Conduit enlargement in an eogenetic karst aquifer, , Moore Paul J. , Martin Jonathan B. , Screaton Elizabeth J. , Neuhoff Philip S.

Most concepts of conduit development have focused on telogenetic karst aquifers, where low matrix permeability focuses flow and dissolution along joints, fractures, and bedding planes. However, conduits also exist in eogenetic karst aquifers, despite high matrix permeability which accounts for a significant component of flow. This study investigates dissolution within a 6-km long conduit system in the eogenetic Upper Floridan aquifer of north-central Florida that begins with a continuous source of allogenic recharge at the Santa Fe River Sink and discharges from a first-magnitude spring at the Santa Fe River Rise. Three sources of water to the conduit include the allogenic recharge, diffuse recharge through epikarst, and mineralized water upwelling from depth. Results of sampling and inverse modeling using PHREEQC suggest that dissolution within the conduit is episodic, occurring only during 30% of 16 sampling times between March 2003 and April 2007. During low flow conditions, carbonate saturated water flows from the matrix to the conduit, restricting contact between undersaturated allogenic water with the conduit wall. When gradients reverse during high flow conditions, undersaturated allogenic recharge enters the matrix. During these limited periods, estimates of dissolution within the conduit suggest wall retreat averages about 4 × 10−6 m/day, in agreement with upper estimates of maximum wall retreat for telogenetic karst. Because dissolution is episodic, time-averaged dissolution rates in the sink-rise system results in a wall retreat rate of about 7 × 10−7 m/day, which is at the lower end of wall retreat for telogenetic karst. Because of the high permeability matrix, conduits in eogenetic karst thus enlarge not just at the walls of fractures or pre-existing conduits such as those in telogenetic karst, but also may produce a friable halo surrounding the conduits that may be removed by additional mechanical processes. These observations stress the importance of matrix permeability in eogenetic karst and suggest new concepts may be necessary to describe how conduits develop within these porous rocks.

Extinct Florida Spectacled Bear Tremarctos floridanus (Gidley) from Central Tennessee, 1967, Guilday John E. , Irving David C.

Geomorphology and geologic structure; Straits of Florida, 1970, Malloy R. J. , Hurley R. J. ,

Bathymetric map, seismic reflection profiles, arcer profiles, bottom features, sediment distribution, faults, karst-like topography

Notes on the Occurence of the Snail, Euglandina rosea, in Caves of Northwestern Florida, 1971, Franz Richard, Lee David S. , Stifel Peter B.

Effect of late Pleistocene karst topography on Holocene sedimentation and biota, lower Florida Keys, 1971, Dodd Jr, Siemers Ct,

Thermal stratification and annual heat budget of a Florida sinkhole lake, 1972, Nordlie Frank,

Branchiobdellids (Annelida: Clitellata) from some Eastern North American caves, with descriptions of new species of the Genus Cambarincola., 1973, Holt Perry C.

Branchiobdellids are found as epizoites on crustaceans of the orders Isopoda and Decapoda (cambarine crayfishes) in caves of eastern North America. Species that may be considered as troglobites, since they are not known from epigean waters, appear to be confirmed to truly troglobitic isopods and possibly a few troglobitic crayfishes from Florida and the Tennessee-Kentucky Highland Rim cave belt. The majority of the records of branchiobdellids from caves are of representatives of common epigean forms epizootic un crayfishes. Cross-referenced lists of branchiobdellids, their hosts and cave localities are presented. Some of the new species described are apparently troglobitic or troglophilic, but they present no consistent phylogenetic or geographical pattern and separate origins for them from primitive stocks of the genus Cambarincola are postulated.

Branchiobdellids (Annelida: Clitellata) from some Eastern North American caves, with descriptions of new species of the Genus Cambarincola., 1973, Holt Perry C.

Branchiobdellids are found as epizoites on crustaceans of the orders Isopoda and Decapoda (cambarine crayfishes) in caves of eastern North America. Species that may be considered as troglobites, since they are not known from epigean waters, appear to be confirmed to truly troglobitic isopods and possibly a few troglobitic crayfishes from Florida and the Tennessee-Kentucky Highland Rim cave belt. The majority of the records of branchiobdellids from caves are of representatives of common epigean forms epizootic un crayfishes. Cross-referenced lists of branchiobdellids, their hosts and cave localities are presented. Some of the new species described are apparently troglobitic or troglophilic, but they present no consistent phylogenetic or geographical pattern and separate origins for them from primitive stocks of the genus Cambarincola are postulated.

Observations on the Mating Behavior of the Gray Bat of the Eastern Pipistrelle in Northwestern Florida, 1976, Lee, David S.

The Geothermal nature of the Floridan Plateau, 1977, Smith Douglass L. , Griffin George M.

Hydrogeology related to geothermal conditions of the Floridan Plateau -- Geologic and geomorphic setting -- The principal artesian zone -- The Boulder zone -- Injection sites in Florida -- The Geothermal regime of the Floridan Plateau -- Vertical temperature profiles in Floridan Aquifer system, geographic distribution of temperature in Floridan Aquifer system -- Surface evidence of thermal upwelling -- Humble-Lowndes-Treadwell No. 1 -- Warm mineral springs sinkhole -- The Mud hole submarine spring -- Comparison of theoretical and field studies -- The Dolomite question and cavity formation, Geothermal gradients below the Floridan Aquifer system -- Heat flow in Florida oil test holes and indications of oceanic crust beneath the Southern Florida-Bahamas Platform -- Spatial distribution of ground water temperature in South Florida -- Regional significance of Florida heat flow values -- Thermal model for the Florida crust -- A Model of subsidence with inhomogeneous heat production.

