Come Explore Georgia's Natural History
  • Home: Georgias Fossils
  • 1: Georgia's Oldest Fossils; Archaeocyathids, At 513 Million Years Old
  • 2: Trilobites; 500 Million Years Ago
    • 2A; Murray County Stromatolites
    • 2B; A Trilobite Nest in Georgia
  • 3: Geologic Time
  • 4: Georgia's Oldest Vertebrate?
  • 5: Georgia Before the Dinosaurs
    • 5A; Georgia’s Pennsylvanian Plant Fossils
    • 5B: Carpentertypus durhami, Georgia’s Giant Insect, 315 Million Years Ago
    • 5C: Mississippian Trilobites in Northwest Georgia Describing the New Species Australosutura georgiana
    • 5D: Crinoids & Blastoids Of Northwest Georgia
    • 5E; Fossils of Northwest Georgia
  • *New* 5F: Pennsylvanian Plant Fossils of NW Georgia
  • 6: 200 Million Years Ago
  • 6A: Birth of the Atlantic Ocean
  • 7: Cretaceous Georgia, Dinosaurs & more
    • 7A: Georgias Pterosaur
    • 7B: So Many Sharks
    • 7C: Coelecanths
    • 7D: Xiphactinus vetus
    • 7E: Side-necked turtles
    • 7F: Marine Reptiles
    • 7G: Dinosaurs in Georgia
    • 7H: Deinosuchus schwimmeri in Recognition of Dr. David Schwimmer
    • 7I; The Blufftown Formation
    • 7J: New Species of Cretaceous Flowers Reported From Crawford County
    • 7K: Field Trip, Chattahoochee River Valley 1980
    • 7L: The Eutaw Formation
    • 7M: The Pio Nono Formation
    • 7N: Plant Fossils of Crawford County, GA
    • 7O; 1914 Report Georgia Plant Fossils From the Upper Cretaceous
    • 7P: Bill Montante's Mega "Gator" Tooth Discovery
  • 8: Suwannee Current, Gulf Trough, & Bridgeboro Limestone
  • 9: 60 million years ago, The Paleocene's Clayton Formation, A Report; By Hank Josey
    • 9A: The Georgia Turtle
    • 9B; Sassafras Hill Quarry Huber Formation Plant Fossils in Kaolin
  • 10: The Eocene; Georgia's Oldest Mammals
    • 10A: The Origins of Whales
  • 11: A Whale For Georgia
  • 12: Basilosaurids; The First Modern Whales
    • 12A: Basilosaurus cetoides
    • 12B: Basilotritus
    • 12C: Cynthiacetus (Revised)
    • 12D: Chrysocetus
    • 12E: The Redmond Mandible of Albany Ga
    • 12F: Houston County's Famous Great Whale Goes to the Smithsonian
  • 13: Ziggy and The Museum of Arts & Sciences, Macon, GA
  • 14: Late Eocene
    • 14A: Eocene Fossils & Stratigraphy
    • 14B; Fossils, Impacts, & Tektites Dating the Clinchfield Formation
    • 14C: The Tivola Limestone
    • 14C1: Oldest Oreodont in the Southeast & Georgia's first!
    • 14D: Twiggs Clay Vertebrates
    • 14E: Ocmulgee Formation Vertebrates
    • 14F; Sandersville Limestone, By Hank Josey
    • 14I: Dating Late Eocene Sediments
    • 14J: Georgia's Tektites; Georgiaites
    • 14K; Shell Bluff; Georgia's Most Historic Paleontology Site
    • 14L; Taylors Bluff, Paleo Paddling the Ocmulgee River
    • 14M; Eocene Terrestrial Mammals From Gordon, GA
    • 14N: Fossil Ridge, A Stratigraphic Study in Oaky Woods Wildlife Management Area
    • 14O; Georgia's First Entelodont
    • 14P: Historic Rich Hill
    • 14Q; Bibb County's Christy Hill, Clinchfield Formation Hilltop
    • 14R: Browns Mount, The Fall Line, Elevations, Uplifts, & Native Middle Georgians
  • 15: Early Oligocene
    • 15A: The Marianna Limestone
    • 15B; The Glendon Limestone
    • 15C: Undiffereniated Oligocene Residuum
    • 15D; Brissus bridgeboroensis; A New Echinoid Species From Georgia’s Bridgeboro Limestone
    • 15E: The Curious Steinkern Sea Biscuits of Red Dog Farm Road
    • 15F: Early Oligocene Gordian Knot
  • 16: Bonaire GA Entelodont
  • 17: The Whale Eating Shark
  • 18: Miocene Epoch; 23.3 to 5.3 Million Years Ago
    • 18A; Miocene Terrestrial Vertebrates
    • 18B; Paul Fell, Rockhouse Cave
    • 18C: The Marks Head Formation
    • 18D: Miocene Terrestrial Vertebrates of the Marks Head Formation
    • 18E: The Statenville Formation
