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On the basis of work by several authors (Maurin and Lathram, 1977),
(Fischer and Lathram, 1973) plans are now being made (Gryc, written
communication, 1977) to drill a Lands at-detected apparent geologic
structure in northern Alaska to a depth of approximately 19,775 feet this
The results, if favorable, will help establish Landsat as an
important exploration tool.
Over 600 representatives from a number of petroleum and petroleum
exploration companies attended the most recent William T. Pecora Symposium
in Sioux Falls, s. D., in October of 1977. Both in presented papers and
in private discussions, it became apparent that the petroleum industry 18
not only the largest single customer of data from Landsat, but that they
are now using the data routinely to improve their total exploration
and planning programs.
Many companies have established their own
computerized data listings, and several are routinely using computer
analysis methods in addition to conventional interpretation procedures.
One company representative stated that the characteristics of
broad overview and low sun angle perspective provided by Landsat images
have enabled his company to select targets for detailed geological and
geophysical exploration. Another representative stated that Landsat
Images of the United States are being used extensively and are providing
new structural information that will extend known oil fields in the
Miller (1977) demonstrated how Landsat data have assisted in
exploration in Kenya.
He states that "ERTS (Landsat) studies have the
advantage of very quick Interpretation over new areas and regions.
work saves time and money and gives a substantial basis for new ideas."
In 1977 he reported the discovery of a large and thick sequence of
sedimentary rocks in southern Sudan that provide a new target for oil
exploration, which is now underway (Miller and Vandenakker, 1977).
Mosaics of the conterminous United States compiled by the Soil
Conservation Service for NASA have been analyzed by U.S. Geological Survey
geologists interested in linear features that may be of tectonic
Mosaics at scales of 1:5,000,000 and 1:1,000,000 were used
to identify and evaluate new features and to re-evaluate previously
known geologic features.
Field work in northern Sonora, Mexico, has
confirmed early interpretations by Salas (1977) that the occurrence of
major mineral deposits are closely related to the intersection of linear
features that are major fracture systems.
This confirmation is
supported by geochemical and geophysical evidence (Raines, 1977, and
Kleinkopf and others, 1977).
Rowan and others (1974) demonstrated that the combination of digital
computer processing of band ratios and color compositing of Landsat
Multispectral Scanner (MSS) images could be used to detect and map areas
of hydrothermally altered rocks associated with ore deposits and to
discriminate most major rock types in south-central Nevada.
Schmidt (1976) used computer enhanced Landsat imagery to examine the
characteristics of known copper deposits in Pakistan.
He then examined
the imagery to find areas that have similar spectral and textural
He found 19 areas that he considered to be potential
sites for the presence of mineralized rock and was able to confirm
surface mineralization by field inspection at seven of these.
similar methods, Dykstra and Bimic (1977) have extended the geologic
Information of the area to the east and confirmed many of the early
Use of Landsat to observe water-quality conditions
Landsat data have been successfully used in water-quality and environmental applications. The Program of the International Hydrological
Decade (IHD) had as a major objective the monitoring of water-quality
conditions in the Great Lakes.
As an adjunct exercise to the IHD,
EROS Program collaborated with the National Oceanic and Atmospheric
Administration (NOAA), NASA, the Canada Centre for Inland Waters, and
Guelph and McMaster Universities in studying the applicability of
Falconer and others (1975) used photo-optical techniques
to enhance water features recorded in the data and clearly showed turbidity
plumes from the Welland Canal and Niagara River. They also showed
turbidity pattems interrupted by offshore bars, and steel mill and
municipal effluents in Hamilton Harbour.
Tonal differences extending into
the lake from the Humber River at Toronto were clearly depicted as well as
additional unidentified effluent discharges.
The study demonstrated
the capability of Landsat to detect sources and movement of natural
pollutants and municipal and industrial wastes into major water bodies. Linear features, presumably Internal waves, which are indicative of
lake dynamics, were also depicted on the enhanced imagery.
of floating or near-surface biotic materials were detected, illustrating
the suitability of the data for certain types of ecological analyses.
Allan Strong of NOAA, in cooperation with the EROS Program, prepared
& water-quality classification of eastern Lake Ontario using digital
analysis techniques and color codings to distinguish carbonate precipitates, chlorophylls, algae, and floating oil slicks.