Publications

Mesozoic granitoid rocks adjacent to the San Andreas fault in central California have retained their radiogenic Ar for the last 70 m.y. but have, generally, the highest 18O and H2O+ contents and the lowest D contents of all the granitoid rocks in California. The geographical coincidence of the D, 18O, and H2O+ patterns with the present trace of the San Andreas fault leave little doubt that some ki

Rivers draining nearly one third of California reach sea level in the Sacramento-San Joaquin delta. Though tapered toward a constricted outlet and separated from the sea by a chain of estuarine bays and straits, the delta resembles deltas built into open-marine environments in that (1) its principal landforms--tidal wetlands and natural levees--are typical features of such delta, and (2) the funda

A required 1,100 gallons of water per minute for irrigating agricultural lands used by the Coast Indian Community on the Resighini Rancheria near Klamath, Califomia, cannot be developed from wells. However, the required quantity of water might be developed from a trench installed in sand and gravel deposits that are hydraulically connected with the Klamath River.

Adequate supplies of ground water for municipal use generally are not available within a 3-mile radius of Pescadero, San Mateo County, California. The required quantity of 100 gallons per minute probably could be obtained from one or more wells in the alluvium along Pescadero Creek; however, the quality of the water probably would deteriorate with time and might not be suitable for public supply f

Nitrogen in the unsaturated soil zone in the Highland-East Highlands area of San Bernardino County, Calif., has been suspected as the source of nitrate in water from wells. Plans to recharge the local aquifers with imported surface water would raise the water table and intercept that nitrogen. This study was made to describe the distribution of inorganic nitrogen and other chemical constituents an

No abstract available.

The chemical composition of rainfall at Menlo Park, on San Francisco Bay, is compared with rainfall at Petrolia, which is near the coast about 500 km north of San Francisco. Sequential samples representing 1.35 to 5.4 mm of rain were collected from November 1971 to January 1972. At rural Petrolia the Cl:Na ratio was that of seawater for Cl concentrations ranging from 0.02 to 38 mg/l. In metropolit

No abstract available.

The city of San Bernardino is in a semiarid inland valley about 60 miles (100 kilometers) east of Los Angeles. The southern part of the city is traversed by the San Jacinto fault. Adjacent to the upgradient (northeast) side of the fault is a 10 square mile (26 square kilometers) area which contains a zone in the alluvial ground‐water basin that formerly was under artesian pressure and consisted of

A two-dimensional (vertical) steady-state numerical model that simulates water circulation and dissolved-silica distributions is applied to northern San Francisco Bay. The model (1) describes the strong influence of river inflow on estuarine circulation and, in turn, on the biologically modulated silica concentration, and (2) shows how rates of silica uptake relate to silica supply and mixing rate

An evaluation was made of the potential for potable-water supplies at 13 sites in or near Redwood National Park, Calif. The National Park Service is planning the development of visitor facilities at these sites. At some sites, locations are given for test-well drilling or springs are recommended for development. Chemical analyses of water from selected surface-water supplies and from some wells an

Streamflow, sediment-discharge, and water-quality data are being collected in the Calabazas Creek basin, Santa Clara County, Calif., to determine annual water and sediment discharge at base-line conditions that are representative of a basin prior to urbanization. Results of the first 3 years of the study (1973-75) are given in this report. Climatic conditions during this period were representative