A Note on the Most Recent Ichthyosaur Known: an Isolated Coracoid from the Upper Campanian of Saskatchewan (Reptilia, Ichthyosauria)

1973 ◽  
Vol 10 (8) ◽  
pp. 1346-1349
Author(s):  
C. McGowan

The geologically youngest ichthyosaur specimen is described: an isolated, partial coracoid from the Bearpaw Formation of the South Saskatchewan river valley (Upper Campanian) near Stewart Valley, Saskatchewan. The final extinction of the Ichthyosauria is briefly discussed, and the possibility that it may not have been brought about by competition from the mosasaurs is examined.

1970 ◽  
Vol 7 (6) ◽  
pp. 1579-1583 ◽  
Author(s):  
Peter P. David

The first known Mazama ash occurrence in Saskatchewan was discovered in eolian sediments at the top of the bluffs on the South Saskatchewan River valley 20 miles (~32 km) west of Leader, Saskatchewan. The chemical composition and the refractive index of the volcanic glass serve for the definite identification of the Mazama ash. The ash layer is a useful horizon marker in the eolian sediments, for it represents a time-break at 6 600 years ago. It is suggested that eolian deposits in similar sedimentary environments be examined for other occurrences of the Mazama ash.


Author(s):  
David A. Lindsey ◽  
William H. Langer ◽  
Linda Scott Cummings ◽  
John F. Shary ◽  
Joseph E. Taggart ◽  
...  

2001 ◽  
Vol 38 (11) ◽  
pp. 1601-1613 ◽  
Author(s):  
E A Christiansen ◽  
E Karl Sauer

The Saskatoon Low is a collapse structure that formed as a result of dissolution of salt from the Middle Devonian Prairie Evaporite Formation. In this study, the collapse has affected the Upper Cretaceous Lea Park, Judith River, and Bearpaw formations of the Montana Group; the Early and Middle Pleistocene Mennon, Dundurn, and Warman formations of the Sutherland Group; and the Late Pleistocene Floral, Battleford, and Haultain formations of the Saskatoon Group. Locally, the collapse is about 180 m, which is about equal to the thickness of the salt. The first phase of collapse took place after deposition of the Ardkenneth Member of the Bearpaw Formation and before glaciation or during a pre-Illinoian glaciation. The second phase of collapse occurred during the Battleford glaciation (Late Wisconsinan). Prior to deposition of the Battleford Formation, the Saskatoon Low was glacially eroded, removing the Sutherland Group and the Floral Formation. After the glacial erosion, up to 110 m of soft till of the Battleford Formation and up to 77 m of deltaic sand, silt, and clay of the Haultain Formation were deposited in the Saskatoon Low. Lastly, the South Saskatchewan River eroded up to about 40 m into the deltaic sediment and tills before up to about 15 m of Pike Lake Formation was deposited. The Haultain and Pike Lake formations are new stratigraphic units.


1965 ◽  
Vol 5 (40) ◽  
pp. 385-397 ◽  
Author(s):  
Daniel B. Krinsley

Abstract A morainal sequence in south-west Yukon Territory, Canada, records at least four major, successively less extensive glaciations from ice fields in the St. Elias Mountains south of the glaciated area. The Nisling Moraine flanks the Klondike Plateau in a belt t km. wide to an altitude of 1,040 m., 12 km. north-east of Snag. The northernmost lobe of this moraine terminates at the junction of the Donjek and White Rivers, 120 km, from the nearest source of ice, Klutlan Glacier. 11 km. north-east of Snag, the prominent front of the Donjek Moraine lies 180 m. below the front of the Nisling Moraine. The northernmost lobe of the Donjek Moraine terminates 106 km. north of Klutlan Glacier and occupies the lower courses of canyons cut into the Nisling Moraine. The front of the Snag Moraine crosses the White River valley 210 m. below the front of the Donjek Moraine and 96 km. north of Klutlan Glacier. The Tchawsahmon Moraine, 38 km. north-west of Klutlan Glacier. consists of a series of concentric ridges, the oldest of which impounded Tchawsahmon Lake. Provisional correlations suggest that the Nisling Moraine is pre-Illinoian; the Donjek, Illinoian; the Snag, pre-classical Wisconsin; and the Tchawsahmon, classical Wisconsin.


1965 ◽  
Vol 5 (40) ◽  
pp. 385-397 ◽  
Author(s):  
Daniel B. Krinsley

AbstractA morainal sequence in south-west Yukon Territory, Canada, records at least four major, successively less extensive glaciations from ice fields in the St. Elias Mountains south of the glaciated area.The Nisling Moraine flanks the Klondike Plateau in a belt t km. wide to an altitude of 1,040 m., 12 km. north-east of Snag. The northernmost lobe of this moraine terminates at the junction of the Donjek and White Rivers, 120 km, from the nearest source of ice, Klutlan Glacier. 11 km. north-east of Snag, the prominent front of the Donjek Moraine lies 180 m. below the front of the Nisling Moraine. The northernmost lobe of the Donjek Moraine terminates 106 km. north of Klutlan Glacier and occupies the lower courses of canyons cut into the Nisling Moraine. The front of the Snag Moraine crosses the White River valley 210 m. below the front of the Donjek Moraine and 96 km. north of Klutlan Glacier. The Tchawsahmon Moraine, 38 km. north-west of Klutlan Glacier. consists of a series of concentric ridges, the oldest of which impounded Tchawsahmon Lake.Provisional correlations suggest that the Nisling Moraine is pre-Illinoian; the Donjek, Illinoian; the Snag, pre-classical Wisconsin; and the Tchawsahmon, classical Wisconsin.


Sign in / Sign up

Export Citation Format

Share Document