Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA
Between ~20 and 15 ka the Laurentide Ice Sheet retreated from the edge of the continental shelf, ἀrst to the Maine coast and then across Maine to the northern reaches of the Penobscot Lowland. The Lowland, being isostatically depressed, was inundated by the sea. As ice then retreated into Maine’s we...
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ftuninewbrunojs:oai:ojs.journals.lib.unb.ca:article/25439 2023-05-15T16:41:03+02:00 Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA Hooke, Roger LeBaron Hanson, Paul R. 2017-10-02 text/html application/pdf https://journals.lib.unb.ca/index.php/ag/article/view/25439 eng eng Atlantic Geoscience Society https://journals.lib.unb.ca/index.php/ag/article/view/25439/30002 https://journals.lib.unb.ca/index.php/ag/article/view/25439/29982 https://journals.lib.unb.ca/index.php/ag/article/view/25439 Copyright (c) 2017 Atlantic Geology Atlantic Geoscience; Vol. 53 (2017); 285 - 300 2564-2987 Maine Penobscot River Deltas Eskers Late glacial info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion research-article 2017 ftuninewbrunojs 2022-07-11T11:42:13Z Between ~20 and 15 ka the Laurentide Ice Sheet retreated from the edge of the continental shelf, ἀrst to the Maine coast and then across Maine to the northern reaches of the Penobscot Lowland. The Lowland, being isostatically depressed, was inundated by the sea. As ice then retreated into Maine’s western mountains, valleys through the mountains became estuaries. In the estuary now occupied by the Penobscot River’s East Branch, ten ice-marginal deltas were built during pauses in this part of the retreat. By 14 ka the ice had retreated far enough to expose land in the valley bottom between the ice front and the sea, and the Penobscot River was (re)born. This occurred near the present conᴀuence of the Seboeis River and the East Branch. The river gradually extended itself northward as the ice retreated and southward as relative sea level fell. Braidplains were formed and incised, leaving terraces. High initial discharges eroded the eastern ᴀanks of the esker and deltas, redepositing silt, sand, and gravel all the way to the present head of Penobscot Bay. By ~10 ka the discharge had decreased, the river was adjusting to on-going differential isostatic rebound, and finer sediment was accumulating, forming the present floodplain. Article in Journal/Newspaper Ice Sheet University of New Brunswick: Centre for Digital Scholarship Journals Atlantic Geology 53 285 300 |
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Open Polar |
collection |
University of New Brunswick: Centre for Digital Scholarship Journals |
op_collection_id |
ftuninewbrunojs |
language |
English |
topic |
Maine Penobscot River Deltas Eskers Late glacial |
spellingShingle |
Maine Penobscot River Deltas Eskers Late glacial Hooke, Roger LeBaron Hanson, Paul R. Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
topic_facet |
Maine Penobscot River Deltas Eskers Late glacial |
description |
Between ~20 and 15 ka the Laurentide Ice Sheet retreated from the edge of the continental shelf, ἀrst to the Maine coast and then across Maine to the northern reaches of the Penobscot Lowland. The Lowland, being isostatically depressed, was inundated by the sea. As ice then retreated into Maine’s western mountains, valleys through the mountains became estuaries. In the estuary now occupied by the Penobscot River’s East Branch, ten ice-marginal deltas were built during pauses in this part of the retreat. By 14 ka the ice had retreated far enough to expose land in the valley bottom between the ice front and the sea, and the Penobscot River was (re)born. This occurred near the present conᴀuence of the Seboeis River and the East Branch. The river gradually extended itself northward as the ice retreated and southward as relative sea level fell. Braidplains were formed and incised, leaving terraces. High initial discharges eroded the eastern ᴀanks of the esker and deltas, redepositing silt, sand, and gravel all the way to the present head of Penobscot Bay. By ~10 ka the discharge had decreased, the river was adjusting to on-going differential isostatic rebound, and finer sediment was accumulating, forming the present floodplain. |
format |
Article in Journal/Newspaper |
author |
Hooke, Roger LeBaron Hanson, Paul R. |
author_facet |
Hooke, Roger LeBaron Hanson, Paul R. |
author_sort |
Hooke, Roger LeBaron |
title |
Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
title_short |
Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
title_full |
Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
title_fullStr |
Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
title_full_unstemmed |
Late- and Post-glacial history of the East Branch of the Penobscot River, Maine, USA |
title_sort |
late- and post-glacial history of the east branch of the penobscot river, maine, usa |
publisher |
Atlantic Geoscience Society |
publishDate |
2017 |
url |
https://journals.lib.unb.ca/index.php/ag/article/view/25439 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Atlantic Geoscience; Vol. 53 (2017); 285 - 300 2564-2987 |
op_relation |
https://journals.lib.unb.ca/index.php/ag/article/view/25439/30002 https://journals.lib.unb.ca/index.php/ag/article/view/25439/29982 https://journals.lib.unb.ca/index.php/ag/article/view/25439 |
op_rights |
Copyright (c) 2017 Atlantic Geology |
container_title |
Atlantic Geology |
container_volume |
53 |
container_start_page |
285 |
op_container_end_page |
300 |
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1766031484962996224 |