Publications
The following list of California Water Science Center publications includes both official USGS publications and journal articles authored by our scientists.
Filter Total Items: 1734
Use of a groundwater flow model to assess the location, extent, and hydrologic properties of faults in the Rialto-Colton Basin, California
Faults within a groundwater basin can greatly influence the direction of groundwater flow and contaminant migration. Existing steady-state and transient groundwater flow models were used to assess the location, extent, and hydrologic properties of two alternative fault configurations within the Rialto-Colton basin. Adjustments were made to the hydrologic properties of the faults and the location o
Authors
Linda R. Woolfenden
Subsidence reversal in a re-establish wetland in the Sacramento-San Joaquin Delta, California, USA
The stability of levees in the Sacramento-San Joaquin Delta is threatened by continued subsidence of Delta peat islands. Up to 6 meters of land-surface elevation has been lost in the 150 years since Delta marshes were leveed and drained, primarily from oxidation of peat soils. Flooding subsided peat islands halts peat oxidation by creating anoxic soils, but net accumulation of new material in rest
Authors
Robin L. Miller, Miranda S. Fram, Roger Fujii, Gail A. Wheeler
Integration of regional hydrologic modeling using FORTRAN and ArcGIS
No abstract available.
Authors
Alan L. Flint, Lorraine E. Flint
Influences of the unsaturated, saturated, and riparian zones on the transport of nitrate near the Merced River, California, USA
Transport and transformation of nitrate was evaluated along a 1-km groundwater transect from an almond orchard to the Merced River, California, USA, within an irrigated agricultural setting. As indicated by measurements of pore-water nitrate and modeling using the root zone water quality model, about 63% of the applied nitrogen was transported through a 6.5-m unsaturated zone. Transport times from
Authors
Joseph L. Domagalski, S.P. Phillips, E.R. Bayless, C. Zamora, C. Kendall, R.A. Wildman, J. G. Hering
Influence of plankton mercury dynamics and trophic pathways on mercury concentrations of top predator fish of a mining-impacted reservoir
Physical and biogeochemical characteristics of the aquatic environment that affect growth dynamics of phytoplankton and the zooplankton communities that depend on them may also affect uptake of methylmercury (MeHg) into the pelagic food web of oligotrophic reservoirs. We evaluated changes in the quality and quantity of suspended particulate material, zooplankton taxonomy, and MeHg concentrations c
Authors
A.R. Stewart, M. K. Saiki, J.S. Kuwabara, Charles N. Alpers, M. Marvin-DiPasquale, D. P. Krabbenhoft
Ecosystem conceptual model- Mercury
Mercury has been identified as an important contaminant in the Delta, based on elevated concentrations of methylmercury (a toxic, organic form that readily bioaccumulates) in fish and wildlife. There are health risks associated with human exposure to methylmercury by consumption of sport fish, particularly top predators such as bass species. Original mercury sources were upstream tributaries where
Authors
Charles N. Alpers, Collin A. Eagles-Smith, Chris Foe, Susan Klasing, Mark C. Marvin-DiPasquale, Darell Slotton, Lisamarie Windham-Myers
Application of MODFLOW’s farm process to California’s Central Valley
Historically, California’s Central Valley has been one of the most productive agricultural regions in the world. The Central Valley also is rapidly becoming an important area for California’s expanding urban population. During 1980–2007, the population nearly doubled in the Central Valley, increasing the competition for water. Because of the importance of ground water in the Central Valley, the U.
Authors
Claudia C. Faunt, Randall T. Hanson, Wolfgang Schmid, Kenneth Belitz
Development of a model to assess ground-water availability in California's Central Valley
No abstract available.
Authors
Claudia C. Faunt, Randall T. Hanson, Kenneth Belitz
Evidence for crustal degassing of CF4 and SF6 in Mojave Desert groundwaters
Dissolved tetrafluoromethane (CF4) and sulfur hexafluoride (SF6) concentrations were measured in groundwater samples from the Eastern Morongo Basin (EMB) and Mojave River Basin (MRB) located in the southern Mojave Desert, California. Both CF4 and SF6 are supersaturated with respect to equilibrium with the preindustrial atmosphere at the recharge temperatures and elevations of the Mojave Desert. Th
Authors
D.A. Deeds, M.K. Vollmer, J.T. Kulongoski, B.R. Miller, J. Muhle, C.M. Harth, J. A. Izbicki, David R. Hilton, R.F. Weiss
Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States
In 2003–2005, systematic studies in four contrasting hydrogeologic settings were undertaken to improve understanding of source and transport controls on nitrate movement to public supply wells (PSW) in principal aquifers of the United States. Chemical, isotopic, and age tracer data show that agricultural fertilizers and urban septic leachate were the primary sources of large nitrate concentrations
Authors
P. B. McMahon, J.K. Böhlke, L. J. Kauffman, K.L. Kipp, M.K. Landon, C. A. Crandall, K.R. Burow, C. J. Brown
Low-Level detections of halogenated volatile organic compounds in groundwater: Use in vulnerability assessments
Concentrations of halogenated volatile organic compounds (VOCs) were determined by gas chromatography (GC) with an electron-capture detector (GC-ECD) and by gas chromatography with mass spectrometry (GC-MS) in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used for drinking-water purposes or was from a monitoring well in an area nea
Authors
Niel Plummer, E. Busenberg, S. M. Eberts, L. M. Bexfield, C. J. Brown, L.S. Fahlquist, B. G. Katz, M.K. Landon
Near-surface location, geometry, and velocities of the Santa Monica Fault Zone, Los Angeles, California
High-resolution seismic-reflection and seismic-refraction imaging, combined with existing borehole, earthquake, and paleoseismic trenching data, suggest that the Santa Monica fault zone in Los Angeles consists of multiple strands from several kilometers depth to the near surface. We interpret our seismic data as showing two shallow-depth low-angle fault strands and multiple near-vertical (???85??)
Authors
R. D. Catchings, G. Gandhok, M. R. Goldman, D. Okaya, M. J. Rymer, G.W. Bawden