Multispectral Scanner Data Research Articles

Use of Landsat multispectral scanner data for detection and reconnaissance mapping of iron oxide staining in mineral exploration, central East Greenland

Test area; color anomalous hydrothermal alteration associated with stockwork molybdenum mineralization. Tertiary Malmbjerg molybdenum occurrence. Interactive digital image processing system combined with computerized color plots. Special ratio and factor analysis techniques. The best results with ratio techniques are obtained when band 4/band 5 is displayed as cyan (red), band 5/band 7 as magenta (green), and band 6/band 7 as yellow (blue). A characteristic pink to orange color corresponds to areas of limonitic rocks. Using factor analysis, color composites displaying F2 as magenta (green), F3 as cyan (red), and F4 as yellow (blue) with a visually determined color stretch discriminates very effectively with yellow-orange to red-orange colors representing limonitic rocks. More than 50 significant rust zones located. Ratio and factor analysis techniques were applied to reconnaissance mapping of Precambrian metamorphic and Devonian volcanic terrains covering more than 30,000 km 2 of ice-free area in a province of 500 km long by 300 km wide, resulting in the localization of 38 major (surface area > 0.5 km 2 ) rust zones in Precambrian metamorphic terrain.--Modified journal abstract.

Relationships between the type of residential area and the aspects of surface temperature and solar reflectance (based on digital image analysis using airborne multispectral scanner data)

Relationships between the type of residential area and the aspects of surface temperature and solar reflectance (based on digital image analysis using airborne multispectral scanner data)

Characteristic Variations in Spectral Reflectance of Selected Eroded Alfisols

AbstractSoil cores taken at incremental depths from a Typic Hapludalf were examined to investigate the relationships among the chemical, physical, and spectral reflectance properties which occur as the proportion of various horizons change in the soil samples. Results of these studies were compared to soil samples taken from selected Typic Hapludalfs in Indiana which represented various degrees of natural erosion. Two important properties affecting the spectral reflectance of these soils were the organic matter and iron oxide contents. High organic matter contents tend to cause the reflectance to be low and give a concave character to the spectral response in the 0.5‐ to 0.8‐µm region. High iron oxide content along with the reduction in organic matter tends to cause an increase in the overall spectral response; however, the presence of iron oxides causes a leveling off of the spectral response in the 0.8‐ to 1.1‐µm region. Intermediate contents of organic matter and iron oxide affect the spectral response relative to their proportions within the soil sample. These distinctive reflectance characteristics can be related to the severity of erosion. Comparison of laboratory data to simulated Landsat data suggests that satellite multispectral scanner data can be useful in detecting eroded soils. Separability of erosion classes for the Alfisols studied was best determined by observing the slope of the simulated Landsat plots between 0.75 and 0.95 µm, bands 3 and 4. As the severity of erosion increases, the slope of the plot decreases in this region.

Directional reflectance properties determined by analysis of airborne multispectral scanner data and atmospheric correction

Directional reflectance properties of natural surfaces are very important in the interpretation of remotely sensed data. The analysis of multispectral scanner data shows a distinct dependence on scan angle, wavelength (0.4–1.1 μm), and classes (e.g., bare soil, vegetation). This relationship can be described by polynomials determined by regression methods. Atmospheric effects are computed with a simple model by parametrization of the multiple scattered skylight. The model permits a quick and sufficient estimation of the airlight, depending on the data collection conditions. Comparisons of the scanner data with the corresponding model yield the following results: The differences between airborne and ground measurements are due to atmospheric effects. The directional variation in brightness is mainly caused by the object itself with the exception of short wavelengths and/or a very low albedo. The hue shift of vegetation is essentially produced by the object and modified by the atmosphere. Taking into account the directional reflectance properties in a direction-dependent classification procedure results in an improvement of up to 20% in comparison with algorithms used so far. Quantitative relationships between ground measurements and radiation measurements by airborne sensors including atmospheric effects can be determined with the proposed methods.

