Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México

This work shows the results of facies/microfacies and paleoenvironmental analysis of the Pozo Nuevo Formation outcropping at the Cerro Salazar, nearby the Rancho Las Norias (Central Sonora, Mexico). The Pozo Nuevo Formation represents Early-Middle Ordovician deposits of a continental carbonate shelf...

Descripción completa

Guardado en:
Detalles Bibliográficos
Publicado: 2012
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10268774_v29_n2_p330_Beresi
http://hdl.handle.net/20.500.12110/paper_10268774_v29_n2_p330_Beresi
Aporte de:
id paper:paper_10268774_v29_n2_p330_Beresi
record_format dspace
spelling paper:paper_10268774_v29_n2_p330_Beresi2023-06-08T16:00:18Z Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México Central sonora Mexico Microfacies Ordovician Paleoenvironments This work shows the results of facies/microfacies and paleoenvironmental analysis of the Pozo Nuevo Formation outcropping at the Cerro Salazar, nearby the Rancho Las Norias (Central Sonora, Mexico). The Pozo Nuevo Formation represents Early-Middle Ordovician deposits of a continental carbonate shelf that developed in the southwestern tip of Laurentia. The conodonts and trilobites described from the unit indicate a late Floian-early Dapingian age. The microfacies analysis enables identifying different sub-environments within the carbonate shelf from minor to major depth: a coastal beach, represented by quartz sandstone and laminated quartzite with desiccation cracks; an inner shelf which includes a supratidal setting constituted by dolomitized wackestone and an intertidal-subtidal lagoon characterized by diffusely laminated microbialites, oncoid mudstone, pelloid packstone grading to biopelloid and bioclastic packstone containing foraminifera and ostracods; and a subtidal setting composed of grainstone and packstone with crinoids and algae (Nuia) and detritic quartz and bioclastic packstone with bryozoans. In the lagoon as well as in the subtidal platform, there are intercalated intraclastic - bioclastic packstone levels, which are interpreted as proximal stormy events. The vertical variation of facies indicates a marked trend toward shallowing. At the base of the section fine micritic sediments deposited in a quiet, low energy lagoon, whereas a deeper subtidal environment with diverse faunas was developed in the middle part. On the other hand, at the top of the succession there is an increased participation of detrital quartz with deposition of coastal quartz sandstone culminating with thick dolomite levels of a vadose environment. 2012 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10268774_v29_n2_p330_Beresi http://hdl.handle.net/20.500.12110/paper_10268774_v29_n2_p330_Beresi
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Central sonora
Mexico
Microfacies
Ordovician
Paleoenvironments
spellingShingle Central sonora
Mexico
Microfacies
Ordovician
Paleoenvironments
Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
topic_facet Central sonora
Mexico
Microfacies
Ordovician
Paleoenvironments
description This work shows the results of facies/microfacies and paleoenvironmental analysis of the Pozo Nuevo Formation outcropping at the Cerro Salazar, nearby the Rancho Las Norias (Central Sonora, Mexico). The Pozo Nuevo Formation represents Early-Middle Ordovician deposits of a continental carbonate shelf that developed in the southwestern tip of Laurentia. The conodonts and trilobites described from the unit indicate a late Floian-early Dapingian age. The microfacies analysis enables identifying different sub-environments within the carbonate shelf from minor to major depth: a coastal beach, represented by quartz sandstone and laminated quartzite with desiccation cracks; an inner shelf which includes a supratidal setting constituted by dolomitized wackestone and an intertidal-subtidal lagoon characterized by diffusely laminated microbialites, oncoid mudstone, pelloid packstone grading to biopelloid and bioclastic packstone containing foraminifera and ostracods; and a subtidal setting composed of grainstone and packstone with crinoids and algae (Nuia) and detritic quartz and bioclastic packstone with bryozoans. In the lagoon as well as in the subtidal platform, there are intercalated intraclastic - bioclastic packstone levels, which are interpreted as proximal stormy events. The vertical variation of facies indicates a marked trend toward shallowing. At the base of the section fine micritic sediments deposited in a quiet, low energy lagoon, whereas a deeper subtidal environment with diverse faunas was developed in the middle part. On the other hand, at the top of the succession there is an increased participation of detrital quartz with deposition of coastal quartz sandstone culminating with thick dolomite levels of a vadose environment.
title Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
title_short Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
title_full Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
title_fullStr Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
title_full_unstemmed Microfacies, biota y paleoambientes sedimentarios del Ordovícico temprano-medio del cerro salazar, Sonora central, México
title_sort microfacies, biota y paleoambientes sedimentarios del ordovícico temprano-medio del cerro salazar, sonora central, méxico
publishDate 2012
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10268774_v29_n2_p330_Beresi
http://hdl.handle.net/20.500.12110/paper_10268774_v29_n2_p330_Beresi
_version_ 1768546685997285376