Helicosporous fungi and Early Eocene pollen, Eureka Sound Group, Axel Heiberg Island, Northwest Territories

1991 ◽  
Vol 28 (3) ◽  
pp. 364-371 ◽  
Author(s):  
R. M. Kalgutkar ◽  
D. J. McIntyre
Keyword(s):  
Northwest Territories ◽  
Fungal Spores ◽  
Forest Vegetation ◽  
Temperate Climate ◽  
Early Eocene ◽  
Swamp Forest ◽  
Pollen And Spores ◽  
Axel Heiberg Island

Two types of helicosporous fungal spores were recovered from a sample from the Iceberg Bay Formation, Eureka Sound Group, at Strand Fiord, Axel Heiberg Island. These spores appear to be identical to those produced by the Recent genera Helicoön, Helicodendron, and Helicosporium. The associated pollen flora indicates an Early Eocene age for the sample and interval from which it was collected. The pollen and spores suggest that swamp forest vegetation, dominated by trees of Taxodiaceae–Cupressaceae and growing in a temperate climate, was present at or close to the site of deposition.

Early Tertiary thermotectonic history of the northern Yukon and adjacent Northwest Territories, Arctic Canada

1997 ◽  
Vol 34 (10) ◽  
pp. 1366-1378 ◽  
Author(s):  
Paul B. O'Sullivan ◽  
Larry S. Lane
Keyword(s):  
Northwest Territories ◽  
Fission Track ◽  
Middle Eocene ◽  
Geothermal Gradient ◽  
Crystalline Rock ◽  
Early Eocene ◽  
Channel Formation ◽  
Rapid Cooling ◽  
Early Tertiary ◽  
History Of

Apatite fission-track data from 16 sedimentary and crystalline rock samples indicate rapid regional Early Eocene denudation within the onshore Beaufort–Mackenzie region of northwestern Canada. Rocks exposed in the area of the Big Fish River, Northwest Territories, cooled rapidly from paleotemperatures of >80–110 °C to <6 0°C at ca. 56 ± 2 Ma, probably in response to kilometre-scale denudation associated with regional structuring. The data suggest the region experienced a geothermal gradient of ~28 °C/km prior to rapid cooling, with ~2.7 km of section having been removed from the top of the exposed section in the Moose Channel Formation and ~3.8 km from the top of the exposed Cuesta Creek Member. Farther to the west, rocks exposed in the headwaters of the Blow River in the Barn Mountains, Yukon Territories, were exposed to paleotemperatures above 110 °C in the Late Paleocene prior to rapid cooling from these elevated paleotemperatures due to kilometre-scale denudation at ca. 56 ± 2 Ma. Exposure of these samples at the surface today requires that a minimum of ~3.8 km of denudation occurred since they began cooling below ~110 °C. The apatite analyses indicate that rocks exposed in the northern Yukon and Northwest Territories experienced rapid cooling during the Early Eocene in response to kilometre-scale denudation, associated with early Tertiary folding and thrusting in the northern Cordillera. Early Eocene cooling–uplift ages for onshore sections are slightly older than the Middle Eocene ages previously documented for the adjacent offshore foldbelt and suggest that the deformation progressed toward the foreland of the foldbelt through time.

scholarly journals Comparative palynology of Macrotermes sp. mounds and Vespula vulgaris nests on the University of Lagos campus, Akoka: preliminary study

2017 ◽  
Vol 57 (2) ◽  
pp. 397-406
Author(s):  
Michael Babatunde Adebayo ◽  
Peter Adegbenga Adeonipekun ◽  
Matthew Adesanya Adeleye ◽  
Kehinde Ajike Kemabonta
Keyword(s):  
Secondary Forest ◽  
Fungal Spores ◽  
Environmental Studies ◽  
Pollen Assemblage ◽  
Termite Mounds ◽  
Swamp Forest ◽  
Palynological Analysis ◽  
Vespula Vulgaris ◽  
Wasp Nests ◽  
The University

AbstractIn order to assess the environmental indicator potential of wasp nests and termite mounds, the palynomorph content of three randomly selectedMacrotermessp. mounds (termitaria) and twoVespula vulgarisnests collected on the University of Lagos campus were examined. Palynological analysis showed the presence of 298 well-preserved palynomorphs showing characteristic morphological features. The recovered palynomorphs included pollen, pteridophyte spores and fungal spores, along with insect parts (106), diatoms (7) and a protist (1). The pollen assemblage of termite mounds comprised 78 pollen and pteridophyte spores, with Poaceae and Arecaceae pollen as dominants. In the wasp nest the pollen assemblage comprised 28 pollen and spore taxa, with Poaceae and Arecaceae pollen also dominant. Both mounds and nests had, besides diatoms, six pollen and spore taxa: Poaceae, Amaranthaceae, Pteridophyte spores, Arecaceae,Raffiasp. andRhizophorasp. Vegetational grouping of the recovered pollen and spores indicated five phytoecological groups: secondary forest, mangrove swamp forest, freshwater, open vegetation and Poaceae. In statistical analyses, termite mounds had a higher species richness value (2.08 as compared to 1.99 from the wasp nests), while the wasp nests had a higher species diversity value (0.997 as compared to 0.845 from the termite mounds). Pollen analyses of the termite mounds and wasp nests suggest that both could be useful tools in environmental studies. This is the first attempt to evaluate the potential of termite mounds and wasps nest as natural pollen accumulators in Nigeria. The results suggest new possibilities for the use of the pollen records preserved in termite mounds and wasp nests for environmental studies.

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