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Morrison, R. B.

Publications and source records attributed to Morrison, R. B..

27 records · Page 2

Assessment of flood damage in Arizona by means of ERTS-1 imagery

ERTS-1 MSS images clearly show two important effects of a large flood in southeastern Arizona - the extent of inundation and the areas affected by servere sediment deposition and erosion - although the images were made a week and a half after the flood. On October 20 and 21, 1972, the upper Gila River had its third-largest flood on record. Peak flows attained about 42,000 and 82,000 cubic feet a second at Duncan and Safford, Arizona, respectively. The first ERTS-1 images after the flood were made on November 1 and 2. The inundated area is best displayed on the infrared bands, particularly on band 7, where it appears as a belt along the river that is distinctly darker than adjoining parts of the flood plain. This dark belt does not appear on ERTS images that predate the flood. Presumably the low infrared reflectance of this belt is caused by still-moist soil and by flood-stressed vegetation. Inundation limits mapped from ERTS imagery agree well with those obtained by aerial photography during the flood and by ground surveys.

Morrison, R. B.↗

A study of Quaternary landforms and materials in the Midwest and Great Plains

The author has identified the following significant results. Measurements made from prints of ERTS-1, MSS 5 images, show practical limits of detectability for this imagery in the Midwest. The smallest high contrast object detectable has an approximate measured diameter of 150 feet. The smallest clearly identifiable cultural feature is roughly 300 feet for high contrast, and 400 to 500 feet for low contrast objects. Rural roadways, with an average width of 75 feet, are clearly defined due to high reflectivity, linearity, and the instantaneous field of view of the scanner. On the infrared a farm pond slightly greater than one acre is detectable. Crop and natural foliage cover in the Midwest during summar months obscures geologic and soils information and hinders detailed mapping. In the western Great Plains large-scale mapping of this kind may be possible, even at this time of year. In southwestern Iowa, topographic and drainage system anomalies, revealed by the imagery, are related to the slope of and depth to the buried bedrock surface. In eastern Iowa land use classification can be done from ERTS-1 imagery.

Morrison, R. B.↗

Geologic terrain mapping from earth-satellite and ultra-high aerial photographs

A proposal is made for mapping from aerial photographs from the EROS program. Three kinds of maps (geomorphic or landform, soil, and surficial deposit) are being prepared at 1:250,000 scale for an 8000-square-mile area between Tucson and Ajo, Arizona. Nine cameras used on NASA mission 101 provided color, color infrared, and multispectral air photos from about 60,000 feet above the terrain and with photo scales ranging from 1:60,000 to 1:240,000. This area was selected because it provides a good sample of desert terrain and is suited for improving and testing the photointerpretive techniques for mapping geologic terrain features with small-scale photos.

Morrison, R. B.↗