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R. M. Wolansky

Publications and source records attributed to R. M. Wolansky.

15 recordsLinked to original sources
USGS1986

Hydrogeology of the surficial and intermediate aquifers of central Sarasota County, Florida

The geohydrologic units underlying a 300 sq mi area in central Sarasota County, Florida, consist of the surficial aquifer, intermediate aquifers (Tamiami-upper Hawthorn and lower Hawthorn-upper Tampa aquifers) and confining units, the Floridan aquifer system, and the sub-Floridan confining unit. The saturated thickness of the surficial aquifer ranges from about 40 to 75 ft and the water table is generally within 5 ft of land surface. The Tamiami-upper Hawthorn is the uppermost intermediate aquifer. The top of the aquifer ranges from about 50 ft to about 75 below sea level and has an average thickness of about 100 ft. The lower Hawthorne-upper Tampa aquifer is the lowermost intermediate aquifer. The top of the aquifer ranges from about 190 to about 220 ft below sea level and its thickness ranges from about 200 to 250 ft. The quality of water in the surficial and the two intermediate aquifers is acceptable for potable use except near the coast. Water from the Floridan aquifer system is used primarily for agricultural purposes because it is too mineralized for most other uses; therefore, the surficial and intermediate aquifers are developed for water supply. The artesian pressure of the various aquifers generally increases with depth. A more detailed geohydrologic description is presented for the Ringling-MacArthur Reserve, a 51 sq mi area in the central part of the county that may be used by Sarasota County as a future water supply. Average annual rainfall is 56 inches and evapotranspiration is about 42 in at the Reserve. The area has a high water table, many sloughs and swamps, and undeveloped land, making it an attractive site as a potential source of water.

Florida↗
USGS1983

Hydrogeology of the Sarasota-Port Charlotte area, Florida

The surficial and intermediate aquifers are the major source of public water supplies in the Sarasota-Port Charlotte, Florida, area because of the relatively poor quality of Floridan aquifer water. The hydrogeologic framework consists of the surficial aquifer, intermediate aquifers (Tamiami-upper Hawthorn and lower Hawthorn-upper Tampa aquifers) and confining beds, Floridan aquifer, and lower confining bed (or base of the Floridan aquifer). The quality of ground water in the surficial and intermediate aquifers is generally good, except in the western (coastal) and southern parts where saltwater intrusion or incomplete flushing of connate water has occurred. The mineral content of ground water generally increases with depth and areally from the northeast towards the west and south. A water budget for the study area shows that an average annual rainfall of 51.0 inches minus an evapotranspiration of 38.0 inches per year and streamflow of 12.5 inches per year leaves 0.5 inch per year of recharge to the surficial aquifer. Combined pumpage from the aquifers is 1.06 inches per year. A preliminary quasi-time dimensional model has been applied to the study area to check the reasonableness of the hydrogeologic framework defined and of aquifer parameters. The model was considered calibrated when the final head matrix was within plus or minus 5 feet of the starting head.

Florida↗
USGS1983

Continuous seismic-reflection survey defining shallow sedimentary layers in the Charlotte Harbor and Venice areas, southwest Florida

A continuous marine seismic-reflection survey system was used to define the configuration of shallow sedimentary layers underlying the Charlotte Harbor and Venice areas, southwest Florida. Seismic profiling was conducted over a distance of about 57 miles of Charlotte Harbor, the Peace and Myakka Rivers, and the Intracoastal Waterway near Venice using a high resolution energy source capable of penetrating 200 feet of sediments with a resolution of 1 to 3 feet. Five stratigraphic units defined from the seismic records includes sediments to Holocene to early Miocene age. All seismic-profile records are presented, along with geologic sections constructed from the records. Seismic reflection amplitude, frequency, continuity, configuration, external form, and areal association were utilized to interpret facies and depositional environments of the stratigraphic units. The despositional framework of the units ranges from shallow shelf to prograded slope. The stratigraphic units are correlated with the surficial aquifer and intermediate artesian aquifers, and permeable zones of the aquifers are related to the seismic records. (USGS)

Florida↗
USGS1981

Generalized thickness of the Floridan aquifer, Southwest Florida Water Management District

This map report presents the thickness of the Floridan aquifer in the Southwest Florida Water Management District. The Floridan aquifer ranges in thickness from 600 feet in the northern part of the District to 2,400 feet in the southern part. It is composed chiefly of limestone and dolomite beds that range in age from early Miocene to middle Eocene. For this investigation, the formations considered to be part of the Floridan aquifer are: Lake City and Avon Park Limestones of middle Eocene age; Ocala Limestone of late Eocene age; Suwannee Limestone of Oligocene age; and permeable parts of the Tampa Limestone and Hawthorn Formation of Miocene age that are in hydrologic contact with the rest of the aquifer.