Nontidal wetland mapping in South Carolina using airborne multispectral scanner data

High resolution multispectral scanner (MSS) imagery of Savannah River nontidal wetlands were analyzed to identify 1) useful spectral bands for discriminating among National Wetland Inventory classes, 2) where the classes cluster in n-dimensional feature space, and 3) what wetland classification accuracies can be expected. Spectral measurements in the green (0.55–0.60 μm), red (0.65–0.70 μm), and near-infrared wavelengths (0.70–0.79 μm and 0.92–1.10 μm) provided the most useful information. Emergent marsh (both persistent and nonpersistent), scrub-shrub, mixed deciduous swamp forest, and mixed deciduous upland forest were found to cluster in somewhat predictable regions of 2- and 3-dimensional feature space. The overall classification accuracy of the Steel Creek delta study area was 83% and was assessed by comparing the remote sensing derived thematic map with 1325 linear meters of transects sampled in situ. These results suggest that high resolution aircraft MSS data can provide detailed vegetation type information for mapping both thermally affected and rejuvenating nontidal wetland in the South Carolina Savannah River Swamp System.

A CLASS DEFINITION OF LAND-COVER BY USE OF MSS DATA

A class definition method has been developed for extracting the land-cover information from multispectral scanner (MSS) data. The method is based on the statistical verification tested by F-values and t-values, which are estimated by multiple regression analysis in a stepwise manner. It has been applied to Landsat and aircraft MSS data. Based on the statistical verification, the original land-cover classes which are interpreted manually with color aerial photographs, have been consolidated in sequence. Consequently, thirteen classes for the Landsat MSS data and eleven classes for the aircraft MSS data are defined.

The estimation of green-leaf-area index from remotely sensed airborne multispectral scanner data

Abstract Airborne multispectral scanning system (MSS) data from the Natural Environment Research Council's MSS-82 project were used to estimate the green-leaf-area index (GLAI) of an area of semi-natural and agricultural limestone grassland. This research is the pilot study of a five phase investigation which will ultimately test the feasibility of using airborne and spaceborne MSS data to estimate GLAI over large areas. The pilot study was designed around four stages: (i) derivation of the relationship between multispectral reflectance and vegetation amount using ground radiometric data collected in the field, (ii) production of a perpendicular-vegetation index (PVI) image, (iii) production of a GLAI image using the relationship between PVI and GLAI and (iv) accuracy assessment of the resultant GLAI image. Due to a number of project- and environment-specific problems the proposed methodology was modified and GLAI was predicted to an accuracy of 50-86 per cent at the 95 per cent confidence level. For the ...

A Statistical Evaluation of the Advantages of LANDSAT Thematic Mapper Data in Comparison to Multispectral Scanner Data

A study designed on the basis of a fixed-effects, three factor, two-level analysis or variance (ANOVA) was conducted to quantify the effect of Thematic Mapper (TM) sensor improvements on classification accuracy using TM data acquired over the Washinton, DC, area on November 2, 1982. The TM data were systematically degraded spatially, spectrally, and radiometrically to simulate the effect of changing each individual sensor parameter separately, and in conjunction with other sensor characteristics, to ultimately simulate Multispectral Scanner (MSS) data characteristics. The greatest level of variance was accounted for by the spectral waveband variable, providing an average increase in classification accuracy of 5.85 percent. This increase constituted a 21-percent relative improvement from TM data with respect to Landsat MSS data [i. e., percent relative improvement = (high accuracy value-low accuracy value)/low accuracy value X 100]. The second greatest amount of variance was accounted for by the ?radiometric? variable (i. e., bit quantization level). This provided a 5.25-percent increase in percent correctly classified pixels, which constitutes a 19-percent relative improvement of TM over MSS data due to quantization level. Spatial resolution accounted for the lowest source of variability in the observed classification accuracies, with an overall average decrease of 0.7 percent. This constituted a 2-percent relative degradation from TM data with respect to MSS data. Only the differences found for the spectral waveband combinations and the quantization level were statistically significant at ? levels of 0.01 to 0.001.

LANDSAT-4 MSS And Thematic Mapper Data Quality And Information Content Analysis

Landsat-4 Thematic Mapper and Multispectral Scanner data were analyzed to obtain information on data quality and information content. Geometric evaluations were performed to test band-to-band registration accuracy. Thematic Mapper overall system resolution was evaluated using scene objects which demonstrated sharp high contrast edge responses. Radiometric evaluation included detector relative calibration, effects of resampling, and coherent noise effects. Information content evaluation was carried out using clustering, principal components, transformed divergence separability measure, and numerous supervised classifiers on data from Iowa and Illinois. A detailed spectral class analysis (multispectral classification) was carried out on data from the Des Moines, Iowa area to compare the information content of the MSS and TM for a large number of scene classes.

