Hawthorn Group

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Hawthorn Group
Stratigraphic range: Miocene
Type Geological formation
Sub-units (See text)
Underlies Ocala Limestone
Thickness > 330 feet
Location
Region North Florida
Country  United States
Type section
Named for Hawthorne, Florida
Named by L.C. Johnson, 1887
Location of the Hawthorn Group within Florida (in red).

The Hawthorn Group is a Late Oligocene to Pliocene grouping of several geologic formations and members in North Florida, United States.

The Hawthorn Group was originally called the Waldo Formation in 1887 by L. C. Johnson of the USGS and became Hawthorne beds for sediments being quarried and ground up as fertilizer near Hawthorne, Florida.[1]

Age[edit]

Period: Neogene
Epoch: Miocene
Faunal stage: Chattian through early Blancan ~28.4 to ~2.588 mya, calculates to a period of 25.512 million years

Location[edit]

The Hawthorn Group extends from Suwannee County in the north and southward to Hernando County. It encompasses in part the counties of Gilchrist, Levy, Dixie, Citrus, Sumter, Alachua and Marion County. The Hawthorn is also present below undifferentiated sediments (TQu) as well as the Tamiami Formation from Polk County south through Highlands, Glades, Hendry, Dade, Collier, and Monroe County at depths ranging from mean sea level near Polk to below 600 meters in Monroe Co.[2] The Hawthorn overlies Ocala Limestone[3]

Sub-units[edit]

Paleofauna[edit]

Reptiles

Birds

Mammals

References[edit]

  1. ^ Geology of Florida: Miocene to Holocene. University of Florida Geology
  2. ^ USGS Florida Geology
  3. ^ Glen L. Faulkner, Geological Survey (U.S.), United States. Army. Corps of Engineers, Geohydrology of the Cross-Florida Barge Canal area, Tallahassee, 1973.