Usage:
Rio Abajo Formation (PR*)
Geologic age:
Early Cretaceous(?)*
Type section, locality, area and/or origin of name:
Type area: exposures in roadcuts and quarry along Highway 942, between 37,500 N. and 217,900 E.; 38,200 N. (Puerto Rico Meter Grid System), and in small borrow pit along Route 3 (Puerto Rico Meter Grid System 222,300 E.; 35,500 N.), near Rio Abajo, Humacao quadrangle, east-central Puerto Rico (M'Gonigle, 1977).
AAPG geologic province:
Caribbean region*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).