Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina
Foraminiferal fossil assemblages of the shelly concentration, which represents the type section of Cerro de la Gloria Member of Las Escobas Formation, were analyzed for the first time. Taxonomic, quantitative and taphonomical analyses were made in order to obtain paleoenvironmental (physical as well...
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2003
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00166995_v36_n5_p559_Laprida http://hdl.handle.net/20.500.12110/paper_00166995_v36_n5_p559_Laprida |
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paper:paper_00166995_v36_n5_p559_Laprida2023-06-08T14:38:42Z Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina Forminifers Holocene Shallow marine paleoenvironment Shelly concentration Taphonomy beach benthic foraminifera Holocene paleoecology paleoenvironment shoreline taphonomy taxonomy Argentina Salado Basin Foraminifera Foraminiferal fossil assemblages of the shelly concentration, which represents the type section of Cerro de la Gloria Member of Las Escobas Formation, were analyzed for the first time. Taxonomic, quantitative and taphonomical analyses were made in order to obtain paleoenvironmental (physical as well biological) information. The complexity of the internal structure of the taphocoenoses was analyzed to infer the history of the final concentration process. The shell bed of Channel 15 corresponds to a shoreface longshore bar deposited in a brackish, unstable, wave-dominate coast. Shoreface and beach (foreshore) regressive facies were recognized. Taphonomic processes have modified the paleobiocoenoses by the selective preservation of autochthonous elements and by the addition of parautochthonous fauna from relict beachs and lagoons. Thus, the taphocoenoses is a within-habitat time-averaged assemblage composed of species that inhabit shallow shelf marine environments. Discrimination of autochthonous and parautochthonous fauna was possible based on taphonomic signatures of tests. The addition of the parautochthonous elements was related with longshore currents and littoral drift, and with high-energy events, probably with storm-waves, when erosion of the Pre-Mid Holocene substrate was more intense. Thus, the contribution of parautochthonous fauna is directly related with lithology and therefore, with dynamic of the paleoenvironment: in the shoreface, autochthonous fauna dominates in clastic sands with lamination and parallel stratification, whereas parautochthonous elements dominate in shoreface shelly gravels and in the foreshore sands. In the upper part of the section (beach facies), mainly parautochthonous elements related with erosion of the Pre-Mid Holocene substrate was recognized, since the shoreface was only periodically affected by marine processes, i.e., during storms. © 2003 Éditions scientifiques et médicales Elsevier SAS. All rights reserved. 2003 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00166995_v36_n5_p559_Laprida http://hdl.handle.net/20.500.12110/paper_00166995_v36_n5_p559_Laprida |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Forminifers Holocene Shallow marine paleoenvironment Shelly concentration Taphonomy beach benthic foraminifera Holocene paleoecology paleoenvironment shoreline taphonomy taxonomy Argentina Salado Basin Foraminifera |
| spellingShingle |
Forminifers Holocene Shallow marine paleoenvironment Shelly concentration Taphonomy beach benthic foraminifera Holocene paleoecology paleoenvironment shoreline taphonomy taxonomy Argentina Salado Basin Foraminifera Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| topic_facet |
Forminifers Holocene Shallow marine paleoenvironment Shelly concentration Taphonomy beach benthic foraminifera Holocene paleoecology paleoenvironment shoreline taphonomy taxonomy Argentina Salado Basin Foraminifera |
| description |
Foraminiferal fossil assemblages of the shelly concentration, which represents the type section of Cerro de la Gloria Member of Las Escobas Formation, were analyzed for the first time. Taxonomic, quantitative and taphonomical analyses were made in order to obtain paleoenvironmental (physical as well biological) information. The complexity of the internal structure of the taphocoenoses was analyzed to infer the history of the final concentration process. The shell bed of Channel 15 corresponds to a shoreface longshore bar deposited in a brackish, unstable, wave-dominate coast. Shoreface and beach (foreshore) regressive facies were recognized. Taphonomic processes have modified the paleobiocoenoses by the selective preservation of autochthonous elements and by the addition of parautochthonous fauna from relict beachs and lagoons. Thus, the taphocoenoses is a within-habitat time-averaged assemblage composed of species that inhabit shallow shelf marine environments. Discrimination of autochthonous and parautochthonous fauna was possible based on taphonomic signatures of tests. The addition of the parautochthonous elements was related with longshore currents and littoral drift, and with high-energy events, probably with storm-waves, when erosion of the Pre-Mid Holocene substrate was more intense. Thus, the contribution of parautochthonous fauna is directly related with lithology and therefore, with dynamic of the paleoenvironment: in the shoreface, autochthonous fauna dominates in clastic sands with lamination and parallel stratification, whereas parautochthonous elements dominate in shoreface shelly gravels and in the foreshore sands. In the upper part of the section (beach facies), mainly parautochthonous elements related with erosion of the Pre-Mid Holocene substrate was recognized, since the shoreface was only periodically affected by marine processes, i.e., during storms. © 2003 Éditions scientifiques et médicales Elsevier SAS. All rights reserved. |
| title |
Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| title_short |
Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| title_full |
Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| title_fullStr |
Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| title_full_unstemmed |
Benthic foraminifers and paleoecology of a Holocene shelly concentration, Salado Basin, Argentina |
| title_sort |
benthic foraminifers and paleoecology of a holocene shelly concentration, salado basin, argentina |
| publishDate |
2003 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00166995_v36_n5_p559_Laprida http://hdl.handle.net/20.500.12110/paper_00166995_v36_n5_p559_Laprida |
| _version_ |
1768545536257818624 |