquifer in and near the city of Modesto, California

The city of Modesto encompasses about 12 square miles in the northeastern part of the San Joaquin Valley, Calif. The ground-water model encompasses about 542 square miles. In the Modesto area, ground water occurs in an unconfined aquifer a confined aquifer. both of which are composed of unconsolidated materials, and a consolidated-rock aquifer. Only the unconfined aquifer was modeled, using several simplifying assumptions concerning hydrologic conditions in the ground-water basin. A program is used that computes the net rate of recharge and discharge under steady-state conditions. The model was then modified until reasonable values of recharge and discharge were computed. Testing of the model indicated that simulated water levels were especially sensitive to tansmissivity, storage coefficient, irrigation return, and riverbed hydraulic conductivity; amond the parameters that affected water levels least were the vertical hydraulic conductivity and specific storage of the confining bed, the so-called E-clay. (Woodard-USGS)

California↗
USGS1974

Base and thickness of the Post-Eocene continental deposits in the Sacramento Valley, California

The Sacramento Valley, which forms most of the northern one-third of the Central Valley, is a broad structural trough. The study area comprises the valley floor and some of the foothills of the Sierra Nevada and the Coast Ranges, a total area of about 6,000 square miles. Beneath most places in the valley, the base of the post-Eocene continental deposits is equivalent to the base of the Tehama Formation of Pliocene age, which in some places at least may be of late Oligocene and early Miocene age. The deposits consist of intercalated beds of gravel, sand, silt, clay, tuff, conglomerate, sandstone, siltstone, and claystone. And beneath large areas along the eastern side of the valley the deposits consist of basaltic and andesitic mudflows, tuff, tuff breccias, volcanic sandstones and conglomerates, and sand and gravel, as well as overlying nonvolcanic sediments. They contain most of the fresh ground water in the valley. The structure of the base of the continental deposits is that of a large northward-trending syncline whose trend is interrupted only by the Sutter Buttes. In the subsurface, faulting has occurred mostly within the basal part of the deposits. Beneath the northeastern part of the valley, along the Chico monocline, faulting has occurred through probably the total thickness of the deposits. The deposits range in thickness from zero near the margins of the valley to about 3,500 feet beneath the south-central part of the valley. The thickest sections occur along the axis of the syncline, but near Sutter Buttes the deposits are thinner than at any other locale near the central part of the valley.

California↗
USGS1973

Geology and quality of water in the Modesto-Merced area, San Joaquin Valley, California, with a brief section on hydrology

