The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general
Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz sand grains are integrated to provide multiple pieces of evidenc...
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ftdoajarticles:oai:doaj.org/article:6e179051a8b8485ba4b5830f688c7dcf 2023-05-15T17:43:18+02:00 The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general Molén Mats O. 2017-12-01T00:00:00Z https://doi.org/10.1515/logos-2017-0019 https://doaj.org/article/6e179051a8b8485ba4b5830f688c7dcf EN eng Sciendo https://doi.org/10.1515/logos-2017-0019 https://doaj.org/toc/2080-6574 2080-6574 doi:10.1515/logos-2017-0019 https://doaj.org/article/6e179051a8b8485ba4b5830f688c7dcf Geologos, Vol 23, Iss 3, Pp 163-181 (2017) surface microtexture debris flow diamictite tillite bigganjargga snowball earth Geology QE1-996.5 article 2017 ftdoajarticles https://doi.org/10.1515/logos-2017-0019 2022-12-31T07:15:18Z Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz sand grains are integrated to provide multiple pieces of evidence for the geological agents responsible for the origin of the diamictites. The documented sedimentary and erosional structures, formerly interpreted in a glaciogenic context (e.g., diamict structure, pavements and striations) have been reanalysed. Field and laboratory data demonstrate that, contrary to conclusions reached in many earlier studies, the diamictites and adjacent deposits did not originate from glaciogenic processes. Evidence from macrostructures may occasionally be equivocal or can be interpreted as representing reworked, glacially derived material. Evidence from surface microtextures, from outcrops which are believed to exhibit the most unequivocal signs for glaciation, display no imprint at all of glaciogenic processes, and a multicyclical origin of the deposits can be demonstrated. The geological context implies (and no geological data contradict this) an origin by gravity flows, possibly in a submarine fan environment. This reinterpretation of the diamictites in northern Norway may imply that the palaeoclimatological hypothesis of a deep frozen earth during parts of the Neoproterozoic has to be revised. Article in Journal/Newspaper Northern Norway Varangerfjord* Varangerfjorden Directory of Open Access Journals: DOAJ Articles Norway Varangerfjorden ENVELOPE(30.000,30.000,70.000,70.000) Geologos 23 3 163 181 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
surface microtexture debris flow diamictite tillite bigganjargga snowball earth Geology QE1-996.5 |
spellingShingle |
surface microtexture debris flow diamictite tillite bigganjargga snowball earth Geology QE1-996.5 Molén Mats O. The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
topic_facet |
surface microtexture debris flow diamictite tillite bigganjargga snowball earth Geology QE1-996.5 |
description |
Upper Precambrian diamictites in Varangerfjorden (northern Norway) have been examined for evidence of origin, whether glaciogenic, gravity flow or polygenetic. Studies of geomorphology, sedimentology and surface microtextures on quartz sand grains are integrated to provide multiple pieces of evidence for the geological agents responsible for the origin of the diamictites. The documented sedimentary and erosional structures, formerly interpreted in a glaciogenic context (e.g., diamict structure, pavements and striations) have been reanalysed. Field and laboratory data demonstrate that, contrary to conclusions reached in many earlier studies, the diamictites and adjacent deposits did not originate from glaciogenic processes. Evidence from macrostructures may occasionally be equivocal or can be interpreted as representing reworked, glacially derived material. Evidence from surface microtextures, from outcrops which are believed to exhibit the most unequivocal signs for glaciation, display no imprint at all of glaciogenic processes, and a multicyclical origin of the deposits can be demonstrated. The geological context implies (and no geological data contradict this) an origin by gravity flows, possibly in a submarine fan environment. This reinterpretation of the diamictites in northern Norway may imply that the palaeoclimatological hypothesis of a deep frozen earth during parts of the Neoproterozoic has to be revised. |
format |
Article in Journal/Newspaper |
author |
Molén Mats O. |
author_facet |
Molén Mats O. |
author_sort |
Molén Mats O. |
title |
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
title_short |
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
title_full |
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
title_fullStr |
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
title_full_unstemmed |
The origin of upper Precambrian diamictites, northern Norway: a case study applicable to diamictites in general |
title_sort |
origin of upper precambrian diamictites, northern norway: a case study applicable to diamictites in general |
publisher |
Sciendo |
publishDate |
2017 |
url |
https://doi.org/10.1515/logos-2017-0019 https://doaj.org/article/6e179051a8b8485ba4b5830f688c7dcf |
long_lat |
ENVELOPE(30.000,30.000,70.000,70.000) |
geographic |
Norway Varangerfjorden |
geographic_facet |
Norway Varangerfjorden |
genre |
Northern Norway Varangerfjord* Varangerfjorden |
genre_facet |
Northern Norway Varangerfjord* Varangerfjorden |
op_source |
Geologos, Vol 23, Iss 3, Pp 163-181 (2017) |
op_relation |
https://doi.org/10.1515/logos-2017-0019 https://doaj.org/toc/2080-6574 2080-6574 doi:10.1515/logos-2017-0019 https://doaj.org/article/6e179051a8b8485ba4b5830f688c7dcf |
op_doi |
https://doi.org/10.1515/logos-2017-0019 |
container_title |
Geologos |
container_volume |
23 |
container_issue |
3 |
container_start_page |
163 |
op_container_end_page |
181 |
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1766145344586907648 |