U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Monserrate member*
  • Modifications:
    • Named
  • AAPG geologic province:
    • Caribbean region
Publication:

Pessagno, E.A., Jr., 1960, Geology of the Ponce-Coamo area, Puerto Rico: Puerto Rico Economic Development Administration, p. 94-103., Prepared in cooperation with Princeton Univ. Dept. Geol


Summary:

Augustinillo formation named in Jacaguas group. Consists of 17,000 ft of marine sediments. Includes the Collores member to the east and the Monserrate member to the west. Interfingers with the Naranjo formation, and may interfinger with the Rio Culebrinas formation to the west.

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


Map showing publication footprint
  • Usage in publication:
    • Monserrate Formation*
  • Modifications:
    • Revised
    • Biostratigraphic dating
  • Dominant lithology:
    • Mudstone
    • Sandstone
  • AAPG geologic province:
    • Caribbean region
Publication:

Mattson, P.H., 1967, Cretaceous and lower Tertiary stratigraphy in west-central Puerto Rico, IN Contributions to stratigraphy: U.S. Geological Survey Bulletin, 1254-B, p. B1-B35.


Summary:

The Monserrate Member of the Augustinillo Formation of Pessagno (1960) is here revised as the Monserrate Formation because of its wide areal extent in west-central PR in the Adjuntas and Jayuya quadrangles. Consists of laminated gray mudstone and tuffaceous sandstone. Conformably overlies the Rio Prieto Formation or unconformably overlies Cretaceous rocks; is interlayered with overlying Anon Formation. Age is probably middle Eocene based on fossils.

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


Map showing publication footprint
  • Usage in publication:
    • Monserrate 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 Monserrate Formation occurs in southwestern Puerto Rico and consists of volcaniclastic siltstone and sandstone interbedded with tuff, subordinate conglomerate (clasts of augite andesite characteristic of the Lago Garzas Formation), calcarenite, and chert. Maximum thickness is 2000 meters. The Monserrate is of middle Eocene age.

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


Search archives

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 ([ ]).

Accessibility FOIA Privacy Policies and Notices

USA Gov U.S. Department of the Interior | U.S. Geological Survey
Supported by the National Cooperative Geologic Mapping Program
Page Contact Information: Personnel
Page Last Modified: Thu 04 Apr 2024 03:26:37 PM MDT