Publications

A field study was conducted in four differentially irrigated plots of alfalfa (Medicago sativa L.) planted in Shiprock sandy loam (coarseloamy, mixed, mesic Typic Haplargid) to assess spectral reflectance for estimating the crop coefficient (Kc), defined here as the ratio of actual to potential evapotranspiration (ET). A bidirectional reflectance factor was measured using a three-channel...

This paper documents the procedures, results, and final products of a digital analysis of Landsat data used to produce a vegetation and landcover map of the Blackfoot River watershed in southeastern Idaho. Resource classes were identified at two levels of detail: generalized Level I classes (for example, forest land and wetland) and detailed Levels II and III classes (for example...

The purpose of this report is to summarize the progress in use of digital image analysis techniques in developing a conceptual model for assessing porphyry copper mineral potential. The study area consists of approximately the southern one-half of the 1? by 3? Nabesna quadrangle in east-central Alaska. The digital geologic data base consists of data compiled under the Alaskan Mineral...

Edge enhancement is a technique that can be considered, to a first order, a correction for the modulation transfer function of an imaging system. Digital imaging systems sample a continuous function at discrete intervals so that high-frequency information cannot be recorded at the same precision as lower frequency data. Because of this, fine detail or edge information in digital images...

The gold, diamond and manganese deposits of Ghana have attracted commercial interest, but appropriate geophysical data to delineate the tectonic setting of these and other deposits have been lacking until recently. Recent gravity surveys, however, now cover about 75% of the country. When used in a synthesis of the sometimes contradictory existing theories about the geology and...

Lineament analysis of a Landsat Imagery mosaic (scale 1:1,000,000) of northeast Sugdan indicate significant curvilinear as well as rectilinear fracture patterns of possible Precambrian age. Rectilinear features trend dominantly in N-S (± 10°), NNW and ENE, and less commonly in NW and EW directions. The Precambrian fractures closely match, and have possibly accommodated the Tertiary...

No abstract available.

Landsat digital data were used to evaluate lesser prairie chicken (Tympanuchus pallidicinctus) habitats in western Oklahoma. Data for 7 (4,144 ha) study areas, 4 in shinnery oak (Quercus havardii), and 3 in sand sagebrush (Artemisia filifolia) rangeland, were analyzed using the Interactive Digital Image Manipulation System at the EROS Center. In shinnery oak rangeland, density of...

As part of a cooperative project between the U.S. Geological Survey and the Bureau of Land Management, changes in albedo (percentage of light reflected from the ground) were calculated and mapped from Landsat images for an area in northwestern Arizona for three periods: August 26, 1977, to September 3, 1979; September 3, 1979, to August 28, 1980; and August 26, 1977, to August 28, 1980...

Four dates of Heat Capacity Mapping Mission (HCMM) data were analyzed to evaluate the utility of HCMM thermal data for evaluating depth to shallow groundwater. During the summer, shallow water tables can create lower soil temperatures throughout the diurnal temperature cycle. Because of large spatial and temporal ground cover variations, HCMM daytime radiometric temperatures alone did...

No abstract available.

In 1959, Sigurdur Thorarinsson published his first complete classification of the 13 principal types of basaltic volcanoes of Iceland (Figure 1). In 1968, Thorarinsson published a modification of his earlier classification scheme. Both landform classifications were based on the relationship of the type of eruptive products (lava, lava and tephra, or tephra), number of eruptions (one or...