Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China
The increase in the depth and intensity of bioturbation through the Proterozoic-Phanerozoic transition changed the substrates on which marine benthos lived from being relatively firm with a sharp sediment-water interface to having a high water content and blurry sediment-water interface. Additionall...
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ftchinacscnigpas:oai:ir.nigpas.ac.cn:332004/21881 2023-05-15T17:22:44+02:00 Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China Dornbos, SQ Bottjer, DJ Chen, JY 2004-06-01 http://ir.nigpas.ac.cn/handle/332004/21881 https://doi.org/10.1080/00241160410004764 英语 eng TAYLOR & FRANCIS AS LETHAIA http://ir.nigpas.ac.cn/handle/332004/21881 doi:10.1080/00241160410004764 Meishucun Formation Radulichnus Thalassinoides microbial mats Cambrian BIOTURBATION TRANSITION FOSSILIZATION ICHNOFABRICS NEWFOUNDLAND ORDOVICIAN DEPOSITS MOLLUSKS FOSSILS EXTENT Paleontology 期刊论文 2004 ftchinacscnigpas https://doi.org/10.1080/00241160410004764 2019-08-14T12:45:03Z The increase in the depth and intensity of bioturbation through the Proterozoic-Phanerozoic transition changed the substrates on which marine benthos lived from being relatively firm with a sharp sediment-water interface to having a high water content and blurry sediment-water interface. Additionally, microbial mats, once dominant on normal marine Proterozoic seafloors, were relegated to stressed settings lacking intense metazoan activity. This change in substrates has been termed the 'agronomic revolution', and its impact on benthic metazoans has been termed the 'Cambrian substrate revolution'. The shallow marine phosphorites of the Lower Cambrian Meishucun Formation of southwest China contain evidence suggestive of the presence of seafloor microbial mats. This evidence includes abundant and distinctive red-colored bedding planes enriched in heavy iron minerals and mica, interpreted as resulting from mat-decay mineralization and mica trapping by microbial mats. The radular grazing trace fossil Radulichnus is also found in this formation, indicating a firm, microbial mat-bound substrate. These radular scratches are always preserved with circular impressions around 10 cm in diameter, possibly the fossils of soft-bodied organisms. The first relatively intense bioturbation in this region is found in this formation and is dominated by horizontal Thalassinoides burrows, which could represent undermat mining behavior. The evidence for the presence of microbial mats in the Lower Cambrian Meishucon Formation, and for metazoan lifestyles associated with such mat-bound seafloors, reveals that normal marine environments dominated by typical Proterozoic-style soft substrates still existed during the Cambrian substrate revolution. Report Newfoundland Nanjing Institute of Geology and Palaeontology: NIGPAS OpenIR (Chinese Academy of Sciences) Burrows ENVELOPE(163.650,163.650,-74.300,-74.300) Lethaia 37 1 3 20 |
institution |
Open Polar |
collection |
Nanjing Institute of Geology and Palaeontology: NIGPAS OpenIR (Chinese Academy of Sciences) |
op_collection_id |
ftchinacscnigpas |
language |
English |
topic |
Meishucun Formation Radulichnus Thalassinoides microbial mats Cambrian BIOTURBATION TRANSITION FOSSILIZATION ICHNOFABRICS NEWFOUNDLAND ORDOVICIAN DEPOSITS MOLLUSKS FOSSILS EXTENT Paleontology |
spellingShingle |
Meishucun Formation Radulichnus Thalassinoides microbial mats Cambrian BIOTURBATION TRANSITION FOSSILIZATION ICHNOFABRICS NEWFOUNDLAND ORDOVICIAN DEPOSITS MOLLUSKS FOSSILS EXTENT Paleontology Dornbos, SQ Bottjer, DJ Chen, JY Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
topic_facet |
Meishucun Formation Radulichnus Thalassinoides microbial mats Cambrian BIOTURBATION TRANSITION FOSSILIZATION ICHNOFABRICS NEWFOUNDLAND ORDOVICIAN DEPOSITS MOLLUSKS FOSSILS EXTENT Paleontology |
description |
The increase in the depth and intensity of bioturbation through the Proterozoic-Phanerozoic transition changed the substrates on which marine benthos lived from being relatively firm with a sharp sediment-water interface to having a high water content and blurry sediment-water interface. Additionally, microbial mats, once dominant on normal marine Proterozoic seafloors, were relegated to stressed settings lacking intense metazoan activity. This change in substrates has been termed the 'agronomic revolution', and its impact on benthic metazoans has been termed the 'Cambrian substrate revolution'. The shallow marine phosphorites of the Lower Cambrian Meishucun Formation of southwest China contain evidence suggestive of the presence of seafloor microbial mats. This evidence includes abundant and distinctive red-colored bedding planes enriched in heavy iron minerals and mica, interpreted as resulting from mat-decay mineralization and mica trapping by microbial mats. The radular grazing trace fossil Radulichnus is also found in this formation, indicating a firm, microbial mat-bound substrate. These radular scratches are always preserved with circular impressions around 10 cm in diameter, possibly the fossils of soft-bodied organisms. The first relatively intense bioturbation in this region is found in this formation and is dominated by horizontal Thalassinoides burrows, which could represent undermat mining behavior. The evidence for the presence of microbial mats in the Lower Cambrian Meishucon Formation, and for metazoan lifestyles associated with such mat-bound seafloors, reveals that normal marine environments dominated by typical Proterozoic-style soft substrates still existed during the Cambrian substrate revolution. |
format |
Report |
author |
Dornbos, SQ Bottjer, DJ Chen, JY |
author_facet |
Dornbos, SQ Bottjer, DJ Chen, JY |
author_sort |
Dornbos, SQ |
title |
Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
title_short |
Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
title_full |
Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
title_fullStr |
Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
title_full_unstemmed |
Evidence for seafloor microbial mats and associated metazoan lifestyles in Lower Cambrian phosphorites of Southwest China |
title_sort |
evidence for seafloor microbial mats and associated metazoan lifestyles in lower cambrian phosphorites of southwest china |
publisher |
TAYLOR & FRANCIS AS |
publishDate |
2004 |
url |
http://ir.nigpas.ac.cn/handle/332004/21881 https://doi.org/10.1080/00241160410004764 |
long_lat |
ENVELOPE(163.650,163.650,-74.300,-74.300) |
geographic |
Burrows |
geographic_facet |
Burrows |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_relation |
LETHAIA http://ir.nigpas.ac.cn/handle/332004/21881 doi:10.1080/00241160410004764 |
op_doi |
https://doi.org/10.1080/00241160410004764 |
container_title |
Lethaia |
container_volume |
37 |
container_issue |
1 |
container_start_page |
3 |
op_container_end_page |
20 |
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1766109559420616704 |