Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies)
The sub-meridional seaway that connected Paleo-Arctic and Paleo-Tethys basins was one of the most important geographical attributes of the Late Paleozoic Pangea landscape, paleogeography and paleoclimate. Existing models about the timing of the disconnection of the Paleo-Arctic and the Paleo-Tethyan...
Main Author: | |
---|---|
Format: | Text |
Language: | unknown |
Published: |
ScholarWorks
2018
|
Subjects: | |
Online Access: | https://scholarworks.boisestate.edu/geo_facpubs/438 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1439/viewcontent/davydov_vladimir_precaspian_isthmus_emergence_elsevier_ms.pdf |
id |
ftboisestateu:oai:scholarworks.boisestate.edu:geo_facpubs-1439 |
---|---|
record_format |
openpolar |
spelling |
ftboisestateu:oai:scholarworks.boisestate.edu:geo_facpubs-1439 2023-10-29T02:29:52+01:00 Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) Davydov, Vladimir I. 2018-12-15T08:00:00Z application/pdf https://scholarworks.boisestate.edu/geo_facpubs/438 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1439/viewcontent/davydov_vladimir_precaspian_isthmus_emergence_elsevier_ms.pdf unknown ScholarWorks https://scholarworks.boisestate.edu/geo_facpubs/438 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1439/viewcontent/davydov_vladimir_precaspian_isthmus_emergence_elsevier_ms.pdf This is an author-produced, peer-reviewed version of this article. © 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 license. The final, definitive version of this document can be found online at Palaeogeography, Palaeoclimatology, Palaeoecology , doi: 10.1016/j.palaeo.2018.09.007 http://creativecommons.org/licenses/by-nc-nd/4.0/ Geosciences Faculty Publications and Presentations oceanic gateway isthmus late Paleozoic glaciation benthic foraminifera continents configuration Earth Sciences Geophysics and Seismology text 2018 ftboisestateu 2023-09-29T15:18:24Z The sub-meridional seaway that connected Paleo-Arctic and Paleo-Tethys basins was one of the most important geographical attributes of the Late Paleozoic Pangea landscape, paleogeography and paleoclimate. Existing models about the timing of the disconnection of the Paleo-Arctic and the Paleo-Tethyan oceans is very controversial and poorly documented. Warm-water benthic foraminifera (WWBF) were utilized to establish the precise timing of the closure of the Urals-Precaspian-Paleo-Tethys Seaway (UPTS) during Cisuralian time. The WWBF of Paleo-Tethys and those of the Ural-Precaspian Basins during the Gzhelian-Asselian, display a considerably high level of similarity. Beginning from the Sakmarian, the faunas of these two regions became dissimilar, suggesting a break in the connection between the Paleo-Tethys and Ural-Precaspian Basins. The sedimentological evidence (olistostromes and seismites) of the final collision of the Eastern Ural, Kazakhstania, Scythian-Turan plates with the southeastern part of the Russian Platform during Late Paleozoic also support the emergence of the Precaspian Isthmus at the Asselian-Sakmarian transition. The oceanic currents in the Precaspian and the Southern Ural Basins before the Sakmarian were directed northward and later changed to the south. These biotic and physical changes are consistent with the proposed timing of the cutoff of the UPTS. The biotic and sedimentologic features clearly suggest the UPTS closure and the origination of Precaspian Isthmus during the Asselian-Sakmarian transition. The abrupt changes in the oceanic circulation triggered changes in atmospheric CO2, atmospheric circulation and, possibly, albedo feedback. The emergence of the Precaspian Isthmus induced an increase in the poleward salt and heat transport towards mid- to lower latitude Gondwana and Cathasia margins. The warm water currents and moisture along the margins of Gondwana caused a rapid increase in the precipitation necessary to build significant ice sheets during the early-middle Sakmarian. Text albedo Arctic Foraminifera* Paleo-Arctic Boise State University: Scholar Works |
institution |
Open Polar |
collection |
Boise State University: Scholar Works |
op_collection_id |
ftboisestateu |
language |
unknown |
topic |