A Sabertooth Cat Smilodon floridanus (Leidy), from Hurricane River Cave, Northwest Arkansas, 1980, Hawksley Oscar, Yongsteadt Norman W. , Youngsteadt Jean O.

Origin of the epeirogenic uplift of Pliocene-Pleistocene beach ridges in Florida and development of the Florida karst, 1984, Opdyke Neil D. , Spangler D. P. , Smith D. L. , Jones D. S. , Lindquist R. C. ,

Marine fossils of Pleistocene age are known to occur in beach ridges near the border of northern Florida and southern Georgia at elevations of between 42 and 49 m above mean sea level. No evidence exists for a massive melt-off of glacial ice, which would be required to raise sea level to these elevations. Florida, therefore, must have been uplifted epeirogenically during the Pleistocene. Measurement of dissolved solids in Florida's springs demonstrates that the karst area is losing a minimum of 1.2 X 10 6 m 3 /yr of limestone through spring flow, the equivalent of 1 m of surficial limestone every 38,000 yr. This loss has led to an isostatic uplift of the north-central part of the Florida peninsula of at least 36 m during the Pleistocene and Holocene, which agrees with observed elevations of marine terraces.--Modified journal abstract

Water development for phosphate mining in a karst setting in Florida_'a complex environmental problem, 1989, Lamoreaux P. E. ,

SMALL-SCALE RETROSPECTIVE GROUND-WATER MONITORING STUDY FOR SIMAZINE IN DIFFERENT HYDROGEOLOGICAL SETTINGS, 1991, Roux P. H. , Hall R. L. , Ross R. H. ,

A ground water monitoring study was conducted for the triazine herbicide simazine at 11 sites in the United States. The study used carefully selected, small-scale sites (average size: about 33 acres) with documented product use and sensitive hydrogeological settings. The sites selected were Tulare County, California (two sites); Fresno County, California; Sussex County, Delaware; Hardee and Palm Beach counties, Florida; Winnebago County, Illinois; Jackson County, Indiana; Van Buren and Berrien counties, Michigan; and Jefferson County, West Virginia. These sites satisfied the following criteria: a history of simazine use, including the year prior to the start of the study; permeable soil and vadose zone; shallow depth to water; no restrictive soil layers above the water table; and gentle slopes not exceeding 2 percent. A variety of crop types, climates, and irrigation practices were included. Monitoring well clusters (shallow and deep) were installed at each site except in California and West Virginia, where only shallow wells were installed. Simazine was monitored at these sites at quarterly intervals for a two-year period during 1986-1988. The results of the study showed that out of 153 samples analyzed, 45 samples showed simazine detections. A substantial majority of the detections (32 out of 45) occurred in Tulare, Fresno, and Jefferson counties. The detections in these areas were attributed to mechanisms other than leaching, such as drainage wells, karst areas, surface water recharge, or point source problems. An additional 11 detections in Van Buren County were apparently due to an unknown upgradient source. Only one detection (in Palm Beach County, Florida) near the screening level of 0.1 ppb was attributed to possible leaching. The results of this investigation support the hypothesis that simazine does not leach significantly under field use conditions

PALUSTRINE CARBONATES AND THE FLORIDA EVERGLADES - TOWARDS AN EXPOSURE INDEX FOR THE FRESH-WATER ENVIRONMENT, 1992, Platt N. H. , Wright V. P. ,

Palustrine carbonates are shallow fresh-water deposits showing evidence of subaqueous deposition and subaerial exposure. These facies are common in the geological record. The intensity of modification is highly variable depending on the climate and the length of emergence. Palustrine limestones have previously been interpreted as marginal lacustrine deposits from fluctuating, low-salinity carbonate lakes, but several problems remain with existing facies models: 1) palustrine carbonates possess a lacustrine biota but commonly display fabrics similar to those of calcretes and peritidal carbonates; 2) the co-occurrence of calcrete horizons and karst-like cavities is somewhat unusual and appears to indicate contemporaneous carbonate precipitation and dissolution in the vadose zone; 3) the dominance of gray colors indicates water-saturation, apparently inconsistent with the evidence for strong desiccation overprint; 4) profundal lake deposits are generally absent from palustrine sequences, and sublittoral facies commonly make up only a small proportion of total thicknesses; 5) no good modem analogue has been identified for the palustrine environment. Analogy with the Florida Everglades suggests a re-interpretation of palustrine limestones, not as pedogenically modified lake margin facies but as the deposits of extensive, very shallow carbonate marshes. The distribution of environments in the Everglades is determined by the local hydrology, reflecting the control of seasonal water-level fluctuations and topography. Climate and topography were the main controls on deposition of ancient palustrine carbonates. As in peritidal sequences, aggradational cycles are capped by a range of lithologies (evaporites, desiccation and microkarst breccias, calcretes, lignite or coal horizons etc.), permitting interpretation of the climate. Careful analysis of lateral facies variations may permit reconstruction of subtle topography. Consideration of the Florida Everglades as a modem analogue for the palustrine environment has suggested the development of an exposure index for fresh-water carbonates