| Ocala Limestone | |
|---|---|
| Stratigraphic range: Eocene | |
 | |
| Type | Geological formation |
| Underlies | Suwannee Limestone (Oligocene) |
| Overlies | Avon Park Formation |
| Thickness | Lafayette-Sumter counties |
| Lithology | |
| Primary | limestone and dolomite |
| Location | |
| Region | North Florida |
| Country |  United States |
| Type section | |
| Named for | Ocala, Florida (city) |
The Ocala Limestone is a late Eocene geologic formation of exposed limestones near Ocala, Marion County, Florida.
Period : Paleogene
Epoch : Late Eocene
Faunal stage : Late Clarkforkian through early Orellan
Absolute Age : ~55.8 to ~33.9 mya, calculates to a period of approximately 21.9 million years
The Ocala Limestone is at or near the surface within the Ocala Karst District located in west-central to the northwestern part of the peninsula. It is also within the Dougherty Plain District in the north-central panhandle where it easily forms karsts. These karsts often have several feet (meters) of relief which dramatically influence the topography of the Ocala Karst District and the Dougherty Plain District. The area is abundant with disappearing streams and springs.
Formerly a geologic group, Ocala Limestone was downgraded to formation status by T.M. Scott in 1991. [1] The Ocala Limestone consists of almost pure limestones with occasional dolomites. It can be subdivided into both lower and upper facies with the lower facies composed of a whitish to cream-colored, fine to medium grained, poorly to moderately hard, fossil rich grainstone and packstone. The upper Ocala is white and somewhat weak and poorly sorted. Its extremely fossil rich grainstone, packstone and wackestone and some chert is common in the upper facies. Its permeable and transmissive properties allow it to form a vital portion of the Floridan Aquifer.
The Ocala Limestone overlies the Avon Park Formation and forms part of the Floridan Aquifer System. (USGS)
The Floridan aquifer system, composed of the Upper and Lower Floridan aquifers, is a sequence of Paleogene carbonate rock which spans an area of about 100,000 square miles (260,000 km2) in the southeastern United States. It underlies the entire state of Florida and parts of Alabama, Georgia, Mississippi, and South Carolina.
The Cody Scarp or Cody Escarpment is located in north and north central Florida United States. It is a relict scarp and ancient persistent topographical feature formed from an ancient early Pleistocene shorelines of ~1.8 million to 10,000 years BP during interglacial periods. The Cody Scarp has a slope of 5% to 12%.
The Dakota is a sedimentary geologic unit name of formation and group rank in Midwestern North America. The Dakota units are generally composed of sandstones, mudstones, clays, and shales deposited in the Mid-Cretaceous opening of the Western Interior Seaway. The usage of the name Dakota for this particular Albian-Cenomanian strata is exceptionally widespread; from British Columbia and Alberta to Montana and Wisconsin to Colorado and Kansas to Utah and Arizona. It is famous for producing massive colorful rock formations in the Rocky Mountains and the Great Plains of the United States, and for preserving both dinosaur footprints and early deciduous tree leaves.
The Debolt Formation is a stratigraphical unit of Meramecian age in the Western Canadian Sedimentary Basin.
The Torreya Formation is a Miocene geologic formation with an outcrop in North Florida. It is within the Hawthorn Group.
The Suwannee Limestone is an Early Oligocene geologic formation of exposed limestones in North Florida, United States.
The Avon Park Formation is a Middle Eocene geologic formation and is the oldest exposed sediments in Florida, United States.
The Coosawhatchie Formation is a Miocene geologic formation with an outcrop in North Florida. It is within the Hawthorn Group.
The St. Marks Formation is a Miocene geologic formation in the eastern Florida Panhandle.
The Arcadia Formation and its sub-unit, the Tampa Member, are Late Oligocene geologic formations in North Florida, United States. It is part of the Hawthorn Group.
The Peace River Formation is a Late Oligocene to Early Miocene geologic formation in the west-central Florida peninsula.
Orange Island is the earliest emergent landmass of Florida dating from the middle Rupelian ~33.9—28.4 Ma. geologic stage of the Early Oligocene epoch and named for Orange County, Florida, United States of America.
The Tamiami Formation is a Late Miocene to Pliocene geologic formation in the southwest Florida peninsula.
The Bluefield Formation is a geologic formation in West Virginia. It preserves fossils dating back to the Mississippian subperiod of the Carboniferous period. Sediments of this age formed along a large marine basin lying in the region of what is now the Appalachian Plateau. The Bluefield Formation is the lowest section of the primarily siliciclastic Mauch Chunk Group, underlying the Stony Gap Sandstone Member of the Hinton Formation and overlying the limestone-rich Greenbrier Group.
The Lexington Limestone is a prominent geologic formation that constitutes a large part of the late Ordovician bedrock of the inner Bluegrass region in Kentucky. Named after the city of Lexington, the geologic formation has heavily influenced both the surface topography and economy of the region.
The Montoya Group is a group of geologic formations in westernmost Texas and southern New Mexico. It preserves fossils dating back to the late Ordovician period.
The geology of Somalia is built on more than 700 million year old igneous and metamorphic crystalline basement rock, which outcrops at some places in northern Somalia. These ancient units are covered in thick layers of sedimentary rock formed in the last 200 million years and influenced by the rifting apart of the Somali Plate and the Arabian Plate. The geology of Somaliland, the de facto independent country recognized as part of Somalia, is to some degree better studied than that of Somalia as a whole. Instability related to the Somali Civil War and previous political upheaval has limited geologic research in places while heightening the importance of groundwater resources for vulnerable populations.
The geology of Somaliland is very closely related to the geology of Somalia. Somaliland is a de facto independent country within the boundaries that the international community recognizes as Somalia. Because it encompasses the former territory of British Somaliland, the region is historically better researched than former Italian Somaliland. Somaliland is built on more than 700 million year old igneous and metamorphic crystalline basement rock.. These ancient units are covered in thick layers of sedimentary rock formed in the last 200 million years and influenced by the rifting apart of the Somali Plate and the Arabian Plate.
The Algoa Group is one of five geological groups which comprise the coastal Cenozoic geological deposits in South Africa. The Algoa Group contains six formations which range from Middle Eocene to Late Holocene in age.
The geology of Saudi Arabia includes Precambrian igneous and metamorphic basement rocks, exposed across much of the country. Thick sedimentary sequences from the Phanerozoic dominate much of the country's surface and host oil.
