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Map showing publication footprint
  • Usage in publication:
    • Los Negros Formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Caribbean region
Publication:

Nelson, A.E., 1966, Cretaceous and Tertiary rocks in the Corozal quadrangle, northern Puerto Rico, IN Contributions to stratigraphy, 1966: U.S. Geological Survey Bulletin, 1244-C, p. C9-C10.


Summary:

Rio Orocovis Formation redefined Rio Orocovis Group and Los Negros Member redefined Los Negros Formation. Conformably overlies the Avispa Formation; top unit of the Rio Orocovis.

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Los Negros Formation*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Caribbean region
Publication:

Krushensky, R.K., 2001, Geologic map of Puerto Rico with correlation chart and map unit descriptions, IN Bawiec, W.J., and others, Geology, geochemistry, geophysics, mineral ccurrences, and mineral resource assessment for the Commonwealth of Puerto Rico: U.S. Geological Survey Open-File Report, OF-98-38, scale 1:100,000


Summary:

The Los Negros Formation occurs in central Puerto Rico and consists of basaltic hyaloclastite-breccia with stringers of pillowed basaltic lava, subordinate volcanic sandstone, and minor siltstone. Maximum estimated thickness is 1800 meters. The Los Negros is of Early(?) Cretaceous age.

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 ([ ]).

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