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George Ozuna

Senior Science Advisor for Oklahoma-Texas Water Science Center

Science and Products

Geohydrologic Framework of the Edwards and Trinity Aquifers, South-Central Texas

This five-year USGS project, funded by the National Cooperative Geologic Mapping Program, is using multidisciplinary approaches to reveal the surface and subsurface geologic architecture of two important Texas aquifers: (1) the Edwards aquifer that extends from south of Austin to west of San Antonio and (2) the southern part of the Trinity aquifer in the Texas Hill Country west and south of Austin
Authors
Charles D. Blome, Jason R. Faith, George B. Ozuna
By
Geosciences and Environmental Change Science Center

Geologic framework and hydrogeologic characteristics of the Edwards Aquifer recharge zone, Bexar County, Texas

In Bexar County, residential and commercial development on the Edwards aquifer recharge zone is increasing. The aquifer possibly can be contaminated by spills, leakage of hazardous materials, or runoff from the rapidly developing urban areas that surround, or are built on, the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone. Furthermore, some of the
Authors
W.G. Stein, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Determination of nanogram per liter concentrations of volatile organic compounds in water by capillary gas chromatography and selected ion monitoring mass spectrometry and its use to define groundwater flow directions in Edwards Aquifer, Texas

A method has been developed to measure nanogram per liter amounts of selected volatile organic compounds (VOCs) including dichlorodifluoromethane, trichlorofluoromethane, cis-1,2-dichloroethene, trichloroethene, tetrachloroethene, and the isomers of dichlorobenzene in water. The method uses purge-and-trap techniques on a 100 mL sample, gas chromatography with a megabore capillary column, and elect
Authors
P.M. Buszka, D.L. Rose, G. B. Ozuna, G.E. Groschen
By
Water Resources Mission Area, National Water Quality Laboratory

Ground-water conditions in Pecos County, Texas, 1987

A comparison of 1987 water levels with historical (1940-49) water levels in the Edwards-Trinity (Plateau) aquifer indicated that water levels declined more than 50 feet in three locations in the Leon-Belding irrigation area, in an area north of Fort Stockton, and in a well east of Bakersfield. Maximum measured declines were 54 and 82 feet in the Leon-Belding irrigation area. The maximum measured r
Authors
T. A. Small, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Reconnaissance investigation of the geology and hydrogeology of Lackland Air Force Base, San Antonio, Texas

An investigation at Lackland Air Force Base and Lackland Air Force Base Training Annex (Medina Base) was conducted from May to September 1988 to delineate the subsurface geology, to describe the hydrogeology within the study area, and to determine possible migration pathways for contaminants. Data from this investigation supplement data collected in conjunction with other Air Training Command stud
Authors
G. B. Ozuna, T. A. Small
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards aquifer, San Antonio area, Texas, 1986, with 1934-86 summary

No abstract available.
Authors
G. B. Ozuna, G.M. Nalley, W.G. Stein
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards aquifer, San Antonio area, Texas, 1985, with 1934-85 summary

No abstract available.
Authors
G. B. Ozuna, G.M. Nalley, M. N. Bowman
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1983-84, with 1934-84 summary

No abstract available.
Authors
R.D. Reeves, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1982, with 1934-82 summary

No abstract available.
Authors
R.D. Reeves, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1981, with 1934-81 summary

The average annual ground-water recharge to the Edwards aquifer in the San Antonio area, Texas, from 1934 through 1981, was 612,400 acre-feet. The recharge in 1981 was 1,448,400 acre-feet, which is the third highest annual recharge since 1934. A maximum annual recharge of 1,711,200 acre-feet occurred in 1958, and a minimum annual recharge of 43,700 acre-feet occurred in 1956. The calculated annual
Authors
R.D. Reeves, R. W. Maclay, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center
link
Pecos River below Barstow Dam, Texas

Stream Science Capabilties

Texas has 16 river basins and more than 15 major rivers and more than 100 secondary streams. These rivers and streams play a vital role for communities and ecosystems across Texas by providing water for drinking, recreation, and irrigation; recharging aquifers; and transporting sediment and nutrients.The USGS Texas Water Science Center (TXWSC) collects data and has science projects at several all...
By
Oklahoma-Texas Water Science Center
link

Stream Science Capabilties

Texas has 16 river basins and more than 15 major rivers and more than 100 secondary streams. These rivers and streams play a vital role for communities and ecosystems across Texas by providing water for drinking, recreation, and irrigation; recharging aquifers; and transporting sediment and nutrients.The USGS Texas Water Science Center (TXWSC) collects data and has science projects at several all...
Learn More

