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J. V. Brahana

Publications and source records attributed to J. V. Brahana.

16 recordsLinked to original sources
USGS2007

Dry Stream Reaches in Carbonate Terranes: Surface Indicators of Ground-Water Reservoirs

In areas where dry stream reaches occur, subsurface drainage successfully competes with surface drainage, and sheet-like dissolution openings have developed parallel to bedding creating the ground-water reservoir. Union Hollow in south-central Tennessee is the setting for a case study that illustrates the application of the dry stream reach technique. In this technique, dry stream reach identification is based on two types of readily acquired information: remotely sensed black and white infrared aerial photography; and surface reconnaissance of stream channel characteristics. Test drilling in Union Hollow subsequent to identification of the dry reach proved that a localized ground-water reservoir was present.

Water Resources Bulletin↗
USGS2001

Hydrogeology and ground-water flow in the Memphis and Fort Pillow aquifers in the Memphis area, Tennessee

On the basis of known hydrogeology of the Memphis and Fort Pillow aquifers in the Memphis area, a three-layer, finite-difference numerical model was constructed and calibrated as the primary tool to refine understanding of flow in the aquifers. The model was calibrated and tested for accuracy in simulating measured heads for nine periods of transient flow from 1886-1985. Testing and sensitivity analyses indicated that the model accurately simulated observed heads areally as well as through time. The study indicates that the flow system is currently dominated by the distribution of pumping in relation to the distribution of areally variable confining units. Current withdrawal of about 200 million gallons per day has altered the prepumping flow paths, and effectively captured most of the water flowing through the aquifers. Ground-water flow is controlled by the altitude and location of sources of recharge and discharge, and by the hydraulic characteristics of the hydrogeologic units. Leakage between the Fort Pillow aquifer and Memphis aquifer, and between the Memphis aquifer and the water-table aquifers (alluvium and fluvial deposits) is a major component of the hydrologic budget. The study indicates that more than 50 percent of the water withdrawn from the Memphis aquifer in 1980 is derived from vertical leakage across confining units, and the leakage from the shallow aquifer (potential source of contamination) is not uniformly distributed. Simulated leakage was concentrated along the upper reaches of the Wolf and Loosahatchie Rivers, along the upper reaches of Nonconnah Creek, and the surficial aquifer of the Mississippi River alluvial plain. These simulations are supported by the geologic and geophysical evidence suggesting relatively thin or sandy confining units in these general locations. Because water from surficial aquifers is inferior in quality and more susceptible to contamination than water in the deeper aquifers, high rates of leakage to the Memphis aquifer may be cause for concern. A significant component of flow (12 percent) discharging from the Fort Pillow aquifer was calculated as upward leakage to the Memphis aquifer. This upward leakage was generally limited to areas near major pumping centers in the Memphis aquifer, where heads in the Memphis aquifer have been drawn significantly below heads in the Fort Pillow aquifer. Although the Fort Pillow aquifer is not capable of producing as much water as the Memphis aquifer for similar conditions, it is nonetheless a valuable resource throughout the area.

Water-Resources Investigations Report↗
USGS1990

36C1 measurements and the hydrology of an acid injection site

In an area in western Tennessee (United States), an industrial firm is injecting acidic (pH = 0.1) iron chloride into permeable zones of carbonate rocks at depths ranging from 1000 to 2200 m below land surface. Overlying the injection zone at a depth of approximately 500 m below land surface is a regional fresh-water aquifer, the Knox aquifer. A study is currently underway to investigate whether the injection wells are hydraulically isolated from the fresh-water aquifer. Drilling of a test well that will reach a total depth of 2700 m has been initiated. The 36Cl content of 15 samples from the Knox aquifer, from monitor wells in the vicinity of the injection site, and from the test well have been analyzed. ?? 1990.

