Ponce Limestone

The Ponce Limestone is a geologic formation in Puerto Rico. It preserves fossils dating back to the Neogene period[3] (20.45 million years ago (Mya).

Ponce Limestone Stratigraphic range: Neogene ~23.03–2.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Ponce Limestone, near Río Pastillo, Bo. Canas, Ponce, Puerto Rico, looking southwest from INT PR-163 and PR-500
Type	Formation
Lithology
Primary	Limestone
Other	Carbonate,[1] Clastic facies,[2] Chalk, Marl, Shale Phosphate
Location
Coordinates	18.007°N 66.661°W
Approximate paleocoordinates	18.0°N 66.6°W
Region	Caribbean
Country	Puerto Rico
Type section
Named for	Ponce, Puerto Rico
Named by	Watson H. Monroe
Ponce Limestone (Puerto Rico)

Description

Ponce Limestone includes beds of brown clay and has a maximum estimated thickness of 850 meters.[4] It consists mostly of yellowish-orange, soft to moderately hard, fossiliferous limestone and appears almost continuously as a narrow band extending from Bahía Montalva in Patillas to Río Pastillo, in Barrio Canas.[5]

Deposits

Exposed in the Ponce, Río Descalabrado, Punta Cucharas, Yauco, Punta Verraco, Guanica, La Parguera, San German, and Cabo Rojo quadrangles of the United States Geological Survey maps.[6]

Fossil content

Various fossils have been found in the Ponce Limestone: molds of gastropods, pelecypods, coral heads, and large foraminifera are indicative of deposition in shallow-water lagoon and back-reef environments. The large foraminifera, Lepidocyclina undosa and the ahermatypic “deep sea” coral Flabellum are reported within the Ponce Limestone.[7]

See also

• List of fossiliferous stratigraphic units in Puerto Rico
• Caliche

References

1. Geology and Hydrogeology of the Caribbean Islands Aquifer System of the Commonwealth of Puerto Rico and the U.S. Virgin Islands: Regional Aquifer-System Analysis. ROBERT A. RENKEN, W.C. WARD, I.P. GILL, FERNANDO GÓMEZ-GÓMEZ, JESÚS RODRÍGUEZ-MARTÍNEZ, et. al. USGS. Professional Paper 1419. Reston, Virginia. 2002. p. 17. Accessed 13 November 2019.]
2. Geology and Hydrogeology of the Caribbean Islands Aquifer System of the Commonwealth of Puerto Rico and the U.S. Virgin Islands. Robert Renken, et. al. United States Department of the Interior. US Geological Survey. Professional Paper 1419. 2002. p. 17. Retrieved 14 November 2019. p. 17.]
3. Fossilworks: Gateway to the Paleobiology Database. Archived 2014-07-31 at the Wayback Machine Various Contributors. The Paleobiology Database. Retrieved 8 July 2014.
4. Ponce Limestone. USGS. "Mineral Resources On-Line Spatial Data". Retrieved 6 August 2014.
5. Geology and Hydrogeology of the Caribbean Islands Aquifer System of the Commonwealth of Puerto Rico and the U.S. Virgin Islands. Robert A. Renken, W.C. Ward, I.P. Gill, Fernando Gomez-Gomez, Jesus Rodriguez-Martinez, et. al. USGS. Professional Paper 1419. Reston, Virginia. 2002. p. 20. Accessed 13 November 2019.]
6. Ponce Limestone. USGS. "Mineral Resources On-Line Spatial Data". Retrieved 6 August 2014.
7. Geology and Hydrogeology of the Caribbean Islands Aquifer System of the Commonwealth of Puerto Rico and the U.S. Virgin Islands. Renken, Robert, et. al. U.S. geological Survey. Professional Paper 1419. Reston, Virginia. 2002. p. 20. Accessed 14 November 2019.]

External links

• Geology and Hydrogeology of the Caribbean Islands Aquifer System of the Commonwealth of Puerto Rico and the U.S. Virgin Islands: Regional Aquifer-System Analysis. ROBERT A. RENKEN, W.C. WARD, I.P. GILL, FERNANDO GÓMEZ-GÓMEZ, JESÚS RODRÍGUEZ-MARTÍNEZ, et. al. USGS. Professional Paper 1419. Reston, Virginia. 2002. Accessed 13 November 2019.
• Geologia del Distrito Ponce. G. J. Mitchell. Revista de Obras Publicas de Puerto Rico. Year VII. Issue 1. January 1930. Pages 7-9. Accessed 1 August 2020.

Further reading

• Monroe, W.H., 1972, Geology of the middle Tertiary rocks in the Ponce-Guanica area—a progress report: U.S. Geological Survey Open-File Report 72-258, Washington, D.C., scale 1:20,000.
• USGS Pub ofr72258.
• Volckmann, R.P., 1984a, Geologic map of the Cabo Rojo and Parguera quadrangles, southwest Puerto Rico: U.S. Geological Survey Miscellaneous Investigations Series Map I-1557, scale 1:20,000.
• USGS Pub i1557.
• Volckmann, R.P., 1984b, Geologic map of the Puerto Real quadrangle, southwest Puerto Rico: U.S. Geological Survey Miscellaneous Investigations Series Map I-1559, scale 1:20,000.
• USGS Pub i1559.
• Krushensky and Monroe, 1975
• Krushensky and Monroe, 1978
• Krushensky and Monroe, 1979
• Mattson and Glover, 1973
• Monroe, W.H., 1973b