Any in-depth study of the geology of the Everglades area reveals that the local sedimentary framework differs greatly from those seen on the adjacent Floridian Peninsula and the southeastern United States. This unique and distinctive geology is the direct result of almost continuous carbonate sedimentary deposition within a semi-enclosed tropical sea, with each preserved sea floor producing sets of environments and lithofacies that ultimately consolidated into the formations that underlie the Everglades Basin. Over the past hundred years, scientists have become aware of the difficulty in interpreting the geology of such a homogeneous carbonate area. This, coupled with the paucity of exposures within the harsh Everglades swampland, has made southern Florida the last heavily-populated area of the U.S. to be fully explored geologically. Our present understanding of the underpinnings of the Everglades results from the labors, sacrifices, and insights of some of the most dedicated scientists in the history of American geology. These rugged explorers, particularly the early workers, braved the heat, disease-carrying mosquitoes, and dangerous conditions to gather, incrementally, the information that we have assembled here.
Geological and Paleontological Exploration in the Everglades Region.
Considering that southern Florida now houses one of the largest population centers in the United States, it seems amazing that, just a little over a century ago, the area was essentially unexplored. In early 1886, Angelo Heilprin of the Philadelphia Academy of Natural Sciences undertook the first geologic and geographic exploration of the areas around Lake Okeechobee and the Caloosahatchee River. Accompanied by the sponsors of the expedition (Joseph Willcox and Charles H. Brock of Philadelphia), Captain Frank Strobhar, and the cook Moses Natteal, Heilprin investigated the āā¦ mysterious body of water ā Okeechobee ā¦ā on the schooner āRambler.ā This first geologic research was published later in 1886 (first draft; second draft published in 1887) by the Wagner Free Institute of Science of Philadelphia, and Heilprin expounded at length about his adventures in the Okeechobee Wilderness. Besides giving the first physiographic description of the northern Everglades region, Heilprin also described new species of living snakes and fishes and some of the more spectacular Everglades fossil shells. This pioneer work excited the scientific community and set the stage for a flurry of geologic and paleontologic research.
For more than a decade, all publications on the geology and paleontology of the Everglades stemmed from a single individual, William Healey Dall of the U.S. Geologic Survey and the Smithsonian Institution (honorary curator). After a preliminary report on the geology of Florida (1887), Dall initiated the Contributions to the Tertiary Fauna of Florida, a series of large monographic works that was published between 1890 and 1903 (also by the Wagner Free Institute of Science). Within this same series (1892), Dall also published the first geologic map of Florida, with the Everglades area being left conspicuously blank. Nothing of this scope has ever been attempted since, and the series stands out as one of the great masterpieces of American geology and paleontology. Dall continued publishing works on Floridian geology (a large monograph on the Tampa Oligocene and early Miocene agatized shells) until 1915. Without doubt, William Healey Dall can be considered the āFather of Everglades Geology and Paleontology.ā
Following Heilprin and Dall's pioneer works, the newly established Florida Geological Survey (formed 1907) immediately began publishing a series of annual reports on exploration of the regional geology. One of the most important of these was G.C. Matson and F.G. Clapp's 1909 preliminary stratigraphic scheme for the Floridian Peninsula (Annual Report 2). Taking into account the lack of natural exposures in the Everglades area, Matson and Clapp's work concentrated on the northern half of the state. In the same year, Samuel Sanford (1909) described and named the surficial limestones of coastal southeastern Florida and the Florida Keys. A decade later, E.H. Sellards (1919) published the first geologic section across the Everglades in the Florida Geological Survey Annual Report 12. As new drainage canals were being dug across the Everglades at that time, Sellards and his coworkers were able to retrieve the first data on what geologic formations existed below the surface peat and muck. All the new information accumulated by the Florida Geological Survey was ultimately synthesized by C.W. Cooke and S. Mossom (1929), who published the first comprehensive work on the geology of the entire state (Annual Report 20). Cooke and Mossom were also the first geologists to traverse the Tamiami Trail. In less than 30 years, the Everglades region had gone from terra incognita to being part of the known geologic continuum of the Floridian Peninsula.
As Dall had dominated the 1890s with his prolific works, Wendell C. Mansfield dominated the 1930s with a similar plethora of research and publications. Although his earlier works concentrated on the geology and paleontology of northern Florida, Mansfield began to investigate (in the early 1930s) fossils from newly exposed areas within the Everglades Basin. With his publications in 1931 and 1932 on new fossil mollusks and echinoderms, Mansfield was the first person to discover and name new paleospecies from the southern part of the Everglades. His last work (published posthumously in 1939), which dealt with the stratigraphy of the Everglades Basin, set the stage for all modern studies of the regional geologic framework. Mansfield and Dall, together, named hundreds of important new molluscan stratigraphic index fossils, and their names as the authors of species of fossil shells can be seen throughout this book. In addition to Mansfield, several other important workers described new Everglades molluscan index fossils in the 1930s, including Helen I. Tucker (later TuckerāRowland), Druid Wilson (1932, 1933) and Maxwell Smith (1936). Most of the discoveries of Tucker and Wilson came from two sources: the construction of the Hoover Dike around Lake Okeechobee following the devastating 1928 hurricane and some of the first commercial quarries in southern Florida near Acline, Lee County.
