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Full-Text Articles in Geology
Megaclasts In Alluvial Fills From The Ogallala Group (Miocene), Banner, Kimball, And Morrill Counties, Nebraska, Robert F. Diffendal Jr.
Megaclasts In Alluvial Fills From The Ogallala Group (Miocene), Banner, Kimball, And Morrill Counties, Nebraska, Robert F. Diffendal Jr.
Robert F. Diffendal, Jr., Publications
Locally derived blocks and boulders (megaclasts) occur in conglomerate and in sand and gravel fills of channels in the Ogallala Group (Miocene) at localities in Banner, Kimball, and Morrill counties in western Nebraska. Some of the megaclasts are up to one or more orders of magnitude larger than the largest distantly derived grains in the sediments surrounding them. A number of these megaclasts probably moved downslope by mass wasting from outcrop sites on paleovalley sides and were later transported by running water. Other blocks and boulders were eroded by streams from bedrock along channel sides and then were transported by …
An Irvingtonian Fauna From The Oldest Quaternary Alluvium In Eastern Pumpkin Creek Valley, Morrill And Banner Counties, Nebraska, R. George Corner, Robert F. Diffendal Jr.
An Irvingtonian Fauna From The Oldest Quaternary Alluvium In Eastern Pumpkin Creek Valley, Morrill And Banner Counties, Nebraska, R. George Corner, Robert F. Diffendal Jr.
Robert F. Diffendal, Jr., Publications
Vertebrate fossils of Mammuthus meridionalis (Nesti) and Equus sp. cf. E. scotti Gidley occur at two sites in the capping alluvium of the highest strath terrace along the south side of Pumpkin Creek Valley, Nebraska. The presence of these two species supports the conclusion that the age of the capping sediments is probably early Irvingtonian (early Pleistocene).
Asymmetrical Distribution Of Quaternary Alluvial Fills, Pumpkin Creek Drainage Basin, Western Nebraska, Robert F. Diffendal Jr., R. George Corner
Asymmetrical Distribution Of Quaternary Alluvial Fills, Pumpkin Creek Drainage Basin, Western Nebraska, Robert F. Diffendal Jr., R. George Corner
Robert F. Diffendal, Jr., Publications
A remnant alluvial fill of early Pleistocene age exposed in Pumpkin Creek Valley, Banner and Morrill counties, Nebraska, has yielded fossils of Mammuthus meridionalis (Nesti) and Equus sp. cf. E. scotti Gidley. Younger fill remnants of trunk and tributary streams allow a refinement of earlier views on the development of the Pumpkin Creek drainage basin during the Quaternary Period. Ancestral Pumpkin Creek both shifted to the north and entrenched its valley several times during the Quaternary Period leaving alluvial fills at three levels or more south of the present creek. Piracy of the headwaters of ancestral Pumpkin Creek took …