Home Archived October 29, 2018

South Florida Information Access (SOFIA)

publications > paper > new Tertiary stratigraphy for the Florida Keys and southern peninsula of Florida

New Tertiary stratigraphy for the Florida Keys and southern peninsula of Florida

Kevin J. Cunningham *, Donald F. McNeill and Laura A. Guertin - University of Miami, Rosenstiel School of Marine and Atmospheric Science, Division of Marine Geology and Geophysics, Miami, Florida 33149

Paul F. Ciesielski - University of Florida, Department of Geology, Gainesville, Florida 32611

Thomas M. Scott - Florida Geological Survey, 903 West Tennessee Street, Tallahassee, Florida 32304

Laurent de Verteuil - Petrotrin, Geological Services Laboratory, Pointe-a-Pierre, Trinidad, West Indies

Posted with permission. Geological Society of America Bulletin, vol. 110, no. 2, pp. 231-258, February 1998. Copyright ©1998, The Geological Society of America, Inc. (GSA). All rights reserved.
Copyright not claimed on content prepared wholly by U.S. government employees within scope of their employment. Individual scientists are hereby granted permission, without fees or further requests to GSA, to use a single figure, a single table, and/or a brief paragraph of text in other subsequent works and to make unlimited copies for noncommercial use in classrooms to further education and science. For any other use, contact Copyright Permissions, GSA, P.O. Box 9140, Boulder, CO 80301-9140, USA, fax 303-357-1073, editing@geosociety.org. Reference GSA Bulletin, ISSN 0016-7606. GSA provides this and other forums for the presentation of diverse opinions and positions by scientists worldwide, regardless of their race, citizenship, gender, religion, or political viewpoint. Opinions presented in this publication do not reflect official positions of the Society.

Note: Paper is available from the GSA Bulletin website (journal subscription is required to view full article)


Oligocene-Pleistocene Stratigraphy
Char. of the Suwannee Limestone
Char. of the Arcadia Formation
Char. of the Peace River Formation
Char. of the Long Key Formation
Char. of the Stock Island Formation
Distr. of Long Key & Stock Island Formation
Seven lithologic formations, ranging in age from Oligocene to Pleistocene, were recently penetrated by core holes in southernmost Florida. From bottom to top, they are the early Oligocene Suwannee Limestone; late-early Oligocene-to-Miocene Arcadia Formation, basal Hawthorn Group; late Miocene Peace River Formation, upper Hawthorn Group; newly proposed late Miocene-to-Pliocene Long Key and Stock Island Formations; and Pleistocene Key Largo and Miami Limestones. The rocks of the Suwannee Limestone form a third-order sequence. Although the entire thickness was not penetrated, 96 m of Suwannee core from one well contains at least 50 vertically stacked, exposure-capped limestone cycles, presumably related to rapid eustatic fluctuations while experiencing tropical to subtropical conditions. The Arcadia Formation is a composite sequence containing four high-frequency sequences composed of multiple vertically stacked carbonate cycles. Most cycles do not show evidence of subaerial exposure and were deposited under more temperate conditions, relative to the Suwannee Limestone. The Arcadia Formation in southernmost Florida is bounded by regional unconformities representing third-order sequence boundaries. Post-Arcadia transgression produced a major backstepping of sediment accumulation above the upper sequence boundary of the Arcadia Formation. The Peace River Formation, composed of diatomaceous mudstones, has been identified only beneath the Florida peninsula and is not present beneath the Florida Keys. Deposition occurred during marine transgressive to high-stand conditions and a local phosphatization event (recorded in northeast Florida). The transgression is possibly related to a global rise in sea level, which resulted in upwelling of relatively cooler, relatively nutrient-rich water masses onto the Florida Platform.

It is proposed that the absence of Peace River sediments beneath the Keys is due to sediment bypass of the upper surface of the Arcadia, a result of sediment sweeping by an ancestral Florida current. During late Miocene to Pliocene time in the Florida Keys, siliciclastics of the Long Key Formation and fine-grained carbonates of the Stock Island Formation prograded toward the southern edge of the Florida Platform and downlapped onto the regional unconformity at the top of the Arcadia. Shallow-marine Pleistocene limestones (Key Largo and Miami Limestones), deposited during tropical to subtropical conditions, drape over accretionary successions of the Long Key and Stock Island Formations.

*e-mail: kcunningham@rsmas.miami.edu

Introduction >

| Disclaimer | Privacy Statement | Accessibility |

U.S. Department of the Interior, U.S. Geological Survey
This page is: http://sofia.usgs.gov/publications/papers/new_tert_strat/index.html
Comments and suggestions? Contact: Heather Henkel - Webmaster
Last updated: 04 September, 2013 @ 02:04 PM(TJE)