Nuclear Instruments and Methods in Physics Researc↗
USGS1988

Hydrogeology and preliminary assessment of regional flow in the upper Cretaceous and adjacent aquifers in the northern Mississippi embayment

On a regional scale, the ground-water system of the northern Mississippi embayment is composed of a series of nonindurated elastic sediments that overlie a thick sequence of Paleozoic carbonates, sandstones, and shales. Precambrian crystalline rocks form both the structural and the hydrogeologic basement throughout the northern embayment. The units that comprise the hydrogeologic framework of this study are the alluvium-lower Wilcox aquifer, the Midway confining unit, the Upper Cretaceous aquifer, the Cretaceous-Paleozoic confining unit, and the Ozark-St. Francois aquifer. The Upper Cretaceous aquifer of Late Cretaceous age is the primary focus of this investigation; the study is part of the Gulf Coast Regional Aquifer-System Analysis. A ground-water flow model was developed as the main tool to refine the concepts of deep regional flow in the northern Mississippi embayment. This four layer finite-difference model enabled testing of alternative boundary concepts and provided a refined definition of the hydrologic budget of the deep aquifers. The alluvium-lower Wilcox aquifer, the Upper Cretaceous aquifer, and the Ozark-St.Francois aquifer form layers 2 through 4, respectively. Layer 1 is an inactive layer of constant heads representing shallow water levels, which are a major control on recharge to and discharge from the regional system. A matrix of leakance values simulates each confining unit, allowing vertical interchange of water between different aquifers. The model was calibrated to 1980 conditions by using the assumption that 1980 was near steady-state conditions; it was calibrated to simulate observed heads within acceptable limits. For this preliminary model, calculated heads were found to be most sensitive to pumping, and least sensitive to the leakance. By using all available water-quality and water-level data, alternative boundary conditions were tested by comparing model simulated heads to observed heads. Simulation indicated that the major discharge zone for the Upper Cretaceous aquifer occurred along a narrow area coincident with the boundary of a buried rift. The results of the early modeling effort also contribute to a better understanding of the regional hydrologic budget, indicating that upward leakage from the Ozark-St. Francois aquifer to the Upper Cretaceous aquifer is about 43 cubic feet per second, with about 30 cubic feet per second occuring west of the western margin of the embayment. Calculations suggest upward recharge of about 68 cubic feet per second occurs to the lower Wilcox-alluvium aquifer from the Upper Cretaceous aquifer. Simulation results also indicate that the Midway is an effective regional confining unit.

northern Mississippi embayment↗
USGS1987

Quality of water from freshwater aquifers and principal well fields in the Memphis Area, Tennessee

Water from the freshwater aquifers in the Memphis area is suitable for most uses. Freshwater aquifers are the alluvium and fluvial (terrace) deposits of Quaternary age, the Memphis Sand and Fort Pillow Sand of Tertiary age, and the Ripley Formation and McNairy Sand of Cretaceous age. About 180 million gallons/day (mgd) of freshwater are withdrawn from the Memphis Sand, primarily for municipal and industrial use; the Memphis Sand is the principal aquifer supplying the City of Memphis. The alluvium provides water for irrigation and some industrial uses, and the fluvial deposits provide water for domestic use in rural areas. The Fort Pillow Sand supplies water for some municipal and industrial uses. The Ripley-McNairy aquifer is not used as a source of water. Water from the alluvium, fluvial deposits, and Memphis Sand is a calcium bicarbonate type, and water from the Fort Pillow Sand and Ripley-McNairy aquifer is a sodium bicarbonate type. Dissolved solids concentrations are low in the Memphis Sand, with a median value of 83 mg/L, and are high in the Ripley-McNairy aquifer with a value of about 1,000 mg/L. Water is very soft in the Fort Pillow Sand with a median hardness value of 9 mg/L as CaCO3 and is very hard in the alluvium with a median value of 285 mg/L. Iron concentrations are low in the fluvial deposits with a median value of 50 micrograms/L and are high in the alluvium with a median value of 5,200 micrograms/L. Temperature of the water generally increases with depth, ranging from 16.0 C in the alluvium and fluvial deposits to about 32.0 C in the Ripley-McNairy aquifer. Water from the Memphis Sand at Memphis Light, Gas and Water Division well fields has very low mineralization. Median values are 79 mg/L dissolved solids concentrations, 56 mg/L alkalinity as CaCO3, 46 mg/L hardness as CaCO3, 4 mg/L chloride, 3.5 mg/L sulfate, and 600 micrograms/L iron.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee: Cumberland Plateau aquifer system