The Modesto-Merced area includes about 1,800 square miles on the northeast side of the San Joaquin Valley. The physiographic units in the area are (1) Sierra Nevada, (2) dissected uplands, (3) low alluvial plains and fans, (4) river flood plains and channels, and (5) overflow lands. Geologic units consist of consolidated rocks and unconsolidated deposits. The dominant structure of the geologic units is that of a homocline, which reflects the southwestward-tilted fault block of the Sierra Nevada. The consolidated rocks include: (1) basement complex (pre-Tertiary), (2) marine sandstone and shale (Cretaceous), (3) Ione Formation and other sedimentary rocks (Eocene), (4) Valley Springs Formation (late? Miocene), and (5) the Mehrten Formation (Miocene and Pliocene). In the eastern part of the area, the consolidated rocks generally yield small quantities of water to wells except for the Mehrten Formation which is an important aquifer. The unconsolidated deposits include: (1) continental deposits (Pliocene and Pleistocene?), (2) lacustrine and marsh deposits (Pleistocene), (3) older alluvium (Pleistocene and Holocene?), (4) younger alluvium (Holocene), and (5) flood-basin deposits (Holocene). The continental deposits and older alluvium are the main water-yielding units in the unconsolidated deposits. The lacustrine and marsh deposits (E-clay) and the flood-basin deposits yield little water to wells, and the younger alluvium in most places probably yields only moderate quantities of water to wells. There are three ground-water bodies in the Modesto-Merced area: (1) the unconfined water body, (2) the confined water body, and (3) the water body in consolidated rocks. The unconfined water body occurs in the unconsolidated deposits above and east of the E-clay, except in the western and southern parts of the area where clay lenses occur and semiconfined conditions exist. The confined water body occurs in the unconsolidated deposits below the E-clay and extends downward to the base of fresh water. The water body in consolidated rocks occurs under both perched and confined conditions. Ground-water movement in the unconfined and the confined water bodies is generally westward toward the valley trough. In the unconfined water body, the water also moves toward the major rivers, and toward pumping depressions at Modesto and near El Nido. Because of the higher head in the unconfined water body, water slowly moves from it through the E-clay to the underlying confined water body. Surface water is used extensively for irrigation in most of the study area; consequently, shallow water in the unconfined water body has to be controlled by pumping. Nevertheless, water levels near Modesto declined about 6 feet between 1958 and 1962, for the most part during the dry years 1959-61. Near El Nido, water levels declined about 70 feet between 1942 and 1967. In the confined water body, water levels were high in the winter and spring and low in the summer and fall, reflecting irrigation practices. In the southwestern part of the area, water levels in the confined water body declined about 14 feet from 1962 to 1968 and rose slightly after 1968, whereas in the northwestern part water levels remained fairly constant. Water from the upper reaches of the Stanislaus, Tuolumne, Merced, and Chowchilla Rivers is calcium bicarbonate in chemical type and is of excellent quality. As those rivers cross the valley floor, their water quality is generally degraded by return flows from irrigated land, and in the Tuolumne River by saline water discharged from abandoned gas wells. Average dissolvedsolids content in the major rivers, as indicated by chemical analyses, do not exceed 400 mg/1 (milligrams per liter) except in the San Joaquin River where average dissolved-solids content has not exceeded 1,050 mg/l. Water from minor streams in the area is bicarbonate in chemical type with dissolved-solids content ranging from 56 mg/1 to about 350 mg/l. Although chloride-type fresh ground water occurs in the unconfined and confined water bodies and in the water body in consolidated rocks, most of the fresh ground water is a bicarbonate type that has a dissolved-solids content of less than 500 mg/l. Water having dissolved solids in excess of about 2,000 mg/1 is considered to be saline. Saline water extends below the base of fresh water to the basement complex and, except in the extreme eastern part, underlies most of the study area. Saline water also occurs as lenses above the base of fresh water in the unconfined and confined water bodies.

California↗
USGS1971

Data for wells in the Modesto-Merced area, San Joaquin Valley, California

The Modesto-Merced area is in the northeastern part of the San Joaquin Valley. The area includes about 1,800 square miles that lie in the eastern portions of Merced and Stanislaus Counties. Specifically the boundaries are: North, the Stanislaus River; south, the Merced-Madera County line; east, the Merced-Mariposa and the Stanislaus-Tuolumne County lines; west, the San Joaquin River. Between September 1970 and May 1971, 859 wells were selectively canvassed in the area. The resulting data are on file in the U.S. Geological Survey office at 2800 Cottage Way, Sacramento, Calif. Selected well data are tabulated in table 1, and the location of these wells is shown on maps 1-65. Selected chemical analyses are shown in table 2. Table 3 is a listing of the well numbers of all wells canvassed in the area by the U.S. Geological Survey through April 1971.

California↗
USGS1960

Data on water wells, Naval Air Missile Test Center Area, Point Mugu, California

The entire water supply for the U. S. Naval Air Missile Test Center at Point Mugu, Calif., is pumped from wells located .within 2 miles of the Pacific Ocean. A large irrigation development inland from the Test Center has created a landward hydraulic gradient beneath the Test Center, causing sea-water encroachment into the water-yielding deposits. The encroaching sea water has not yet reached the Test Center well field; however, the encroachment poses a serious threat to the Test Center supply. To evaluate the adequacy of the water supply for the Naval Air Missile Test Center under these conditions and to suggest additional sources for future development, the U. S. Geological Survey has canvassed all wells and collected all available hydrologic dataat the Test Center and in the immediate vicinity. The data tabulated in this report include measurements of water levels in wells, well logs, and chemical analyses for all wells south of Hueneme Road collected through February 1959. This study was made by the Geological Survey, U. S. Department of the Interior, under the general supervision of H. L. Wilson, Jr., district engineer for California, and under the immediate supervision of Fred Kunkel, geologist in charge of the Long Beach subdistrict office.

California↗