Welcome again to another episode of the Sunshine Republic. Today we'll continue on our examination of the southernmost state, which is a guidebook written in the late 1920s. About the state of Florida. Let's continue with geology and paleontology. The far reaching Floridian plateau includes not only the state, but an even greater surrounding area that lies less than 50 fathoms beneath. The Atlantic Ocean and the Gulf of Mexico. primarily an offspring of the sea and bearing the marks of its marine parentage. plateau was built up largely during the most recent of five geologic eras, and is the youngest part of the United States and land infant but 45 million years old. During the convulsive age of mountain building, the Floridian plateau remained comparatively calm, only rising and falling in a rolling motion. The down dip into the Gulf of Mexico. Process still continues. The last 25,000 years the plateau being on an axis that runs obliquely up the peninsula from Key West to a point below Fernandina. has lifted six feet at Miami dropped 30 feet at Pensacola Paleozoic Era of Earth history.
The area that has now Mississippi Valley was a vast sea east of this in the Appalachian region, lay the landmass to which is now attached the Floridian plateau the hills of Florida are not part of the Appalachian Mountains stand out principally because the surrounding material has settled or eroded away. The Crystalline rock that outcrops in Georgia is not found in Florida, except for deeply buried fragments. Neither do the subsurface waters that feed the state's springs and artesian wells originate in the Appalachian Mountains. Nor is the Peninsula a great coral reef as was once believed. less than 1% of its structure is Coral. Although the foundation rocks of Florida are covered with a stone blanket of marine deposits at least 4000 feet deep. Geologists surmise that they are probably folded and wrinkled in much the same way as our similar rocks in the Piedmont plateau. which extends from the Hudson River to Alabama.
The layers of marine sediment that rests upon the basement rocks were formed when the entire section was beneath the sea, composed for the most part of the skeletons of microscopic sea animals during the Triassic, Jurassic, Lower Cretaceous periods in the Mesozoic era. The state of Korea was above the waters was submerged many times during the Cenozoic recent age of mammals at no time, so far as can be learned, how did the land ever rise very high above sea level? Where did the sea ever cover the land to any great depth? The warm shallow seas that repeatedly covered the area were ideally suited for men of Pharaoh Farah. These tiny marine animals some too small to be seen by the naked eye lived and died by the millions in tropical waters. While alive they were protected by shells alive. When they died, the shells sank to the floor of the ocean to form layers of limestone, which hundreds of feet thick.
During the EOC an oligo scene epochs, the strata were composed almost entirely of this matter and the formations of these periods are nearly pure limestone. During the MIO scene, however, fine sand was washed down from the mountains of Georgia and Alabama, and was deposited on the Florida plateau to form Sandy limestone. And later much clay drifted south to settle over the state area and complete its stratified layers. Thus, the foundation rocks are separated from the earliest exposed strata, massive limestone 4000 feet thick by layers of red, white and black clay. Gentle up arching of the EOC and older rocks had begun before the last of these deposits was made in this domain. Finally, the structure a list which, despite torrential rains that battered and slashed to beat it down to 150 feet above sea level to form an island around presence or color. Eventually, when the Suwannee strait the North closed became a peninsula less than half the size of the Floridian plateau. Part of the North American landmass. tip of the peninsula extended at one time only to the lower rim of Lake Okeechobee. And far to the south. From that point, another formation emerged from the upbuilding of live coral and submerged oolitic rock.
Gradually, wind and waves rolled up barriers along the Atlantic and Gulf Coast's extending the peninsula towards the coral reefs and eventually forming dunes that shut out the sea. enclosed area ranked with marine plant life became a freshwater basin and its decaying vegetation through the centuries into peatlands now comprise the Everglades. Survey made along the Florida Reef in 1846 by Timothy, but Conrad and followed by Louis Agassiz Eve original ground for the belief that the entire peninsula of Florida was a coral formation. This theory was incorporated by Joseph McCarthy in his excellent textbook elements of geology in 1878. The belief continued until 1886. Angell, Ohio print determined that the progressive growth of the peninsula as far south as Lake Okeechobee was due to a combination of sedimentation. And upheaval.
