Barendregt, Rene

Permanent URI for this collection

https://opus.uleth.ca/handle/10133/3554

Browse

Browsing Barendregt, Rene by Author "Duk-Rodkin, Alejandra"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Chronology and extent of late Cenozoic ice sheets in North America: a magnetostratigraphical assessment
    (Elsevier, 2011) Barendregt, René W.; Duk-Rodkin, Alejandra
    This paper summarises the advances which have been made in the magnetostratigraphic assessment of glacial and interglacial events of the past 3.0 million years, to facilitate the assignment of sediments to the Chrons and subchrons of the geomagnetic polarity timescale. In the absence of absolute dating tools, magnetostratigraphy affords a valuable means of assigning terrestrial ice age deposits to the geologic timescale, and most importantly, allows a correlation to be made with the more complete marine sedimentary record, where oxygen isotopic data also provide a robust paleotemperature record.
  • Thumbnail Image
    Item
    An extensive late Cenozoic terrestrial record of multiple glaciations preserved in the Tintina Trench of west-central Yukon: stratigraphy, paleomagnetism, palesols, and pollen
    (NRC Research Press, 2010) Duk-Rodkin, Alejandra; Barendregt, René W.; White, James M
    The Tintina Trench in west-central Yukon is a late Miocene graben formed along the antecedent early Tertiary Tintina fault. Since its formation the trench has served as a sediment trap for alluvial and glacial deposits. An extensive record of preglacial, glacial, and interglacial sediments spanning the late Pliocene to late Pleistocene has been preserved and is exposed today in modern landslide scars. This sedimentary record comprises multiple sequences of tills, outwash, mudflows, loess, and paleosols. The glacial sediments are the product of both local (montane) and regional (Cordilleran) ice advances that channeled into the trench, while loess and well-developed paleosols (brunisols and luvisols) reflect nonglacial and interglacial conditions, respectively. The Tintina Trench exposures provide the most complete record of glaciations for the region. Paleomagnetism, paleosols, and palynology provide age constraints for the geological events. A formal stratigraphic nomenclature is proposed for this region. The name West Tintina Trench Allogroup is assigned to the glacial–interglacial and nonglacial strata that occurs above a major regional Miocene–Pliocene unconformity. The allogroup spans the late Pliocene (3.6 Ma) to middle Pleistocene (0.126 Ma), based on magnetostratigraphy and pollen data. The sequence includes an alluvial deposit at the base, overlain by an extensive sequence of tills and outwash, and capped by loess. Paleosols and weathering horizons occur throughout the sequence. Tintina Trench; Beringia; glacial chronology; magnetostratigraphy; early and middle Pleistocene; Yukon paleoenvironments; Yukon paleosols; Yukon pollen; North American glaciations; West Tintina Trench Allogroup.
  • Thumbnail Image
    Item
    Stratigraphical record of glacials/interglacials in northwest Canada
    (Elsevier, 2011) Barendregt, René W.; Duk-Rodkin, Alejandra
    This chapter deals with stratigraphical correlations of glacial and interglacial deposits found in the northern Canadian Cordillera and in the northern Interior Plains of Canada. The sequences described here record multiple glacial events commencing at 2.7 Ma in the mountains and 1.6 Ma in the low latitude Arctic Islands. Extent and timing of these glaciations are based on magnetostratigraphy, tephrochronology, radiometric dating, paleosols and pollen.