    • 18F: Georgia’s 13 Million Year Old Dugong Metaxytherium calvertense
    • 18G: Gastropod Gulch, Julia Gardner, & Miocene Invertebrates In Decatur County
    • 18H; Bony Bluff, Rocky Ford, Echols County In Southernmost Georgia
  • 19: Pliocene Epoch; 5.3 to 2.5 Million years Ago
    • 19A: Two Small Primitive Horses from Taylor County Advance the Science of Georgia Geology
  • 20: The Pleistocene & Holocene Epochs, The Ice Ages
    • 20A; Clark Quarry's Mammoths & Bison
    • 20B: Pleistocene Vertebrate List
    • 20C: Georgia’s Eolian Dunes
    • 20D: Georgia’s Carolina Bays
    • 20E: Late Pleistocene Significant Events
    • 20F: Southeastern Thermal Enclave
    • 20G; Diamond Back Terrapins
    • 20H; A Kaolin Mine Beaver Dam
    • 20I; Pleistocene Vertebrate Fossils On Georgia’s Piedmont
    • 20J; Watkins Quarry Pleistocene Vertebrates, Glynn County, GA
    • 20K: Pleistocene Vertebrates from Coastal Georgia
    • 20L; Sandy Run Creek Core, Warner Robins, Houston County, GA
    • 20M: Bone Bed, Pleistocene, Coastal Georgia
    • 20N: Caribou & Elk Fossils from Georgia & Alabama
    • 20O; Tapir Veroensis, Walker County, Late Pleistocene
    • 20P; Ladds Pleistocene Vertebrates, Bartow County, GA
  • 21: Humans in Georgia
  • 22: Geology of the Coastal Plain, 1911
    • 22A: 1911 Cretaceous Fossil Locations
    • 22B: 1911 Eocene Fossil Locations
  • 23: GA County Localities, Houston County
  • 24: Science: Natural History & Geology
    • 24A; Podcast; The Tivola Whale of Houston County
    • 24B: Coastal Plain Correlation Chart
    • 24C: Presentation; Oaky Woods Stratigraphy
    • 24D: Physiographic Map of Georgia
    • 24E: Fossils of Oaky Woods
    • 24F: Collections & Stewardship of Georgia’s Fossils
    • 24G: I, Periarchus (A Fossil's Tale)
    • 24H: The Tivola Whales (April 2023 talk to the Mid-Georgia Gem & Mineral Society)
    • 24L: Needed; The Georgia Geologic Survey
    • 24M: Georgiacetus Presentation; A Whale for Georgia
    • 24N: Paul F. Huddlestun PhD, Georgia Coastal Plain Field Investigator >
      • 24N1: Late Eocene & Older... Coastal Plain Stratigraphy
      • 24N2: Gulf Trough Cores, Colquitt County, by Paul Huddlestun
      • 24N3; Washington County Core Logs By Paul Huddlestun
      • 24N4: Coastal Plain Core Logs by Paul F. Huddlestun
      • 24N5: Colquitt Core #6 By Paul Huddlestun
      • 24N6: Colquitt 10 & 7 Core
      • 24N7: Wayne County Core, Manningtown
      • 24N8: Gulf Trough Cores >
        • 24N8-1: Chatham County, Tybee Island Core
        • 24N8-2: Gulf Trough, USGS, Claxton, Evans County Core
        • 24N8-3: Blue Springs Landing Core, Screven County
        • 24N8-4: Toombs County Core, Baxley
    • 24O: Echinoids of Georgia, Cenozoic Era (Sand Dollars & Urchins) >
      • 24O1: Echinoids of Georgia, Cenozoic, By County
    • 24P; Exploring the Paleontology of Southernmost Georgia >
      • 24P1; Seminole County
      • 24P2: Decatur County Fossils & Natural History
      • 24P3: Grady County Blowing Caves, Forest Falls, Fossils & Natural History
  • 25: Education Material
    • 25A: My Field Kit; What You Need In The Field
    • 25B: Meet Crassostrea gigantissima, Georgia's Historic Giant Oyster
    • 25C: The Natural History & Fossils Record of Houston County, GA
    • 25D: Evidence for Evolution in Georgia's Fossil Record... A look at Teeth
    • 25E: Georgia's State Fossil; Shark Teeth
    • 25F: Georgia's Paleontology For Georgia's Classrooms
    • 25G: Library & School Presentations
    • 25H; An Introduction To Fossils; Presentation
  • 26: Georgia's Meteorites
    • 26A: Did I Find A Meteorite?
    • 26B: Georgia's Lost Meteorite
    • 26C: Georgia's Witnessed Meteorite Falls
    • 26D: The Sardis Iron, Georgia's Largest Meteorite

