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 / 18.007; -66.661
Approximate paleocoordinates	18.0°N 66.6°W / 18.0; -66.6
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

• Paleontology portal
• Puerto Rico portal

• List of fossiliferous stratigraphic units in Puerto Rico
• Caliche