oceanic gateway isthmus late Paleozoic glaciation benthic foraminifera continents configuration Earth Sciences Geophysics and Seismology |
spellingShingle |
oceanic gateway isthmus late Paleozoic glaciation benthic foraminifera continents configuration Earth Sciences Geophysics and Seismology Davydov, Vladimir I. Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
topic_facet |
oceanic gateway isthmus late Paleozoic glaciation benthic foraminifera continents configuration Earth Sciences Geophysics and Seismology |
description |
The sub-meridional seaway that connected Paleo-Arctic and Paleo-Tethys basins was one of the most important geographical attributes of the Late Paleozoic Pangea landscape, paleogeography and paleoclimate. Existing models about the timing of the disconnection of the Paleo-Arctic and the Paleo-Tethyan oceans is very controversial and poorly documented. Warm-water benthic foraminifera (WWBF) were utilized to establish the precise timing of the closure of the Urals-Precaspian-Paleo-Tethys Seaway (UPTS) during Cisuralian time. The WWBF of Paleo-Tethys and those of the Ural-Precaspian Basins during the Gzhelian-Asselian, display a considerably high level of similarity. Beginning from the Sakmarian, the faunas of these two regions became dissimilar, suggesting a break in the connection between the Paleo-Tethys and Ural-Precaspian Basins. The sedimentological evidence (olistostromes and seismites) of the final collision of the Eastern Ural, Kazakhstania, Scythian-Turan plates with the southeastern part of the Russian Platform during Late Paleozoic also support the emergence of the Precaspian Isthmus at the Asselian-Sakmarian transition. The oceanic currents in the Precaspian and the Southern Ural Basins before the Sakmarian were directed northward and later changed to the south. These biotic and physical changes are consistent with the proposed timing of the cutoff of the UPTS. The biotic and sedimentologic features clearly suggest the UPTS closure and the origination of Precaspian Isthmus during the Asselian-Sakmarian transition. The abrupt changes in the oceanic circulation triggered changes in atmospheric CO2, atmospheric circulation and, possibly, albedo feedback. The emergence of the Precaspian Isthmus induced an increase in the poleward salt and heat transport towards mid- to lower latitude Gondwana and Cathasia margins. The warm water currents and moisture along the margins of Gondwana caused a rapid increase in the precipitation necessary to build significant ice sheets during the early-middle Sakmarian. |
format |
Text |
author |
Davydov, Vladimir I. |
author_facet |
Davydov, Vladimir I. |
author_sort |
Davydov, Vladimir I. |
title |
Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
title_short |
Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
title_full |
Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
title_fullStr |
Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
title_full_unstemmed |
Precaspian Isthmus Emergence Triggered the Early Sakmarian Glaciation (Paleontologic, Sedimentologic and Geochemical Proxies) |
title_sort |
precaspian isthmus emergence triggered the early sakmarian glaciation (paleontologic, sedimentologic and geochemical proxies) |
publisher |
ScholarWorks |
publishDate |
2018 |
url |
https://scholarworks.boisestate.edu/geo_facpubs/438 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1439/viewcontent/davydov_vladimir_precaspian_isthmus_emergence_elsevier_ms.pdf |
genre |
albedo Arctic Foraminifera* Paleo-Arctic |
genre_facet |
albedo Arctic Foraminifera* Paleo-Arctic |
op_source |
Geosciences Faculty Publications and Presentations |
op_relation |
https://scholarworks.boisestate.edu/geo_facpubs/438 https://scholarworks.boisestate.edu/context/geo_facpubs/article/1439/viewcontent/davydov_vladimir_precaspian_isthmus_emergence_elsevier_ms.pdf |
op_rights |
This is an author-produced, peer-reviewed version of this article. © 2018, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 license. The final, definitive version of this document can be found online at Palaeogeography, Palaeoclimatology, Palaeoecology , doi: 10.1016/j.palaeo.2018.09.007 http://creativecommons.org/licenses/by-nc-nd/4.0/ |
_version_ |
1781052143584673792 |