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A. D. Duerr

Publications and source records attributed to A. D. Duerr.

At least 19 recordsLinked to original sources
USGS1995

Exploring storm surge

This video provides a thorough discussion of storm surge, one of the most dangerous elements of hurricanes and major storms. This video illustrates basic storm surge principles, shows actual footage of storm surge damage and relates high-water level data collection by the U.S. Geological Survey to the task of recreating the storm surge event.

Open-File Report↗
USGS1995

Types of secondary porosity of carbonate rocks in injection and test wells in southern peninsular Florida

The types of secondary porosity present in carbonate injection intervals and in the overlying carbonate rocks were determined at 11 injection well sites and 3 test well sites in southern peninsular Florida. The hydrogeologic system consists of a thick sequence of carbonate rocks overlain by clastic deposits. Principal hydrogeologic units are the surficial aquifer system, the intermediate aquifer system or the intermediate confining unit,the Floridan aquifer system, and the sub-Floridan confining unit.The concept of apparent secondary porosity was used in this study because the secondary porosity features observed in a borehole television survey could have been caused by geologic processes as well as by drilling activities. The secondary porosity features identified in a television survey were evaluated using driller's comments and caliper, flowmeter, and temperature logs. Borehole intervals that produced or received detectable amounts of flow, as shown by flowmeter and temperature logs, provided evidence that the secondary porosity of the interval was spatially distributed and interconnected beyond the immediate vicinity of a borehole and, thus, was related to geologic processes. Features associated with interconnected secondary porosity were identified as effective secondary porosity. Fracture porosity was identified as the most common type of effective secondary porosity and was observed predominantly in dolomite and dolomitic limestone. Cavity porosity was the least common type of effective secondary porosity at the study sites. In fact, of the more than 17,500 feet of borehole studied a total of only three cavities constituting effective secondary porosity were identified at only two sites. These cavities were detected in dolomite rocks. Most apparent cavities were caused by drilling-induced collapse of naturally fractured borehole walls. Also, fractures usually were observed above and below cavities. The majority of vugs observed in the television surveys did not constitute effective secondary porosity. No effective secondary porosity was evident in the limestone or dolomitic limestone in the 300-foot interval immediately above the injection interval at six sites on the southeastern coast of Florida. Injection wells commonly are cased through the 300-foot interval. Fractures or cavities that contribute to effective secondary porosity may be present in this interval, but were not detectable with the methods used. Widely dispersed, inter- connected fractures or cavities can be present beyond the rock column intersected by the borehole and can provide local pathways for vertical migration of injected wastewater or the displaced saltwater. In the interval between the top of the Floridan aquifer system and a point 300 feet above the top of the injection interval, fractured rocks having effective secondary porosity were observed at five of six sites along the southeastern coast. Borehole characteristics usually are related to the drilling characteristics of the rock type. In limestone, borehole diameters are consistently larger than the bit diameter whereas in dolomite, borehole diameters are intermittently larger than the bit diameter. The large borehole diameters associated with dredging probably are caused by the presence of intensively fractured dolomite which collapses during drilling.

Water-Resources Investigations Report↗
USGS1988

Geohydrology and 1985 water withdrawals of the aquifer systems in southwest Florida, with emphasis on the intermediate aquifer system

In southwest Florida, principal hydrogeologic units include the surficial aquifer system, the intermediate aquifer system, and the Floridan aquifer system. The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by a middle confining unit. The intermediate aquifer system includes all water-bearing units and confining units between the overlying surficial aquifer system and the underlying Floridan aquifer system. Thickness of the surficial aquifer system ranges from 25 to 250 ft and thickness of the intermediate aquifer system ranges from less than 100 to more than 800 ft. Transmissivity of the intermediate aquifer system ranges from less than 200 to about 12,000 sq ft/day. In the northern part of the study area, the potentiometric surface of the intermediate aquifer system is higher than the potentiometric surface of the underlying Upper Floridan aquifer. Water is transmitted downward through the confining unit and recharges the Upper Floridan aquifer. The gradient in head reverses in the southern part of the study area. In 1985, an estimated 808 million gal/day of freshwater was withdrawn from all aquifers in the study area for irrigation, public and rural supply, and industrial use. Of this total, an estimated 68.9 million gal/day was withdrawn from the intermediate aquifer system. (USGS)

Water-Resources Investigations Report↗
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

Estimated water use in Southwest Florida, 1981, and summary of annual water use, 1970, 1975, and 1977-81

Water-use data for 1981 are summarized for 16 counties in the Southwest Florida Water Management District. Data include total use of groundwater and surface water for each of five water-use categories. The 1981 withdrawals for each category were as follows: 318 million gallons per day for public supply, 64 million gallons per day for rural, 314 million gallons per day for industrial, 595 million gallons per day for irrigation, and 7,680 million gallons per day for thermoelectric power generation of which 6,050 million gallons per day was saline water. (USGS)

Open-File Report↗
USGS1982

The Benchmark Farm Program: A method for estimating irrigation water use in southwest Florida

Irrigation water-use data are summarized in this report for 74 farms in the Southwest Florida Water Management District. Most data are for 1978-90, but 18 farms have data extending back to the early 1970's. Data include site number and location, season and year, crop type, irrigation system, monitoring method, and inches of water applied per acre. Crop types include citrus, cucumbers, pasture, peanuts, sod, strawberries, and tropical fish farms are also included. Water-application rates per growing season ranged from 0 inches per acre for several citrus and pasture sites to 239.7 inches per acre for a nursery site. The report also includes rainfall data for 12 stations throughout the study area. (USGS)

Florida↗