Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions

The Main Karoo Basin of South Africa is renowned for its exceptional palaeontological record and while its vertebrate fossils have been extensively researched, Karoo floras have received considerably less attention. Poor yields of palynomorphs from the Beaufort and “Stormberg” groups have complicate...

Full description

Bibliographic Details
Main Author: Barbolini, Natasha
Format: Thesis
Language:English
Published: 2014
Subjects:
Online Access:http://hdl.handle.net10539/14776
id ftunivwitwaters:oai:wiredspace.wits.ac.za:10539/14776
record_format openpolar
spelling ftunivwitwaters:oai:wiredspace.wits.ac.za:10539/14776 2023-05-15T13:58:45+02:00 Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions Barbolini, Natasha 2014-06-12 application/pdf http://hdl.handle.net10539/14776 en eng http://hdl.handle.net10539/14776 Paleontology Paleontology - South Africa - Karoo Basin Fossils Gondwana (Geology) Thesis 2014 ftunivwitwaters 2019-08-12T15:35:49Z The Main Karoo Basin of South Africa is renowned for its exceptional palaeontological record and while its vertebrate fossils have been extensively researched, Karoo floras have received considerably less attention. Poor yields of palynomorphs from the Beaufort and “Stormberg” groups have complicated the task of erecting a comprehensive palynozonation scheme for the Karoo Supergroup. For this study, 65 palynologically productive samples from the Dwyka, Ecca, Beaufort and “Stormberg” groups allowed for systematic descriptions of all palynomorphs, as well as the ranges of the different taxa through the entire Karoo stratigraphic succession. Taxa with restricted ranges are useful for biostratigraphic correlation and these palynomorphs were used to delineate microfloral zones for the Karoo basin. The Dwyka Group contains high numbers of acritarchs and is generally low in species diversity. Useful biostratigraphic taxa for the Ecca Group include Cannanoropollis, Hamiapollenites, Platysaccus and Striatopodocarpites. Aratrisporites is a marker for the Latest Permian / Early Triassic Beaufort Group, while Cyathidites, Dictyophyllidites, Equisetosporites and Uvaesporites are indicators of the Late Triassic / Early Jurassic “Stormberg” Group. Palynostratigraphic zones correlate largely with the Karoo vertebrate biozones and severe and sudden extinction events are recognised among Karoo palynomorphs in the upper Tapinocephalus and Dicynodon assemblage zones. The first comprehensive palynological biozonation scheme for the Main Karoo Basin is proposed and the study provides a broad overview of Gondwanan Carboniferous - Jurassic floras. This study demonstrates that palynology is useful in correlating age equivalent lithostratigraphic units in the proximal and distal sectors of the Karoo Basin. Microfloras from previous South African studies are integrated within the proposed palynostratigraphic scheme, and palynological signatures of the various Karoo formations are shown to be consistent. Despite the constraints of floral provincialism, South African microfloras can be correlated to selected Gondwanan biozonations from Australia, Africa, Antarctica, New Zealand and South America. Future studies should focus on sampling more intensively over smaller stratigraphic intervals, which will assist in the correlation of time equivalent lithostratigraphic units in the different sectors of the basin, thus aiding in refinement of basin development models. Key words: palynology, Karoo, vertebrate biozones, stratigraphy, Gondwana Thesis Antarc* Antarctica Antarctica New Zealand University of the Witwatersrand, Johannesburg: WITS Institutional Repository on DSpace (WIReDSpace) New Zealand
institution Open Polar
collection University of the Witwatersrand, Johannesburg: WITS Institutional Repository on DSpace (WIReDSpace)
op_collection_id ftunivwitwaters
language English
topic Paleontology
Paleontology - South Africa - Karoo Basin
Fossils
Gondwana (Geology)
spellingShingle Paleontology
Paleontology - South Africa - Karoo Basin
Fossils
Gondwana (Geology)
Barbolini, Natasha
Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
topic_facet Paleontology
Paleontology - South Africa - Karoo Basin
Fossils
Gondwana (Geology)
description The Main Karoo Basin of South Africa is renowned for its exceptional palaeontological record and while its vertebrate fossils have been extensively researched, Karoo floras have received considerably less attention. Poor yields of palynomorphs from the Beaufort and “Stormberg” groups have complicated the task of erecting a comprehensive palynozonation scheme for the Karoo Supergroup. For this study, 65 palynologically productive samples from the Dwyka, Ecca, Beaufort and “Stormberg” groups allowed for systematic descriptions of all palynomorphs, as well as the ranges of the different taxa through the entire Karoo stratigraphic succession. Taxa with restricted ranges are useful for biostratigraphic correlation and these palynomorphs were used to delineate microfloral zones for the Karoo basin. The Dwyka Group contains high numbers of acritarchs and is generally low in species diversity. Useful biostratigraphic taxa for the Ecca Group include Cannanoropollis, Hamiapollenites, Platysaccus and Striatopodocarpites. Aratrisporites is a marker for the Latest Permian / Early Triassic Beaufort Group, while Cyathidites, Dictyophyllidites, Equisetosporites and Uvaesporites are indicators of the Late Triassic / Early Jurassic “Stormberg” Group. Palynostratigraphic zones correlate largely with the Karoo vertebrate biozones and severe and sudden extinction events are recognised among Karoo palynomorphs in the upper Tapinocephalus and Dicynodon assemblage zones. The first comprehensive palynological biozonation scheme for the Main Karoo Basin is proposed and the study provides a broad overview of Gondwanan Carboniferous - Jurassic floras. This study demonstrates that palynology is useful in correlating age equivalent lithostratigraphic units in the proximal and distal sectors of the Karoo Basin. Microfloras from previous South African studies are integrated within the proposed palynostratigraphic scheme, and palynological signatures of the various Karoo formations are shown to be consistent. Despite the constraints of floral provincialism, South African microfloras can be correlated to selected Gondwanan biozonations from Australia, Africa, Antarctica, New Zealand and South America. Future studies should focus on sampling more intensively over smaller stratigraphic intervals, which will assist in the correlation of time equivalent lithostratigraphic units in the different sectors of the basin, thus aiding in refinement of basin development models. Key words: palynology, Karoo, vertebrate biozones, stratigraphy, Gondwana
format Thesis
author Barbolini, Natasha
author_facet Barbolini, Natasha
author_sort Barbolini, Natasha
title Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
title_short Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
title_full Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
title_fullStr Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
title_full_unstemmed Palynostratigraphy of the South African Karoo supergroup and correlations with coeval Gondwanan successions
title_sort palynostratigraphy of the south african karoo supergroup and correlations with coeval gondwanan successions
publishDate 2014
url http://hdl.handle.net10539/14776
geographic New Zealand
geographic_facet New Zealand
genre Antarc*
Antarctica
Antarctica New Zealand
genre_facet Antarc*
Antarctica
Antarctica New Zealand
op_relation http://hdl.handle.net10539/14776
_version_ 1766267085960249344