Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway)
This project examines the role of high-latitude storms degrading a Holocene coast formed by igneous rocks composed of low-grade chromite ore and dunite that originated within the Earth’s crust near the upper mantle. Such rocks are dense and rarely exposed at the surface by tectonic events in the rec...
Published in: | Journal of Marine Science and Engineering |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
MDPI AG
2020
|
Subjects: | |
Online Access: | https://doi.org/10.3390/jmse8090644 https://doaj.org/article/066c75adaef24c0a8ef4a1a66eb1c3b4 |
id |
ftdoajarticles:oai:doaj.org/article:066c75adaef24c0a8ef4a1a66eb1c3b4 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:066c75adaef24c0a8ef4a1a66eb1c3b4 2023-05-15T17:43:23+02:00 Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) Markes E. Johnson 2020-08-01T00:00:00Z https://doi.org/10.3390/jmse8090644 https://doaj.org/article/066c75adaef24c0a8ef4a1a66eb1c3b4 EN eng MDPI AG https://www.mdpi.com/2077-1312/8/9/644 https://doaj.org/toc/2077-1312 doi:10.3390/jmse8090644 2077-1312 https://doaj.org/article/066c75adaef24c0a8ef4a1a66eb1c3b4 Journal of Marine Science and Engineering, Vol 8, Iss 644, p 644 (2020) coastal storm deposits storm surge hydrodynamic equations high-latitude settings Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 article 2020 ftdoajarticles https://doi.org/10.3390/jmse8090644 2022-12-31T12:03:21Z This project examines the role of high-latitude storms degrading a Holocene coast formed by igneous rocks composed of low-grade chromite ore and dunite that originated within the Earth’s crust near the upper mantle. Such rocks are dense and rarely exposed at the surface by tectonic events in the reconfiguration of old ocean basins. An unconsolidated boulder beach occupies Støypet valley on Leka Island in northern Norway, formerly an open channel 10,000 years ago when glacial ice was in retreat and rebound of the land surface was about to commence. Sea cliffs exposing a stratiform ore body dissected by fractures was subject to wave erosion that shed large cobbles and small boulders into the channel. Competing mathematical equations are applied to estimate the height of storm waves impacting the channel floor and cliffs, and the results are compared with observations on wave heights generated by recent storms striking the Norwegian coast with the intensity of an orkan (Norwegian for hurricane). Lateral size variations in beach clasts suggest that Holocene storms struck Leka Island from the southwest with wave heights between 5 and 7.5 m based on the largest beach boulders. This result compares favorably with recent high-latitude storm tracks in the Norwegian Sea and their recorded wave heights. The density of low-grade chromite ore (3.32 g/cm 3 ) sampled from the beach deposit exceeds that of rocks like limestone or other igneous rocks such as rhyolite, andesite, and basalt taken into consideration regarding coastal boulder deposits associated with classic hurricanes in more tropical settings. Article in Journal/Newspaper Northern Norway Norwegian Sea Directory of Open Access Journals: DOAJ Articles Norwegian Sea Norway Leka ENVELOPE(11.709,11.709,65.089,65.089) Støypet ENVELOPE(11.611,11.611,65.101,65.101) Journal of Marine Science and Engineering 8 9 644 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
coastal storm deposits storm surge hydrodynamic equations high-latitude settings Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 |
spellingShingle |
coastal storm deposits storm surge hydrodynamic equations high-latitude settings Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 Markes E. Johnson Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
topic_facet |
coastal storm deposits storm surge hydrodynamic equations high-latitude settings Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 |
description |
This project examines the role of high-latitude storms degrading a Holocene coast formed by igneous rocks composed of low-grade chromite ore and dunite that originated within the Earth’s crust near the upper mantle. Such rocks are dense and rarely exposed at the surface by tectonic events in the reconfiguration of old ocean basins. An unconsolidated boulder beach occupies Støypet valley on Leka Island in northern Norway, formerly an open channel 10,000 years ago when glacial ice was in retreat and rebound of the land surface was about to commence. Sea cliffs exposing a stratiform ore body dissected by fractures was subject to wave erosion that shed large cobbles and small boulders into the channel. Competing mathematical equations are applied to estimate the height of storm waves impacting the channel floor and cliffs, and the results are compared with observations on wave heights generated by recent storms striking the Norwegian coast with the intensity of an orkan (Norwegian for hurricane). Lateral size variations in beach clasts suggest that Holocene storms struck Leka Island from the southwest with wave heights between 5 and 7.5 m based on the largest beach boulders. This result compares favorably with recent high-latitude storm tracks in the Norwegian Sea and their recorded wave heights. The density of low-grade chromite ore (3.32 g/cm 3 ) sampled from the beach deposit exceeds that of rocks like limestone or other igneous rocks such as rhyolite, andesite, and basalt taken into consideration regarding coastal boulder deposits associated with classic hurricanes in more tropical settings. |
format |
Article in Journal/Newspaper |
author |
Markes E. Johnson |
author_facet |
Markes E. Johnson |
author_sort |
Markes E. Johnson |
title |
Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
title_short |
Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
title_full |
Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
title_fullStr |
Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
title_full_unstemmed |
Holocene Boulder Beach Eroded from Chromite and Dunite Sea Cliffs at Støypet on Leka Island (Northern Norway) |
title_sort |
holocene boulder beach eroded from chromite and dunite sea cliffs at støypet on leka island (northern norway) |
publisher |
MDPI AG |
publishDate |
2020 |
url |
https://doi.org/10.3390/jmse8090644 https://doaj.org/article/066c75adaef24c0a8ef4a1a66eb1c3b4 |
long_lat |
ENVELOPE(11.709,11.709,65.089,65.089) ENVELOPE(11.611,11.611,65.101,65.101) |
geographic |
Norwegian Sea Norway Leka Støypet |
geographic_facet |
Norwegian Sea Norway Leka Støypet |
genre |
Northern Norway Norwegian Sea |
genre_facet |
Northern Norway Norwegian Sea |
op_source |
Journal of Marine Science and Engineering, Vol 8, Iss 644, p 644 (2020) |
op_relation |
https://www.mdpi.com/2077-1312/8/9/644 https://doaj.org/toc/2077-1312 doi:10.3390/jmse8090644 2077-1312 https://doaj.org/article/066c75adaef24c0a8ef4a1a66eb1c3b4 |
op_doi |
https://doi.org/10.3390/jmse8090644 |
container_title |
Journal of Marine Science and Engineering |
container_volume |
8 |
container_issue |
9 |
container_start_page |
644 |
_version_ |
1766145452203311104 |