Florida↗
USGS1980

Configuration of the top of the highly permeable dolomite zone of the Floridan Aquifer, Southwest Florida Water Management District

This map report presents the configuration of the top of the highly permeable dolomite zone of the Floridan aquifer in the Southwest Florida Water Management District. The top of the highly permeable dolomite generally corresponds to the top of a thick bed of massive, hard, dark brown dolomite occurring in the Avon Park Limestone of Eocene age. The altitude of the top of the permeable dolomite varies from about 100 feet below the National Geodetic Vertical Datum of 1929 in the north to about 1 ,600 feet below the datum in the south. (Kosco-USGS)

Open-File Report↗
USGS1979

Generalized thickness of the surficial deposits above the confining bed overlying the Floridan Aquifer, Southwest Florida Water Management District

This map report presents the thickness of the surficial deposits overlying the upper confining bed of the Floridan aquifer in the Southwest Florida Water Management District. The surficial deposits range in thickness from less than 25 feet in the western part of the district to greater than 250 feet in the eastern part. The surficial deposits include sand, clayey sand, shell, and shelly marl that occur in the Holocene sand, Pleistocene marine terrace sand, and unconsolidated parts of the Fort Thompson Formation, Caloosahatchee Marl, Alachua Formation, and Bone Valley Formation. Lithologic logs and information from quarries were used in conjunction with an unpublished map prepared during an earlier investigation to compile this map at 1:250,000 scale. (Kosco-USGS)

Florida↗
USGS1979

Generalized thickness of the confining bed overlying the Floridan Aquifer, Southwest Florida Water Management District

This map presents the thickness of the confining bed overlying the Floridan aquifer in the Southwest Florida Water Management District and adjacent areas. The bed separates the surficial aquifer from the underlying Floridan aquifer. Lithologic logs and information from quarries were used in conjunction with an unpublished map to compile this map at 1:250,000 scale. Units included in the confining bed are: clay, sandy clay and marl, undifferentiated with respect to age, the Hawthorn Formation, and the unconsolidated sections of the Tampa Limestone. (Kosco-USGS)

Open-File Report↗
USGS1979

Potentiometric surface of Floridan Aquifer, southwest Florida Water Management District and adjacent areas, May 1979

A May 1979 potentiometric-surface map depicts the annual low water-level period. Potentiometric levels declined 4 to 21 feet between September 1978 and May 1979, in the citrus and farming sections of southern Hillsborough, northern Hardee, southwestern Polk, northwestern DeSoto, and Manatee Counties. Water levels in these areas are widely affected by pumping for irrigation and have the greatest range in fluctuations. Water-level declines ranged from 0 to 6 feet in coastal, northern, and southern areas of the Water Management District. Generally potentiometric levels were higher than previous May levels due to heavy rains in April and May. In parts of Hillsborough, Pasco, and Pinellas Counties, May 1979 potentiometric levels were 18 feet higher than those of September 1978.

Florida↗
USGS1979

Water table in the surficial aquifer and potentiometric surface of the Floridan Aquifer in selected well fields, west-central Florida, May 1979

The water table is the surficial aquifer and the potentiometric surface of the Floridan aquifer in a 1,200-square-mile area in west-central Florida are mapped semiannually by the U.S. Geological Survey. Maps are prepared showing water levels measured in wells each May to coincide with seasonal low levels, and each September to coincide with seasonal high levels. The mapped area shows 16 well fields which supplied 128 million gallons to municipalities on May 15, 1979. The water is withdrawn from the Floridan aquifer, the major aquifer in Florida. Water levels were significantly higher in May 1979 than in May 1978. Heavy rains on May 7 and 8th deluged the well-field areas with 2 to 18 inches of rain. The maximum increase in water levels from May 1978 to May 1979 was more than 8 feet at the Eldridge-Wilde well field. (USGS)

Open-File Report↗
USGS1979

Generalized configuration of the bottom of the Floridan aquifer, Southwest Florida Water Management District

This map presents the configuration of the bottom of the Floridan aquifer in the Southwest Florida Water Management District. The bottom of the aquifer generally corresponds to the beginning of consistent intergranular evaporites occurring in either the Avon Park, Lake City, or Oldsmar Limestones of Eocene age. The altitude of the bottom of the aquifer varies from about 600 feet below the National Geodetic Vertical Datum of 1929 in the north to about 3,000 feet below the datum in the South. (Kosco-USGS)

Florida↗
USGS1978

Potentiometric surface of the Floridan Aquifer, Southwest Florida Water Management District and adjacent areas, September 1978

A September 1978 potentiometric-surface map depicts the annual high water-level period of the Floridan aquifer in the Southwest Florida Management District. Potentiometric levels increased 10 to 25 feet between May 1978 and September 1978, in the citrus and farming sections of southern Hillsborough, northern Hardee, southwestern Polk and Manatee Counties. These areas are widely affected by pumping for irrigation and have the greatest fluctuations in water-levels between the low and high water-level periods. Water-level rises in coastal, northern and southern areas of the Water Management District ranged from 0 to 10 feet. (Woodard-USGS)

Open-File Report↗
USGS1978

Feasibility of water-supply development from the unconfined aquifer in Charlotte County, Florida

The unconfined aquifer in Charlotte County contains some potable water over most of the county, and represents a potential source of water supply to help satisfy the increasing demands of development. An estimated 150 billion cubic feet of relatively good quality water is stored in the unconfined aquifer. Transmissivity of this aquifer averages about 500 square feet per day, ranging from 100 to 7000 feet per day. Although recharge is primarily from rainfall, a significant amount occurs by upward movement of water from underlying confined aquifers through abandoned and flowing irrigation wells. Average annual recharge is estimated at 12 inches per year, and ranges from less than one inch to 16 inches per year. Chemical quality of the water is variable. However, chloride concentrations of water from the unconfined aquifer generally are less than 50 milligrams per liter. The area of greatest potential yield is located east of Telegraph Swamp in eastern Charlotte County. (Woodard-USGS)

Water-Resources Investigations Report↗