Abstract Detail



Paleobotany

Zaborac-Reed, Stephanie [1], Ickert-Bond, Steffi [2], Friend, Steve [3], Pigg, Kathleen [4].

Filling in the Gaps: Evaluating a Miocene Flora Near Anchor Point, Kenai Lowland, Alaska.

In 2016, local fossil enthusiast Steve Friend contacted the University of Alaska Museum of the North about a large slab of rock containing bird trackways. This ultimately ignited interest in a newly recognized leaf compression site at the Anchor Point State Recreation Area, Kenai Peninsula, south central Alaska. This site is now being studied systematically in order to contribute to our understanding of the paleontological history of the Kenai Lowlands. This flora is assigned to the Beluga Formation, of presumed mid-late Miocene age, based on previous surveys of the area. Three mid-Miocene to Mio-Pliocene floristic stages from the Kenai Lowlands - the Seldovian, Homerian and Clamgulchian - are known from studies by Wolfe and Tanai (1980), Wolfe et al. (1966), and Reinink-Smith et al. (2017). These studies have documented climatic and floristic transitions during the Miocene and Pliocene. Two of these floristic stages are associated with the Beluga Formation (the Homerian and the Clamgulchian). In this preliminary study, we have identified the following megafossil taxa: Equisetum rhizomes; taxodiaceous foliage as well as pollen cones and seed cones, including those of Metasequoia; leaves of Betula and Alnus; Alnus pistillate infructescences; possible juglandaceous pollen catkins; leaves potentially assignable to Ilex, Quercus and Ribes; and a fruit resembling Trochodendron. Wood, charcoal fragments and possibly leaf cuticles are also present in the matrix, and will be prepared for microscopy. The matrix will also be processed for palynomorph study. Some taxa typical for Miocene sites in western North America, including these Kenai Lowland floras, have been found at Anchor Point (Betula, Alnus, Metasequoia, and Quercus). Of particular interest is the identification of Trochodendron. Extinct genera related to Trochodendron are known from several Miocene sites in the Pacific Northwest, Japan and Kamchatka. The genus is Asian in distribution today, as is Metasequoia (Manchester et al. 2021). The presence of possible juglandaceous pollen catkins and Trochodendron at Anchor Point suggests that the Anchor Point flora may represent an intermediate floral composition in comparison to the previously described floras of the Kenai Lowlands.


1 - University of Alaska Fairbanks, P.O. Box 757500, Fairbanks, AK, 99775, USA
2 - University Of Alaska Fairbanks, Herbarium (ALA) And Dept. Of Biology And Wildlife, University Of Alaska Fairbanks, 1962 Yukon Dr., Fairbanks, AK, 99775, United States
3 - PO Box 1455, Anchor Point, 99556, USA
4 - Arizona State University, SCHOOL OF LIFE SCIENCES FACULTY & ADMIN, Box 874501, Tempe, AZ, 85287, United States

Keywords:
Miocene
paleobotany
Beluga Formation
Kenai Lowlands
Anchor Point.

Presentation Type: Oral Paper
Number: PB1007
Abstract ID:616
Candidate for Awards:Isabel Cookson Award,Maynard F. Moseley Award


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