Geologically, Florida strata date back only to the tertiary or later periods of the Santos era, embracing the Eocene Oligocene Miocene, Pliocene epics. Under familiar names these layers supply in an inexhaustible source of road material in Florida is lucrative phosphate industry account for its pitted topography, and provide underground reservoirs that ashore to all sections and independent supply of fresh water from local rainfall. Kala limestone of the Eocene epic, oldest exposed sediment in the state outcrops over a large section around we'll call them switching north to Suwannee River and south to the Withlacoochee River. This limestone underlies the entire state except for the extreme western portion. Pure White to cream colored granular rock, varying in thickness from 50 to 500 feet consists almost entirely of carbonate alive, chiefly composed of composed of four minute Farah, as are the older strata upon which it rests. Also contains fossil coral, sea urchins, mollusks, occasionally a vertebrate sea mammal and mass zoo Gadon, early ancestor of the whale.
Ariana and Glendon limestones and Byram Laurel rests on the Ocala limestone and belong to the Oligocene epic. They correspond to the strata known as the Vicksburg group and Mississippi and Alabama. They appear in Florida only in the vicinity of Mariana the exception of a curved strip, the Glendon stone on either side of Suwannee River near Ellenville, Haryana limestone, soft white rock, there's to a dirty grey. Blend in limestone is hard, and its color runs from yellow to a pinkish hue. By remarkable consists of soft fine grain Sandy yellow limestone, the first two are quarried on a small scale and are used in construction of chimneys. Era of mountain building in the western part of North America during the Miocene epic few changes in the contour and general outline of Florida. Six different layers of limestone sand and marble are then deposited. Tampa limestone widespread but missing in many areas. Shoal River Formation Chipola Formation The Oak Grove sands in the northwestern part of the state, the chapter watch a formation found in both the Panhandle and inland from Charlotte Harbor, the Hawthorne formation, so widespread but thin and much of it is eroded away.
Most important Miocene strata are the cream to white colored limestones of the Tampa and Hawthorne formations exposed over large areas. Former is essentially a marine and estuarine formation the ladder chiefly inland deposit Tampa limestone is used in the manufacture of cement and both are used for making quick live often contains commercial deposits of fuller's earth. Deposits are divided into the Caloosahatchee Mauro Citronelle formation, bone Valley gravel and the Alachua formation. First of these consisting of fine sand, lime ooze and shells, laid down in shallow saltwater when the state was submerged, calm sea Citronelle formation appears to have been deposited as a large delta the bone Valley gravel similarly from a estuarine source bone valley that lateral formations contain a great number of land, animal bones and phosphatic material from the hawthorn decayed phosphate deposits, such as calcium phosphate, calcium carbonate and other minerals derived from the fossil remains of extinct land and water animals. Electrode deposits mined in the Dunellen region, supply hard rock phosphate from the bone Valley gravel in the Bartow region was pebble phosphate. Phosphate was discovered on the Peace River in 1884 by Jay Francis LeBaron was not commercially developed until 1887. Colonel TS Morehead managed to raise the capital were barren had failed. Place the scene first epic of the coronary period of the Senate zoic era, also known as the age of man, saw the formation of both land and water deposits, alluvia and windblown sand were laid down away from the ocean in the sea were built up shell marl. Coquina that furnished the early Spaniards with an easily worked building style soft lytic rock quarry of limestone.
The greater part of the population of Florida occupies the Pensacola terrorists formation of place to scene origin and this terrorists are the cities of Fernandina St Augustine, Jacksonville, Miami, Fort Myers Bradenton, Tampa, St. Petersburg and Pensacola. Florida has its share of geological mysteries. One that gave rise to much speculation was a column of smoke and a red glare that appeared in a sky above the impenetrable coolest swap in August 1886. disappeared immediately after the Charleston earthquake. Geologists infer that it was caused by the ignition escaping natural gas by lightning that the earthquake sealed the vent and thus extinguish the flames. More difficult to explain. One spectacular is a row of round holes a few miles north of Brooksville each about 36 inches in diameter, filled almost to the top with drifted sand and decaying vegetation. These chimneys as they are locally named our block and around the top show no indication of volcanic heat.
