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Graphs and a table are presented showing the variations in streambed elevations that have occurred over the years in the low-water channels at selected gaging stations in northwestern California. The streambed elevations are calculated from data obtained during discharge measurements. The greatest elevation changes that were recorded occurred between the...

A unique relation between water-surface elevation and water discharge usually does not exist for sand-channel streams. The relation is affected by changes in bed roughness and changes in bed elevation because of scour and fill. An artificial control on a sand-channel stream must control both the resistance to flow and...

The great earthquake that struck Alaska about 5:36 p.m., Alaska standard time, Friday, March 27, 1964 (03:36:1.3.0, Greenwich mean time, March 28, 1964), severely crippled the highway system in the south-central part of the State. All the major highways and most secondary roads were impaired. Damage totaled more than $46...

Properties of sand waves formed by subcritical unidirectional water currents are investigated by statistical analyses of records of streambed profiles. Records of bed elevation y as a function of distance x along the channel, y = y(x), and time records at a fixed point of the channel, y = y(t),...

The great earthquake (Richter magnitude of 8.4–8.5) that struck south-central Alaska at 5:36 p.m., Alaska standard time, on March 27, 1964 (03:36, March 28, Greenwich mean time), was felt in every community on Kodiak Island and the nearby islands. It was the most severe earthquake to strike this part of...

Spur Mountain, Tyee, and Eagle Lakes fill glacially scoured bedrock basins in the Coast Range of southeastern Alaska. The bedrock consists of granitic intrusive rocks and high rank metamorphic rocks associated with or resulting from emplacement of the Coast Range batholith.Spur Mountain damsite is underlain by granodiorite and diorite. The...

The Swatara Creek of the Susquehanna River Basin is the farthest downstream sub-basin that drains acid water (pH of 4.5 or less) from anthracite coal mines. The Swatara Creek drainage area includes 567 square miles of parts of Schuylkill, Berks, Lebanon, and Dauphin Counties in Pennsylvania.To learn what environmental factors...

An uneven erosion surface separates calcareous sedimentary rocks above and vesicular andesite porphyry below at the Guayacan mine of central Chile. Channel-like depressions filled with sedimentary rock flank elongate, stratiform bodies of disseminated copper ore which impregnate the vesicular crests of andesite lava flows. The "channels" lie parallel to and mark the margins of tongues of lava. Erosional features...

The Savannah area consists of about 2,300 square miles of the Coastal Plain along the coast of eastern Georgia and southeastern South Carolina. Savannah is near the center of the area. Most of the large ground-water developments are in or near Savannah. About 98 percent of the approximately 60 mgd...

Progress has been made in describing riverbed scour and fill at a given stream section. One needs only the data routinely collected at a stream-gaging station to observe scour and fill at that station. However, similar progress has not been made to determine whether or not the scour and fill...

During experiments on sediment transport and resistance to flow with a uniform 0.33-mm sand, data were recorded on the movement of individual rocks having intermediate diameters from about 0.1 to 0.5 foot. The experiments were conducted in a flume 2 feet wide by 60 feet long and for most runs, depth was held...

The laboratory investigation of roughness in alluvial channels has led to the development of a special electronic device capable of mapping the streambed configuration under dynamic conditions. This electronic device employs an ultrasonic pulse-echo principle, similar to that of a fathometer, that utilizes microsecond techniques to give high accuracy in...

Normal faults offset a bedrock surface scoured by Pleistocene ice in several areas within and south of Yellowstone National Park. Recurrent earthquake shocks and fresh appearance of some scarps suggest that movement is continuing along some faults. Four systems of faults are described. Quaternary movement occurred along more than 60 faults on the Mirror Plateau, 15...

The Elk Ridge area of southeastern Utah contains uranium ore deposits in two lower members of the Chinle formation of Late Triassic age. Each member is mineralized in different parts of the area, and where both are present only the lower contains ore. Across the Elk Ridge area from southwest to northeast, successively younger beds...

Populations of brook trout in streams of Shenandoah National Park were reduced drastically early in the past decade by a succession of unusually severe droughts and floods. The drying of stream beds, predation, and scouring were principal factors in the loss of fish. The park was closed to fishing in...

In 1951 and 1952, the U.S. Geological Survey conducted a program of uranium investigations and geologic mapping in the Monument Valley area, Apache and Navajo Counties, Ariz. About 700 square miles were mapped on the Navajo Indian Reservation. A resource appraisal of the area was an inherent part of the...

Channel pattern is used to describe the plan view of a reach of river as seen from an airplane, and includes meandering, braiding, or relatively straight channels.Natural channels characteristically exhibit alternating pools or deep reaches and riffles or shallow reaches, regardless of the type of pattern. The length of the...

Geologic conditions at Sheep Creek, Carlson Creek, and Turner Lake are discussed in relation to possible plans for hydroeletric power development. The proposed sites are on the rugged mainland of Southeastern Alaska along Gastineau Channel and Taku Inlet near Juneau. Bedrock in the area consists of a coastal strip of...

Among the rivers studied by us two broad types may be distinguished. Channels in the semi-arid areas scour at high discharges so that the bed lowers nearly as much as the water surface rises. Detailed data on the middle reaches of the Rio Grande in New Mexico during the spring...

The Jomac mine is in the White Canyon area. San Juan County, Utah, about 13 miles northeast of the town of White Canyon, Utah. The mine is owned by the Ellihill Mining Company, White Canyon, Utah. Mine workings consist pf two adits connected by a crosscut. Two hundred feet of...

During the summers of 1951 and 1952 the U.S. Geological Survey mapped the geology and uranium deposits in three 15-minute quadrangles on the Navajo Indian Reservation in Apache and Navajo Counties, northeastern Arizona. Exposed sedimentary rocks range in age from the Halgaito tongue of the Cutler formation (Permian) to the Salt Wash...

Most of the caraotite deposits in the Uravan and Gateway mining districts ate in the persistent upper sandstone stratum of the Salt Wash sandstone member of the Morrison formation, Areas In which this stratum is predominantly lenticular have been delimited from areas in which this stratum is predominantly nonlenticularar. Ground...

The area under study lies about ten miles east of Juneau, Alaska, and includes the bedded rocks adjacent to the Coast Range batholith, and intrusive rocks related to the batholith. Deep glaciated valleys and glacially scoured rocks are the major topographic features. The relief is about 3,500 feet, and the highest...