Sierra del Álamo (EA) locality: Late/Upper Triassic, Mexico

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Chlorophyceae - Dasycladales - Triploporellaceae
Griphoporella curvata Guembel 1915
Chlorophyceae - Dasycladales - Dasycladaceae
Macroporella sp. Pia 1912
Gyroporella sp. Gümbel 1872
see common names

Geography
Country:Mexico State/province:Sonora
Coordinates: 30.7° North, 112.6° West (view map)
Paleocoordinates:11.5° North, 54.0° West
Time
Period:Triassic Epoch:Late/Upper Triassic
10 m.y. bin:Triassic 3-4
Key time interval:Late/Upper Triassic
Age range of interval:237.00000 - 201.40000 m.y. ago
Stratigraphy
Geological group:El Antimonio Formation:Rio Asunción
Stratigraphic resolution:formation
Stratigraphy comments: Late Norian from ammonoid and bivalve biostratigraphy (Damborenea & González-León 1997 and references therein; González-León 1997).
Lithology and environment
Primary lithology: lithified wackestone
Secondary lithology: lithified grainstone
Lithology description: At Sierra del Álamo, the Rio Asunción Formation (upper part of the El Antimonio group succession, ca. 109 m), consists of shallow-marine limestone, siltstones to fine grained sandstones, some intercalated volcanics, and shales. A distinct carbonate interval, dated by ammonoid and bivalve biostratigraphy as Norian in age (Damborenea & González-León 1997 and references therein; González-León 1997), contains sponge-coral biostromes with algae.
Environment:sand shoal
Geology comments: Sand sheets and sand shoals, agitated water (siliciclastic lithoclastic ostracod/rich Wackestone to Grainstone).
Taphonomy
Modes of preservation:body,original aragonite,replaced with calcite
Size of fossils:mesofossils
Collection methods and comments
Collection excludes:all macrofossils
Reason for describing collection:taxonomic analysis
Metadata
Database number:234382
Authorizer:W. Kiessling Enterer:T. Jujihara
Modifier:T. Jujihara Research group:marine invertebrate
Created:2024-04-10 10:46:03 Last modified:2024-04-10 11:04:04
Access level:the public Released:2024-04-10 10:46:03
Creative Commons license:CC BY
Reference information

Primary reference:
87972. I. I. Bucur, S. Rigaud, N. Del Piero, A. Fucelli, E. Heerwagen, C. Peybernes, G. Peyrotty, C. Verard, J. Chablais and R. Martini. 2020. Upper Triassic calcareous algae from the Panthalassa Ocean. Rivista Italiana di Paleontologia e Stratigrafia 126(2):499-540 [W. Kiessling/T. Jujihara]