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Full-Text Articles in Paleontology
Scanning Electron Microscopic Study Of Quartz Sand Surface Features, Ash Hollow Formation, Ogallala Group, Western Nebraska, Patricia E. Helland, Robert F. Diffendal Jr.
Scanning Electron Microscopic Study Of Quartz Sand Surface Features, Ash Hollow Formation, Ogallala Group, Western Nebraska, Patricia E. Helland, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
In field studies of the late Tertiary Ash Hollow Formation of the Ogallala Group in western Nebraska the alluvial deposits are composed of large volumes of sand and gravel up to large cobbles. Because the current understanding of the climate of the region at the time of deposition does not provide for a source for deposits of this character, a scanning electron microscopic study of the surface features on the quartz sand grains from these sediments was undertaken. Nine samples, collected from locations in Banner, Morrill and Keith Counties, were examined to see if they had one or more of …
Late Paleozoic Cyclic Sedimentation In Southeastern Nebraska: A Field Guide, Roger K. Pabian, Robert F. Diffendal Jr.
Late Paleozoic Cyclic Sedimentation In Southeastern Nebraska: A Field Guide, Roger K. Pabian, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
People studying and collecting sedimentary rocks, minerals, and fossils in eastern Nebraska often find that locating rock exposures can be difficult. Most of the rolling hills in the eastern sixth of the state are underlain by thick, interlayered, glacial deposits, loess (windblown silt), and alluvium (stream-deposited sediments) of very young geologic age. These sediments cover the bedrock in most of that area. Natural exposures and human excavations of bedrock are mostly confined to the sides and floors of stream valleys. However, in the southeasternmost counties of the state, the younger sediment cover is commonly thin or absent. Pawnee and Richardson …
The Succession Of Late Cenozoic Volcanic Ashes In The Great Plains: A Progress Report, John Boellstorff
The Succession Of Late Cenozoic Volcanic Ashes In The Great Plains: A Progress Report, John Boellstorff
School of Natural Resources: Faculty Publications
No abstract provided.
Microfossils From The Big Springs Limestone (Pennsylvanian) In Nebraska, Robert F. Diffendal Jr.
Microfossils From The Big Springs Limestone (Pennsylvanian) In Nebraska, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
Sand-sized residues from partial acetic acid digestion of three samples of the Big Springs Limestone Member of the Lecompton Limestone (Pennsylvanian) from two localities in Cass County, Nebraska, have yielded sixteen genera of microfossils from five major groups of organisms and numerous other whole and partial fossils from seven other groups not identified to the genus level. These fossils include: Protozoa (fusulinids*); Porifera (one spicule type); Bryozoa (two undetermined genera); Brachiopoda (fragments); Gastropoda (two undetermined forms); Ostracoda (Bairdia*, Hollinella*, Moorites*, and one undetermined genus); Crinoidea (whole and partial ossicles*); Echinoidea (whole and partial spines and spine bases*); Holothuroidea (Achistrum …
Microfossils From The Upper Severy Shale (Pennsylvanian) Near Dubois, Nebraska, Robert F. Diffendal Jr.
Microfossils From The Upper Severy Shale (Pennsylvanian) Near Dubois, Nebraska, Robert F. Diffendal Jr.
School of Natural Resources: Faculty Publications
Organic rich limestone nodules within the Severy Shale Formation collected directly above the Nodaway Coal Member near DuBois, Nebraska, have yielded a rich microflora and microfauna. The microflora includes Triletes megaspores, seeds, cuticle, and pieces of wood with well preserved structures. The microfaunal skeletal material is either partially or completely replaced by pyrite, marcasite, or, in rare cases, by sphalerite. The following major invertebrate groups and genera within these groups have been identified to date: Bryozoa (one undetermined genus); Brachiopoda (Juresania) ; Gastropoda (four undetermined genera); Ammonoidea (one undetermined genus); Ostracoda (Amphissites, Coryellites, Hollinella, Macrocypris); Echinoidea (five spine types); and …