1: Archaeocyathids;
Georgia’s Oldest Fossils At 513 Million Years Old
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By Thomas Thurman

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​Archaeocyathid
means "ancient cups" and they’re Earth’s oldest reef building organisms and at 513 million years old, Georgia’s oldest fossil. There were solitary species as well as reef-building ones. They occur in the Shady dolomite formation of the Cartersville mining district in Bartow County, Georgia.

The fossil is essentially two conical calcium structures, like nestled bowls or cones, connected by vertical walls. The structures are porous, it’s believed that water was drawn or pumped through the pores, nutrients filtered out, and the water expelled into the central cavity. It’s thought that the “body” of the living organism occupied the space between the walls.
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They’re extinct, and we know very little about the living animal but the earliest fossils come from Early Cambrian sediments 525 million years old, in modern Siberia. They diversified dramatically into over a hundred families but at about 516 million years ago they went into a sharp decline. The last known species, Antarcticocyathus webberi, met extinction near the end of the Cambrian about 490 million years ago and is known, as its name suggests, from Antarctica.
 
Some researchers consider them to be coralline sponges, but this is still a matter of debate. Sponges are known to occur at 580 million years ago. Archaeocyathids resist taxonomy and have yet to be properly assigned in the Linnaean scientific classification systems; another matter of ongoing debate.

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From the minds of many…
I want to thank Cam Muskelly, Bill Montante (Tellus Science Museum), Asa Kaplan and Burt Carter for their assistance on this page. These Northwest Georgia Valley & Ridge fossils are from a very different world than the sediments I usually work in south Central Georgia’s Coastal Plain. Muskelly introduced the topic on Facebook’s Georgia’s Fossils Group with the question; “Where can I find Archaeocyathids?”
 
Montante soon replied “These, as best we know, are Georgia’s oldest fossils. Stromatolites in Georgia are about the same time period... mid Cambrian series two, roughly 513 million years old. Part of an ancient patch reef structure located now in the Bartow County Cartersville mining district. Shady dolomite formation.”

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Asa Kaplan led me to the 1950 publication Geology and Mineral Deposits of the Cartersville District, Georgia by Thomas Kesler (1) where the Shady Formation is described.
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In 1950 Kesler suspected 5 genera of archaeocyathids occurred in the Shady Formation, referring to them as “coral sponges”. He reported that they were the formation’s most abundant fossil and had been reviewed by J. Brooks Knight and G Arthur Cooper of the United States National Museum (Smithsonian).  Knight and Cooper reported; “An undetermined archaeocyathid, Nisusia sp., Semicircularea sp., Helcionella cf., Helcionella rugosa.”
 
 References;
1.       Geology and Mineral Deposits for the Cartesville District, Georgia; Thomas Kesler, United States Department of Interior. Geological Survey Professional Paper 224, Pag 63, 1950; pubs.usgs.gov/pp/0224/report.pdf