Publications

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

Semiquantitative determinations of the clay-mineral composition have been made on nearly synoptic samples of surface suspended sediments collected seasonally throughout the San Francisco Bay system. The relative amounts of chlorite + kaolinite are generally highest in the northern reach of the system, whereas illite is dominant in the southern reach. The proportion of montmorillonite is low throug

The magnitude and frequency of floods from gaged and ungaged drainage areas in California, for any recurrence interval from 2 to 100 years, can be estimated by use of the method presented. Equations relating flood magnitudes of selected frequency to basin characteristics such as drainage area, precipitation, and altitude were developed for six regions in the State. Nomographs are included for solu

Water distribution systems in Santa Clara County, Calif., may be damaged and rendered inoperable by a large earthquake or other disaster. In such an event, individual agencies may have to implement emergency measures to supply water for drinking, firefighting, decontamination, or other purposes. In Santa Clara County, 128 wells have been identified as potential water-supply sources in emergencies.

The water-bearing potential of the geologic formations in the western part of Santa Cruz County, Calif., is evaluated. Most of the sedimentary formations in this area are fine-grained rocks of Tertiary age that have been folded and faulted. These rocks, in general, yield supplies of water sufficient only for individual domestic supplies. The Lompico and Santa Margarita Sandstones, however, are coa

Thermal springs and wells in Long Valley, California, issue sodium bicarbonate‐chloride waters containing 1000–1420 mg/l of dissolved solids. Thermal waters of sodium bicarbonate‐chloride composition are usually associated with hot‐water reservoirs. Chloride concentrations and stable isotope data indicate that the thermal waters have had varied histories. All of the thermal springs issue a mixture

No abstract available. 

No abstract available.

Well waters along two traverse lines were sampled in 1963 and tested for tritium concentration. Haskell et al. [1966] estimated from the apparent thermonuclear tritium concentrations that groundwater had moved westward in the lower water‐bearing zone at a maximum velocity of 14–16.5 mi (23–27 km) in 9 yr. The maximum velocities and permeabilities estimated from the 1963 sampling were about an orde