888 research outputs found
Glacial drift in the Driftless Area of Northeast Iowa
https://ir.uiowa.edu/igs_ri/1001/thumbnail.jp
The Cenozoic History of the Upper Mississippi River
Changes in the course of the Mississippi River caused by successive glacial invasions are described. Recently discovered evidence is presented bearing on the establishment of the general course of the River between Iowa and Wisconsin and Iowa and Illinois in Nebraskan time. There are also some rock terraces believed to indicate the approximate depth to which the valley had been cut by Kansan time. The Illinoian history of the river and of Lake Calvin are reviewed. The details of the present course of the river involve the definition and partial subsequent removal of Wisconsin glacio-fluvial material
New Exposures of Upland Nebraskan Drift in Northeastern Iowa
Remnants of Nebraskan drift, as recently exposed capping a high Mississippi River bluff in the city of Dubuque and occupying caverns and sinks in the Mississippi River bluff near Guttenberg, are described and interpreted
Current Early Paleozoic Classification in Iowa
Presentation and discussion of a classification of Cambrian, Ordovician, and Silurian strata recently adopted by the Iowa Geological Survey for use in this state
Pleistocene Histroy of Mississippi River (Abstract)
From its earliest known record immediately prior to the advance of the Nebraskan glacier to the present time the course of Mississippi River was affected by each advancing ice sheet in turn. The Nebraskan glacier displaced it to the east, the Kansan glacier shoved it farther east, the Illinoian glacier pushed it back west, with the retreat of the Illinoian ice it took an easterly course again, the Iowan or earliest Wisconsin glacier diverted it from one minor channel to another, the Green River lobe of the Tazewell Wisconsin ice sheet forced it back into a western course and started the Rock Island rapids, and the latest Wisconsin or Mankato invasion resulted in a great fill and the details of the course as it now is
The Status of Sedimentation in Iowa
Iowa need not be ashamed of the part her geologists have played, either in the past history of sedimentation, or in the recently renewed American activity on this important, but too long neglected subject. There being no igneous rocks in situ within the state and practically no exposures of metamorphic rocks, all the work which has been done on the geology of the state during the years is more or less closely related with sedimentation. The more recent investigations of breccias by Professor W. H. Norton, of gumbotils by Dr. George F. Kay, of Pennsylvanian stratigraphy and structure by Dr. John L. Tilton, and of clays by Dr. Sidney L. Galpin, constitute important contributions to knowledge of sedimentary rocks and the conditions under which they are formed. At the State University there is a research course in sedimentation and a sedimentation laboratory is in process of establishment
Schedules for the Field Descriptions of Sedimentary Rocks
An explanation of the schedules recently reported by a subcommittee of the committee on sedimentation of the National Research Council, and presentation to each of those present of mimeographed copies of the introduction to these schedules, and of printed copies of the schedules themselves. These materials were furnished the writer by Dr. M. I. Goldman, Chairman of the committee
Photometric analysis of a space shuttle water venting
Presented here is a preliminary interpretation of a recent experiment conducted on Space Shuttle Discovery (Mission STS 29) in which a stream of liquid supply water was vented into space at twilight. The data consist of video images of the sunlight-scattering water/ice particle cloud that formed, taken by visible light-sensitive intensified cameras both onboard the spacecraft and at the AMOS ground station near the trajectory's nadir. This experiment was undertaken to study the phenomenology of water columns injected into the low-Earth orbital environment, and to provide information about the lifetime of ice particles that may recontact Space Shuttle orbits later. The findings about the composition of the cloud have relevance to ionospheric plasma depletion experiments and to the dynamics of the interaction of orbiting spacecraft with the environment
Wheat as a cattle feed
Cover title.Includes bibliographical references
Yearling heifers and steers for beef production
Cover title.Includes bibliographical references
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