Ballast Point in Tampa geocodes are frequently uncovered. These are little knots of stone with quartz like interiors, from light agate tents to jet black geode is in detached formation and its accidental presence in the sign Lex beds at Ballast Point. attributed to a tendency of nature to form concretions out of whatever substance is at hand. Only known similar specimens are found in the Mediterranean and Aegean seas during the first two periods of the tertiary era the only living creatures in Florida were marine animals.
Although the tertiary produced in other parts of the continent, the dinosaurs that are associated with prehistoric life. Florida area was submerged at this time and the corresponding formation call a limestone contains evidence of one mammal, a whale like sea monster, known as Basilosaurus. Formations of the last two periods of the tertiary the Miocene and Pliocene eras contain evidence that the state was then inhabited by strange beasts that found their way to the peninsula for many parts of the world. The Allen bluff beds of the Hawthorne formation in Leon Gadsden and Alachua County's been found the bones and teeth of deer, three toed horses, camels, giant pigs and rhinoceroses. Were not predatory types, however, and had man inhabited the state at this time he would have feared but one carnivorous animal prowling beasts akin to both the modern Wolf and dog.
Number of significant plant fossils have been found in the Allen bluff bed between the Chipola and chapter with watching formations among the 13 species, positively identified fan palm, red fruit, satin wood, or wood, camphor, thorn, Elm and persimmon all of which are adapted to the present habitat of the region. And species indicated the floor was predominantly tropical, some additions from temperate climates the three toed horse was paribus can be traced through several varieties. The hipparion, three toed horse of the Pliocene. Hiperion, however, was not in the direct line that led to the development of the modern horse. It was a branch that has since disappeared. It's not until the Pleistocene era that fossils of Equus the prehistoric one Toad horse, is often called the Homo Sapien. And horse family appear in Florida deposits. is seen deposits following in point of geological time directly after the Miocene 10 an even greater abundance of fossil animal remains phosphate mines of Alachua Levi and Polk Counties yielded rich stores to the Florida paleontologist.
The fauna of this age differs greatly from that in modern times. It was in the Pleistocene that the mastodons made their way from the old world by way of Asia, even at the very beginning of the age, firmly established on the peninsula serrated tooth Mastodon, a great elephant like creature with a short trunk and four tusks, under from India halfway around the world before reaching Florida. With the Pleistocene era there came a multitude of both great and small animals, as will probably never be found in one region again. Great ice sheet at this time was advancing South from North Pole and covering the northern part of the United States and all of Canada. It was a glacial mass that destroyed vegetation and drove animal life before it began. herbivorous beasts sought green pastures in the warmer territories in the south, and countless 1000s invaded Florida. Camels, horses mammoths, huge sloths armadillos and peccary has roamed the state. Cropping grass and stripping leaves the Pleistocene trees.
After them came the beasts of prey, Saber toothed Tigers, wolves and lions, which made life precarious for the vegetarians. Even these animals bear a resemblance to the modern foreigner of South America and Africa, and students of ancient life I present this as evidence for the theory that camels originated in America and later made their way to the old world long before man, possibly following the animal trail. That found its way to the new world. Most important deposits of the Pleistocene era in the state are the Melbourne bone beds, a series of patches along the east coast, tending the bones of extinct animals just as they were buried 1000s of years ago, beneath shifting sand. Investigation of these beds has been carried on from time to time. The posits are so rich, that it will be many years before all that material can be assembled and classified. Logical information on Florida is not to be to be obtained from the mountains. outcroppings can be studied with comparatively little effort and expense strapped up 1000s of feet below the surface.
Usually, the expense of such operations has made geological research in this state and incident of commercial enterprise is in a deep well boring to Marion County. Thus, we intermittently have geologists been able to study that part of the Earth's history written in the rocks, soils, and waters, Florida. We conclude this section about the geology of Florida from the 1929 southernmost state guide written by the Civilian Conservation Corps in our next episode, we will be examining the chapter the Isle of flowers. So thank you very much for joining us on the sunshine Republic podcast and we'll see you in our next episode for the Isle of flowers
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