The Cumberland Plateau aquifer system consists of Pennsylvanian sandstones, conglomerates, shales, and coals which underlie the Cumberland Plateau in Tennessee. Major water-bearing zones occur within the sandstones and conglomerates in interconnected fractures. The water-bearing formations are separated by shale and siltstone that retard the vertical circulation of ground water. The Pennington Formation serves as the base of this aquifer system and is an effective confining unit. The Cumberland Plateau aquifer system is an important water source for the Cumberland Plateau. Wells and springs from the aquifer system supply most of the rural domestic and public drinking-water supplies. Water from wells drilled into the Cumberland Plateau aquifer system is generally of good to excellent quality. Of the 32 water-quality analyses on file from this aquifer, only 2 had dissolved-solids concentrations greater than 500 milligrams per liter, and about three-fourths had less than 200 milligrams per liter dissolved solids. However, no samples from depths greater than 300 feet below land surface have been recorded. Ground water from locations where the sandstones are buried deeply, such as the Wartburg basin, may contain dissolved-solids concentrations greater than 1,000 milligrams per liter.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee – The central basin aquifer system

The Central Basin aquifer system is composed of Devonian and Ordovician carbonate and shale rocks. This aquifer occurs west of the Valley and Ridge province and crops out in the Central Basin and the Sequatchie Valley of Tennessee. Ground water in the Central Basin aquifer occurs primarily in solution openings and fractures, and the flow system is generally limited to 300 feet or less below land surface. However, some fracture and minor faults may allow vertical recharge to the underlying Knox Group, which marks the lower boundary of the Central Basin aquifer system. Away from the Central Basin, the upper limit of the Central Basin aquifer system is the Chattanooga Shale, an effective confining unit. The Central Basin aquifer system, an important source of drinking water, supplies most of the rural domestic and many public supplies of drinking water in the Central Basin and the Sequatchie Valley. Dissolved-solids concentrations often are less than 500 milligrams per liter where the aquifer is part of a dynamic flow system. Dissolved-solids concentrations may reach thousands or tens of thousands of milligrams per liter below the zone of dynamic flow.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee -- Highland Rim aquifer system

The Highland Rim aquifer system is primarily composed of Mississippian carbonates. This aquifer system occurs west of the Valley and Ridge province. It crops out in the Highland Rim and the Sequatchie Valley. It has been removed by erosion from the Central Basin. Ground water in the Highland Rim aquifer system occurs primarily in secondary openings. These openings include solution openings, joints, and faults. The Chattanooga Shale is the lower confining layer for the Highland Rim aquifer system. Under the Cumberland Plateau, this aquifer system is separated from the overlying Pennsylvanian formations by the Pennington Shale. The Highland Rim aquifer system is an important source of drinking water. It supplies most of the rural, domestic and many public supplies of drinking water in the Highland Rim. Where there is a dynamic flow system, dissolved-solids concentrations are less than 500 milligrams per liter. However, isolated cells may exist where the ground water has dissolved-solids concentrations of more than 1,000 milligrams per liter.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee: Basal sandstone west of the Valley and Ridge Province

The basal sandstone is a poorly sorted, well indurated sandstone, which lies below the Conasauga Group and above the Precambrian crystalline rocks. It is an unknown resource defined by limited data, with only 14 data points (wells) for the entire State of Tennessee. The basal sandstone is thought to occur throughout most of the State west of the Valley and Ridge province at depths of generally more than 5,500 feet below land surface. The basal sandstone probably does not receive significant vertical recharge because the sandstone is overlain by such a thick sequence of flat-lying, low-porosity lower Paleozoic carbonates and shales. Data from two sites indicate that the rocks of the basal sandstone have relatively low porosity and permeability. The concentrations of dissolved solids in water from the basal sandstone range from less than 40,000 milligrams per liter to more than 200,000 milligrams per liter. The basal sandstone is not being used as a source of drinking water because of its great depth, the presence of shallower sources of drinking water, and possible concentrations of more than 10,000 milligrams per liter dissolved solids throughout its area of occurrence.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee– Tertiary aquifer system