Science and Products

Geohydrologic Framework of the Edwards and Trinity Aquifers, South-Central Texas

This five-year USGS project, funded by the National Cooperative Geologic Mapping Program, is using multidisciplinary approaches to reveal the surface and subsurface geologic architecture of two important Texas aquifers: (1) the Edwards aquifer that extends from south of Austin to west of San Antonio and (2) the southern part of the Trinity aquifer in the Texas Hill Country west and south of Austin
Authors
Charles D. Blome, Jason R. Faith, George B. Ozuna
By
Geosciences and Environmental Change Science Center

Geologic framework and hydrogeologic characteristics of the Edwards Aquifer recharge zone, Bexar County, Texas

In Bexar County, residential and commercial development on the Edwards aquifer recharge zone is increasing. The aquifer possibly can be contaminated by spills, leakage of hazardous materials, or runoff from the rapidly developing urban areas that surround, or are built on, the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone. Furthermore, some of the
Authors
W.G. Stein, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Determination of nanogram per liter concentrations of volatile organic compounds in water by capillary gas chromatography and selected ion monitoring mass spectrometry and its use to define groundwater flow directions in Edwards Aquifer, Texas

A method has been developed to measure nanogram per liter amounts of selected volatile organic compounds (VOCs) including dichlorodifluoromethane, trichlorofluoromethane, cis-1,2-dichloroethene, trichloroethene, tetrachloroethene, and the isomers of dichlorobenzene in water. The method uses purge-and-trap techniques on a 100 mL sample, gas chromatography with a megabore capillary column, and elect
Authors
P.M. Buszka, D.L. Rose, G. B. Ozuna, G.E. Groschen
By
Water Resources Mission Area, National Water Quality Laboratory

Ground-water conditions in Pecos County, Texas, 1987

A comparison of 1987 water levels with historical (1940-49) water levels in the Edwards-Trinity (Plateau) aquifer indicated that water levels declined more than 50 feet in three locations in the Leon-Belding irrigation area, in an area north of Fort Stockton, and in a well east of Bakersfield. Maximum measured declines were 54 and 82 feet in the Leon-Belding irrigation area. The maximum measured r
Authors
T. A. Small, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Reconnaissance investigation of the geology and hydrogeology of Lackland Air Force Base, San Antonio, Texas

An investigation at Lackland Air Force Base and Lackland Air Force Base Training Annex (Medina Base) was conducted from May to September 1988 to delineate the subsurface geology, to describe the hydrogeology within the study area, and to determine possible migration pathways for contaminants. Data from this investigation supplement data collected in conjunction with other Air Training Command stud
Authors
G. B. Ozuna, T. A. Small
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards aquifer, San Antonio area, Texas, 1986, with 1934-86 summary

No abstract available.
Authors
G. B. Ozuna, G.M. Nalley, W.G. Stein
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards aquifer, San Antonio area, Texas, 1985, with 1934-85 summary

No abstract available.
Authors
G. B. Ozuna, G.M. Nalley, M. N. Bowman
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1983-84, with 1934-84 summary

No abstract available.
Authors
R.D. Reeves, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1982, with 1934-82 summary

No abstract available.
Authors
R.D. Reeves, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center

Compilation of hydrologic data for the Edwards Aquifer, San Antonio area, Texas, 1981, with 1934-81 summary

The average annual ground-water recharge to the Edwards aquifer in the San Antonio area, Texas, from 1934 through 1981, was 612,400 acre-feet. The recharge in 1981 was 1,448,400 acre-feet, which is the third highest annual recharge since 1934. A maximum annual recharge of 1,711,200 acre-feet occurred in 1958, and a minimum annual recharge of 43,700 acre-feet occurred in 1956. The calculated annual
Authors
R.D. Reeves, R. W. Maclay, G. B. Ozuna
By
Water Resources Mission Area, Oklahoma-Texas Water Science Center
link
Pecos River below Barstow Dam, Texas

Stream Science Capabilties

Texas has 16 river basins and more than 15 major rivers and more than 100 secondary streams. These rivers and streams play a vital role for communities and ecosystems across Texas by providing water for drinking, recreation, and irrigation; recharging aquifers; and transporting sediment and nutrients.The USGS Texas Water Science Center (TXWSC) collects data and has science projects at several all...
By
Oklahoma-Texas Water Science Center
link

Stream Science Capabilties

Texas has 16 river basins and more than 15 major rivers and more than 100 secondary streams. These rivers and streams play a vital role for communities and ecosystems across Texas by providing water for drinking, recreation, and irrigation; recharging aquifers; and transporting sediment and nutrients.The USGS Texas Water Science Center (TXWSC) collects data and has science projects at several all...
Learn More