Stratigraphy and Origin of the Paha Topography of Northwestern Illinois

Flemal, Ronald C.; Odom, Ira Edgar; Vail, Ronald G.

doi:10.1016/0033-5894(72)90041-5

Cited by 23 publications

(22 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, evidence from mid-continental dune fields and loess deposits (Flemal et al, 1972;Warren, 1976;Wells, 1983 and others) showed that winds south of the glacial limit were from the west and northwest during full glacial conditions, although model outputs indicated that anticyclonic (easterly) winds prevailed.…”

Section: Introductionmentioning

confidence: 98%

Relict Late Wisconsinan Dune Fields of the Northern Great Plains, Canada*

Wolfe

Huntley

Ollerhead

2006

gpq

View full text Add to dashboard Cite

Late Wisconsinan dune activity is investigated within the present-day boreal forest and parkland regions of the northern Great Plains, Canada, to extend the understanding of the spatial and temporal eolian record. Optical ages from stabilized sand dunes document the timing of past activity. Eolian activity ranges from about 16 ka in west-central Alberta to 9 ka in northwestern Saskatchewan. Between about 16 and 13 ka, dune activity in central Alberta occurred in an ice-proximal tundra setting along the margins of the Laurentide and Cordilleran ice sheets. Predominant dune-forming winds were from the west and northwest. Dune activity continued in this area between about 13 and 11 ka within parkland and grassland settings as the Laurentide Ice Sheet retreated to the northeast. Winds continued to blow from the west and northwest, and the climate was likely influenced by an increasingly dominant Pacific air mass. Also beginning at about 13 ka, dune-forming winds along the margins of the retreating Laurentide Ice Sheet were influenced by anticyclonic winds from the southeast that were maintained until about 9 ka. As the Laurentide Ice Sheet retreated, these southeasterly anticyclonic winds were successively replaced by winds from the northwest associated with the Pacific air mass. Dune activity across the region terminated in a time-transgressive manner from the southwest, at about 11 ka, to the northeast, at about 9 ka, with the establishment of boreal forest vegetation and reduced wind strength.Les auteurs étudient l’activité dunaire au Wisconsinien tardif dans la forêt boréale et la prairie-parc actuelles des Grandes Plaines septentrionales du Canada, afin d’approfondir les connaissances sur l’évolution spatiotemporelle de l’activité éolienne. Les âges optiques mesurés sur des dunes de sable stabilisées permettent de reconstituer la chronologie de l’activité passée. Les âges de l’activité éolienne s’échelonnent entre 16 ka dans le centre-ouest de l’Alberta et 9 ka dans le nord-ouest de la Saskatchewan. Entre 16 et 13 ka, l’activité dunaire dans le centre de l’Alberta a eu lieu dans un environnement de toundra juxtaglaciaire le long des marges des inlandsis laurentidien et cordillérien. Les vents efficaces prédominants soufflaient de l’ouest et du nord-ouest. L’activité dunaire s’est poursuivie dans cette région entre 13 et 11 ka dans des environnements de prairie-parc et de prairie herbageuse, avec le recul de l’Inlandsis laurentidien vers le nord-est. Les vents ont continué de souffler de l’ouest et du nord-ouest, et le climat a probablement été influencé par une masse d’air du Pacifique de plus en plus dominante. Également au début de 13 ka, les vents efficaces le long des marges de l’Inlandsis laurentidien en recul ont été influencées par des vents anticycloniques du sud-ouest, qui ont duré jusqu’à 9 ka. Avec le retrait de l’Inlandsis laurentidien, ces vents ont été successivement remplacés par des vents du nord-ouest associés à la masse d’air du Pacifique. L’activité dunaire dans la région s’est terminée de faç...

show abstract

Section: Introductionmentioning

confidence: 98%

Relict Late Wisconsinan Dune Fields of the Northern Great Plains, Canada*

Wolfe

Huntley

Ollerhead

2006

gpq

View full text Add to dashboard Cite

show abstract

“…The loess reaches a thickness of 12.4 m at the section described by Ruhe and Olsen (1978:11 -18). This particular feature has more a exaggerated streamlined appearance similar to the "whaleback" outlines described for Paha (parabolic loess dunes) of northwestern Illinois (Flemal et al, 1972;Rhue, 1969). Other braid cores in the Wabash Valley exhibit similar features.…”

Section: Eolian Processes and Peoria Loess Conesmentioning

confidence: 84%

The geomorphology of Sugar Loaf Mound: Prehistoric cemeteries and the formation of loess cones in the lower Wabash Valley

Stafford

1998

Geoarchaeology

View full text Add to dashboard Cite

“…Both the western side of Whiteside County and northern side of Rock Island County encompass the Illinois-type paha (versus Iowa-type paha) region (Flemal et al, 1972) (Fig. 1A).…”

Section: Illinoismentioning

confidence: 99%

“…The Illinois-type paha are parallel to subparallel ridges oriented NW-SE (Fig. The landforms are contiguous over a very large area (Flemal et al, 1972). The landforms are contiguous over a very large area (Flemal et al, 1972).…”

Section: Illinoismentioning

confidence: 99%

“…The regional Illinois-type paha topography consists of oriented, contiguous, elliptical, and elongated ridges of either unconsolidated sediment or bedrock capped by loess, lying adjacent to valleys with the same orientation (Flemal et al, 1972). The regional Illinois-type paha topography consists of oriented, contiguous, elliptical, and elongated ridges of either unconsolidated sediment or bedrock capped by loess, lying adjacent to valleys with the same orientation (Flemal et al, 1972).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Devon Island's Oriented Landforms as an Analog to Illinois-Type Paha

Iannicelli¹

2003

Polar Geography

View full text Add to dashboard Cite

Illinois-type paha are unusual regional landforms located in northwestern Illinois, USA, consisting of inactive, oriented, oblong ridges composed of either loess or bedrock capped by loess. A recent study reidentified the paha of Illinois as relict oriented, snowmelt interfluves, formed by erosion from snowdrifts or snow dunes occupying oriented valleys alternating with inter-valley ridges during the cold phase(s) of the Pleistocene Epoch. Devon Island, located in the high Arctic, exhibits similar regional, oriented inter-valley ridges and adjacent oriented valleys with the added feature of overlying, oriented snowbanks or snow dunes. The similarities between both regional landforms include morphology, dimensions, parallelism, orientation to the (paleo)wind; and the fact that the oriented dissection was formed irrespective of the steepest direction of the general slope. Oriented nival landforms with the same peculiar characteristics also exist on Resolute, Cornwallis Island, adjacent to Devon Island. Nivation compounded by indirect influence of the wind is proposed as the causal agent for all of the previously mentioned landforms.

show abstract

Stratigraphy and Origin of the Paha Topography of Northwestern Illinois

Cited by 23 publications

References 2 publications

Relict Late Wisconsinan Dune Fields of the Northern Great Plains, Canada*

Relict Late Wisconsinan Dune Fields of the Northern Great Plains, Canada*

The geomorphology of Sugar Loaf Mound: Prehistoric cemeteries and the formation of loess cones in the lower Wabash Valley

Devon Island's Oriented Landforms as an Analog to Illinois-Type Paha

Contact Info

Product

Resources

About