The Tertiary aquifer system in Tennessee is composed of sands and clays of Quaternary and Tertiary age. The aquifer system occurs in west Tennessee from the Mississippi River east to the outcrop of the Porters Creek Clay. Groundwater in the Tertiary aquifer system is recharged at outcrops and through overlying permeable deposits. The underlying Porters Creek Clay acts as the lower confining layer. The Tertiary aquifer system is the single most prolific source of groundwater in Tennessee. The water quality is excellent with generally less than 500 mg/L dissolved solids.

Tennessee↗
USGS1986

Preliminary delineation and description of the regional aquifers of Tennessee– The Cretaceous aquifer system of west-Tennessee

The Cretaceous aquifer system in western Tennessee is composed of sand, gravel, and clay. The aquifer system is under confined conditions except in the outcrop area. Ground water is recharged by precipitation on the outcrop area and through some overlying permeable deposits. The hydraulic gradient in the confined aquifers is about 1 foot per mile generally toward the west. The Cretaceous aquifer system unconformably overlies the consolidated Paleozoic formations and is overlain and confined by the Porters Creek Clay. The Cretaceous aquifer system is used as a source of water supply primarily in the outcrop area. West of the outcrop of this aquifer system, ground water can be obtained at shallower depths and with better water quality. The water of the Cretaceous aquifers generally have very good quality in the outcrop area. The dissolved solids increase down gradient to more than 1,000 milligrams per liter in parts of Shelby County. High iron concentrations are present in some areas.

Tennessee↗
USGS1985

Ground-water quality data from the northern Mississippi embayment: Arkansas, Missouri, Kentucky, Tennessee, and Mississippi

Forty-five analyses of ground-water quality from 42 selected wells in the McNairy-Nacatoch-Ripley and lower Wilcox aquifers of the northern Mississippi embayment have been compiled as part of the Gulf Coast Regional Aquifer System Analysis (RASA) project of the U.S. Geological Survey. Thirty-seven wells were sampled during the period October 1983 to September 1984 specifically for this RASA study; three of these wells were sampled twice. Five wells were sampled during the period January 1981 to March 1985 for other projects. All 45 analyses are included herein as a single data base that will be used for geochemical modeling of mineral saturation and mass transfer in the McNairy-Nacatoch-Ripley aquifer. The report contains two figures, six tables of data, and a brief documentation of the methods used for sample collection and analysis. The figures are maps showing locations of sampling sites for each of the two aquifers. The tables of data include (1) well descriptions and (2) concentrations of major constituents, trace constituents, dissolved gases, stable and unstable isotopes of low mass (C, H, 0, and S>, and unstable isotopes of high mass (Rn, Ra, and U).

Arkansas, Kentucky, Mississippi, Missouri, Tenness↗
USGS1985

Delineation and description of the regional aquifers of Tennessee — The Knox Aquifer in central and west Tennessee

The Knox aquifer is composed of the Cambrian and Ordovician age carbonate rocks of the Knox Group. This aquifer occurs throughout Tennessee, west of the Valley and Ridge province. The Knox crops out in the Sequatchie Valley and in the Wells Creeks cryptoexplosive structure on the Northwestern Highland Rim. Groundwater in the upper Knox occurs primarily in solution openings. The aquifer may be recharged through fractures and faults in the overlying Ordovician limestones in Middle Tennessee. The underlying Conasauga Shale acts as the lower confining layer. Throughout parts of the Central Basin province, the Knox aquifer is an important source of water for rural domestic supplies. In these areas, groundwater from the Knox generally has less than 1,000 milligrams/L dissolved solids. Away from the Central Basin, the dissolved solids concentrations increases. It may approach brine concentrations under the Cumberland Plateau.

Tennessee↗