During the span of World War II, there was a marked drop in the number of publications on Everglades geology. Besides a few scattered papers on new fossil mollusk species by Maxwell Smith and Thomas McGinty (in 1940, before the United States' entry into the war), only a single large work was produced that dealt with the regional geology. This impressive monograph, The Geology of Florida by C.W. Cooke (1945), was the culmination and synthesis of all previous research on the geology of the entire State. Although now outdated in content, the book is still a valuable resource for the geology of southern Florida, giving detailed descriptions and illustrations of stratigraphic sections now long lost. Cooke arranged his book geochronologically and illustrated many key index fossils, and we have chosen to use his monograph as a model for this book. Along with Gerald Parker, C.W. Cooke also published the first major study of the groundwater and geologic framework of southern Florida (1944).
With the end of World War II, geologic research in the Everglades region resumed with an intensity not seen since the 1930s. Within a 5-year span, three classic works on the regional geology and paleontology were published: Axel Olsson and Anne Harbison's large monograph on the molluscan paleofauna of St. Petersburg (1953, accompanied by smaller works by Fargo and Pilsbry), Gerald G. Parker's tome on the hydrogeology of the Everglades area (1955; with detailed core logs and deep subsurface data), and Jules DuBar's detailed study on the stratigraphy of the Caloosahatchee River area (1958). These three works represented a quantum leap in our knowledge of the Everglades. The 1960s saw a flurry of commercial development and road building within the Everglades area. Probably the most conspicuous project was the construction of the highway named āAlligator Alleyā in Broward and Collier Counties in the early 1960s (now part of Interstate Highway 75, running from Fort Lauderdale to Naples). The preliminary canal dredgings and road-fill excavations produced the first deep transect across the central Everglades. This was a windfall for the regional geologists and paleontologists, allowing them to bulk sample stratigraphic units that had previously been inaccessible or known only from drill cores. New stratigraphic index fossils from āAlligator Alleyā and around Lake Okeechobee were reported in a series of publications by Axel Olsson (1967) and Richard E. Petit (1964, 1968) and by Emily Vokes (in the Tulane Studies in Geology series; i.e., 1963, 1965, 1966). With the new data from canal excavations around southwestern Florida, Muriel Hunter (1968) was able to offer the first accurate interpretation of the late Miocene and Pliocene stratigraphy of the Everglades region. The same year (1968) also saw the first in-depth study of the geology and origin of the Florida Keys by J.E. Hoffmeister and H.G. Multer. This classic work complemented Hoffmeister and Multer's earlier study (with K.W. Stockman, 1967) on the oƶlitic limestones of Dade County and the Florida Keys (Miami Formation). Throughout the 1960s, the deepening and channelizing of the Kissimmee River was undertaken by the Army Corps of Engineers. The exposure of sediments in the spoil banks along the Kissimmee River allowed researchers to study, for the first time, the unusual and highly endemic fossil mollusks of that area (the Kissimmee Embayment).
The 1970s marked the beginning of major housing development and road building around the Everglades area, allowing accessibility to many new research sites, particularly along the Kissimmee River in the northern Everglades. At that same time, the demand for fill dirt (primarily for housing construction) produced the economic incentives for large quarries to be excavated all along the southwestern and southern Everglades area. Some of the most important of these included the Ashland Petroleum and Asphalt Corporation (APAC) quarry at Sarasota (originally the Warren Brothers and Richardson pit), the Mule Pen quarry at East Naples (originally a mule breeding site and later the Florida Rock Industries Naples Quarry), and the quarries at Sunniland. Many important new index fossils were described from these sites, including new mollusks (S.C. Hollister, 1971; Emily Vokes, 1975, 1976) and corals (N.E. Weisbord, 1974). All the new data accumulated during the 1950s and 1960s allowed Jules DuBar to build upon his early work on the Caloosahatchee area and create the first workable stratigraphic scheme for the entire Neogene of the Everglades (1974). This work was particularly important because of its descriptions and clarifications of the then poorly known Pleistocene formations. Further research on the Pleistocene and Holocene was undertaken by Enos and Perkins (1977), who published the first detailed study of Quaternary depositional environments in the Everglades and Florida Bay.
The explosion of housing development that started in the 1970s, with increased numbers of landfill quarries and canal digs, escalated even more in southern Florida during the 1980s. Although a disaster for the ecosystems within the Everglades and the peripheral areas, the profusion of new excavations offered geologists many opportunities to study subsurface areas that were previously inaccessible. One of the more important discoveries that resulted from this land development was the uncovering of large, complex Pliocene coral reef systems along southwestern Florida. From data collected in canal digs and quarries in that area, J.F. Meeder was the first to describe the Pliocene reef limestones and associated carbonate facies found along the Collier County and Lee County coasts (1980, based upon his previous work published in a geology field trip guide in 1979). Subsequently, the senior author discovered a āmirror-imageā system of Pliocene coral reefs under Dade County (the āBird Road Digā of Miami, 1986). When the data on the two contemporaneous reef tracts were later combined, it was shown that the east and west coast systems constituted a single, large contiguous coralline feature, the Everglades Pseudoatoll (Petuch, 1987; for details see Chapter 6 in this book).
Resulting from research in the APAC quarry at Sarasota, the senior author published the first reference stratigraphic column for the Pliocene of southern Florida earlier in the decade (Petuch, 1982; reproduced here in Chapter 5). The first attempt at bringing together geological, environmental, and anthropological studies into a single volume was undertaken by the Miami Geological Society in 1984, with the publication of Environments of South Florida, Past and Present (Patrick J. Gleason, editor). The hydrogeology of the east coast Pliocene reef tracts was studied extensively from 1985 to 1986, and the data were subsequently published by L.J. Swayze and W.L. Miller in 1987 (U.S. Geological Survey, Water Resources Division). Thomas M. Scott (Florida Geological Survey) published his large monographic work on the Hawthorn Group of Florida one year later. This ...
