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Computer enhancement, particularly contrast-stretching, reveals a previously unnoticed east-west structural zone across a Landsat image of the southern Brazilian Precambrian shield. In this zone occur the only known economic or near-economic deposits of gold, tin, and copper. Such deposits are typically localized by small east-west structural elements. Non-economic copper occurrences...

Mineralogical differences between altered rocks and most unaltered rocks in south-central Nevada cause visible and near-infrared (0.45 to 2.4 mu m) spectral-reflectance differences which can be used to discriminate these broad categories of rocks in multispectral images. The most important mineralogical differences are the increased abundance of goethite, hematite, and...

Color composites of Landsat Multispectral Scanner ratio images that display variations in the intensity of ferric-iron absorption bands are highly effective for mapping limonitic altered rocks but are ineffective for mapping nonlimonitic altered rocks. Analysis of 0.45- to 2.5-µm field and laboratory spectra shows that iron-deficient opalized rocks in the...

No abstract available....

This bibliography contains citations of selected publications and technical reports dealing with the application of Landsat digital data analysis techniques to agriculture, forestry, and range management problems. All of the citations were published between 1973 and 1977. The citations reference publications and reports which discuss specific analysis techniques and specific...

Rock-type classification by digital-computer processing of Landsat-1 (formerly ERTS-1) multispectral scanner data has been used to select 23 prospecting targets in the Chagai District, Pakistan, 5 of which have proved to be large areas of hydrothermally altered porphyry containing pyrite. The known porphyry copper deposit at Saindak was used as...

Five Data Collection Platforms (DCP) were integrated electronically with thermall sensing systems, emplaced and operated in an analog mode at selected thermally significant volcanic and geothermal sites. The DCP's transmitted 3260 messages comprising 26,080 ambient, surface, and near-surface temperature records at an accuracy of ±1.15 °C for 1121 instrument days...

Examination of images from Nimbus, NOAA and Landsat satellites has revealed a series of lineaments in the earth's surface in Alaska 1000 km or more in length (fig. 1). These lineaments occur as alinements of surface geologic structures, linear valleys or ridges, and linear changes in tonal contrast marking differences...

No abstract available....

A demonstration of the utility of Landsat imagery for quickly and cheaply estimating irrigated land area was conducted in the Klamath River basin of Oregon. Landsat color composite images, at 1:250,000 scale and acquired on two dates during the 1975 growing season, were interpreted. Irrigated lands were delineated manually, and...

To date, relatively few studies have dealt with crop-soil interactions as they affect the appearance of agricultural areas on Landsat imagery, and hence crop and soil classification or the analysis of agricultural land use.The Image 100, a computer-based data analysis system which allows an interpreter to interact directly and rapidly with Landsat computer...

No abstract available....

The Tanacross quadrangle, consisting of 17,400 km 2 (6,700 mi 2) in east-central Alaska, was investigated by an interdisciplinary research team for the purpose of assessing the mineral resource potential of the quadrangle. This report provides the background information for a folio of maps on the geology, geophysics, reconnaissance geochemistry,...

Land-cover information is needed to select subbasins within the New River basin, Tennessee, for the study of hydrologic processes and also is needed to transfer study results to other sites affected by coal mining. It was believed that data recorded by the first Earth Resources Technology Satellite (Landsat-1) could be...

In this study of Landsat imagery for the Tanacross quadrangle, Alaska, two fundamentally different types of images were used: (1) a black and white, single band, Landsat mosaic of Alaska, constructed with images that are not computer-enhanced; and (2) various types of computer-enhanced Landsat images....

Recent work in the Nabesna and McCarthy quadrangles, Alaska, indicates that computer-enhanced LANDSAT imagery shows many of the known mineral deposits and can help in the prediction of potential mineral occurrences. False color, "simulated natural color" and color ratio techniques, were used successfully in conjunction with a black and white,...

Lineaments were detected on SKYLAB photographs by stereo viewing , projection viewing, and composite viewing. Large well yields of 25 gal/min or more can be obtained in the study area by locating future wells on SKYLAB lineaments rather than on lineaments detected on either high-altitude aerial photographs, LANDSAT images, or...