Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska
Dissertation (Ph.D.) University of Alaska Fairbanks, 2007 The Late Cretaceous Matanuska Formation contains shallow and deep marine sediments and nonmarine sediment derived from the Talkeetna volcanic island arc. The sediment accumulated in the Matanuska Seaway, a tectonically active basin on the sou...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/8942 2023-05-15T15:16:37+02:00 Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska Reid, Sabra Louise Fowell, Sarah J. 2007 http://hdl.handle.net/11122/8942 unknown http://hdl.handle.net/11122/8942 Department of Geology and Geophysics Geology Paleontology Dissertation phd 2007 ftunivalaska 2023-02-23T21:37:09Z Dissertation (Ph.D.) University of Alaska Fairbanks, 2007 The Late Cretaceous Matanuska Formation contains shallow and deep marine sediments and nonmarine sediment derived from the Talkeetna volcanic island arc. The sediment accumulated in the Matanuska Seaway, a tectonically active basin on the southern margin of southcentral Alaska. The Matanuska Seaway was contemporaneous with the Cretaceous Western Interior Seaway (CWIS) of North America. Angiosperm pollen taxa from the CWIS have been used to date units and reconstruct both paleolatitude and paleoclimate (Nichols and Sweet, 1993). Comparison of pollen taxa from the CWIS to assemblages from the Matanuska Formation reveals that outcrops at Mazuma Creek, Granite Creek, Syncline Mountain, and Slide Mountain are Late Maastrichtian, while Hicks Creek outcrops are Campanian. During the Late Maastrichtian, the Matanuska Seaway was located south of 75° N latitude. The presence of ash layers overlain by low-diversity palynofloras with relatively high proportions of spores indicates the presence of volcanic recovery floras within the Matanuska Formation. Palynofloral composition and diversity of the climax vegetation suggest that the Matanuska paleoflora is a northern, transitional, continental margin flora that shares taxa with Late Cretaceous Pacific Rim floras of the Russian Far East and Japan and continental margin floras of western North America. When combined with coeval assemblages from the Alaska Peninsula, southcentral Alaskan palynofloras of the Late Cretaceous contain the most diverse assemblages of Aquilapollenites group taxa known from the North Pacific Rim. The Matanuska Seaway thus represents a coastal dispersal corridor where floras of the North Pacific Rim and western North American mingled. Within Alaska, the diversity of Late Cretaceous Aquilapollenites group taxa increases from north to south. Comparison of the Matanuska Formation palynoflora with assemblages from the interior Lower Cantwell Formation and the Arctic Prince Creek Formation reveals ... Doctoral or Postdoctoral Thesis Arctic Alaska University of Alaska: ScholarWorks@UA Arctic Fairbanks Hicks ENVELOPE(64.763,64.763,-71.144,-71.144) Pacific Prince Creek ENVELOPE(-38.067,-38.067,-54.017,-54.017) |
institution |
Open Polar |
collection |
University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
unknown |
topic |
Geology Paleontology |
spellingShingle |
Geology Paleontology Reid, Sabra Louise Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
topic_facet |
Geology Paleontology |
description |
Dissertation (Ph.D.) University of Alaska Fairbanks, 2007 The Late Cretaceous Matanuska Formation contains shallow and deep marine sediments and nonmarine sediment derived from the Talkeetna volcanic island arc. The sediment accumulated in the Matanuska Seaway, a tectonically active basin on the southern margin of southcentral Alaska. The Matanuska Seaway was contemporaneous with the Cretaceous Western Interior Seaway (CWIS) of North America. Angiosperm pollen taxa from the CWIS have been used to date units and reconstruct both paleolatitude and paleoclimate (Nichols and Sweet, 1993). Comparison of pollen taxa from the CWIS to assemblages from the Matanuska Formation reveals that outcrops at Mazuma Creek, Granite Creek, Syncline Mountain, and Slide Mountain are Late Maastrichtian, while Hicks Creek outcrops are Campanian. During the Late Maastrichtian, the Matanuska Seaway was located south of 75° N latitude. The presence of ash layers overlain by low-diversity palynofloras with relatively high proportions of spores indicates the presence of volcanic recovery floras within the Matanuska Formation. Palynofloral composition and diversity of the climax vegetation suggest that the Matanuska paleoflora is a northern, transitional, continental margin flora that shares taxa with Late Cretaceous Pacific Rim floras of the Russian Far East and Japan and continental margin floras of western North America. When combined with coeval assemblages from the Alaska Peninsula, southcentral Alaskan palynofloras of the Late Cretaceous contain the most diverse assemblages of Aquilapollenites group taxa known from the North Pacific Rim. The Matanuska Seaway thus represents a coastal dispersal corridor where floras of the North Pacific Rim and western North American mingled. Within Alaska, the diversity of Late Cretaceous Aquilapollenites group taxa increases from north to south. Comparison of the Matanuska Formation palynoflora with assemblages from the interior Lower Cantwell Formation and the Arctic Prince Creek Formation reveals ... |
author2 |
Fowell, Sarah J. |
format |
Doctoral or Postdoctoral Thesis |
author |
Reid, Sabra Louise |
author_facet |
Reid, Sabra Louise |
author_sort |
Reid, Sabra Louise |
title |
Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
title_short |
Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
title_full |
Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
title_fullStr |
Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
title_full_unstemmed |
Evidence For A Northern Transitional Continental Margin Flora In The Cretaceous (Campanian To Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska |
title_sort |
evidence for a northern transitional continental margin flora in the cretaceous (campanian to maastrichtian) matanuska formation, talkeetna mountains, southcentral alaska |
publishDate |
2007 |
url |
http://hdl.handle.net/11122/8942 |
long_lat |
ENVELOPE(64.763,64.763,-71.144,-71.144) ENVELOPE(-38.067,-38.067,-54.017,-54.017) |
geographic |
Arctic Fairbanks Hicks Pacific Prince Creek |
geographic_facet |
Arctic Fairbanks Hicks Pacific Prince Creek |
genre |
Arctic Alaska |
genre_facet |
Arctic Alaska |
op_relation |
http://hdl.handle.net/11122/8942 Department of Geology and Geophysics |
_version_ |
1766346920639332352 |