- Usage in publication:
-
- Cuyon Formation*
- Modifications:
-
- Named
- Dominant lithology:
-
- Sandstone
- Volcanics
- Tuff
- Limestone
- AAPG geologic province:
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- Caribbean region
Summary:
Rocks of the Cuyon Formation, here named, were previously included in the Robles Formation of Berryhill and Glover (1960). Consists of 75 m of heterogeneous rocks divided into three subequal parts: 1) basal third is reddish- to purplish-gray poorly sorted, obscurely stratified volcaniclastic sandstone; 2) middle third is drab thin- to thick-bedded reworked tuff with lenses of volcaniclastic conglomerate; 3) upper third is bluish-gray hard, fossiliferous, thin- to thick-bedded limestone interleaved with volcanic sandstone. Limestone metamorphosed to skarn near the Cuyon stock. Unconformably overlies Robles Formation; upper contact eroded or cut out by faulting. Correlates with Miramar Formation of south-central PR and San German Formation of southwest PR. Age is Campanian to late Maastrichtian based on fossils in limestone of the upper member.
Source: GNU records (USGS DDS-6; Reston GNULEX).
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 ([ ]).