Characterization of LANDSAT-4 MSS And TM Digital Image Data

Engineering analyses conducted to assess image data quality are described and results are presented for the Landsat-4 Multispectral Scanner (MSS) and Thematic Mapper (TM). Also, coincident data from the two sensors are compared. Macroscopic studies addressed trends and characteristics of full frames of data, while "microscopic" studies assessed differences between individual detector responses. Raw data, radiometrically corrected data, and fully corrected data were analyzed, as well as special calibration data. The Landsat-4 MSS was found to produce data of high quality, comparable to previous Landsats, except for a low-level coherent noise effect which is unique to the current sensor. Radiometric relationships between Landsat-2 and -3 MSS's and the Landsat-4 MSS were established through empirical analysis of simultaneously acquired data. The TM was found to produce image data of very good spatial resolution and overall good radiometric data quality, showing improvements over MSS. Radiometric equalization of detector responses was found to be close to the theoretical limit of quantization error, except for two relatively low-amplitude artifacts. One is a difference in response that depends on the direction of mirror scan. This produces scan-angle effects superimposed on scene-related effects. The second is a tendency for level shifts to occur between mirror scans at random times but with correlations between detector responses. Two forms or patterns of level shift were identified, corresponding to four system noise states. Preliminary correction models and/or procedures have been developed and recommended for further evaluation.

Spectral Variability of LANDSAT-4 Thematic Mapper And Multispectral Scanner Data for Selected Crop And Forest Cover Types

The performance of both the Landsat-4 TM and MSS sensors is evaluated through the analysis of image and digital data simultaneously acquired over agricultural and forestry study sites in California. Spectral statistics extracted for selected cover types include band means, variances, coefficients of variation, range values, skewness, kurtosis, and covariance and correlation matrices. Spectral characteristics are evaluated through analysis of these statistics and interpretation of image products. Image products are used to visually represent significant spectral variations between the TM bands. Significant results include: 1) the overall spectral, spatial, and radiometric quality of the TM data are excellent; 2) discrimination of crop types on single-date image data is significantly improved by the addition of the first short-wave infrared band (TM5); 3) the thermal infrared data (TM6) allows the discrimination of agricultural and forestry cover types based on differences in their radiant temperature responses; and 4) the higher TM spatial resolution (28.5 m versus 57 m) provides the ability to discriminate small agricultural fields and boundaries, forest stand boundary conditions, road and stream networks in rough terrain, and small clearings resulting from various forest management practices.

Objective assessment of Advanced Very High Resolution Radiometer data for land cover mapping

The validity of using data from the Advanced Very High Resolution Radiometer (AVHRR) of the satellites NOAA-6 and NOAA-7 for land cover mapping is assessed by making comparisons with much higher resolution LANDSAT multi-spectral scanner (MSS) data. Near synchronous data for both systems are analysed for test sites in the Imperial Valley, California, the Nile Delta, and southern Italy. The results strongly indicate that despite the very coarse resolution of the AVHRR data compared with conventional MSS data they are sufficiently strongly correlated to suggest that the former have significant potential for land cover mapping, especially at small scales and for large areas. Hence the outstanding benefits of AVHRR data, namely their high temporal frequency, relative cheapness and low data volumes for image processing, may readily be taken advantage of for such tasks.

Locating shoreline changes in the Porttipahta (Finland) water reservoir by using multitemporal landsat data

Both scientific and technical investigations and the planning of water reservoir areas for different purposes all require accurate base information on water areas in the form of preliminary orientation maps. These are in principle most easily obtained by using the Landsat multispectral scanner (MSS) data in CCT form. Computer-aided analysis such data allows us to survey and interpret the water reservoir environment both in time and in space on a scale which is very laborious through in-situ mapping. Repetitive coverages of Landsat MSS digital imagery data over the Porttipahta water reservoir in northern Finland have been processed by using a computer for enhancement of changing shoreline features. Temporal variations in the water reservoir area have been mapped to accentuate the Landsat CCT data-processing method for volumetric estimation of stored water, for preparing topographic shoreline maps of different water levels, and for shore environment change analysis. The multi-year analysis of digital Landsat data gives important information about environmental changes within the water reservoir area in a relatively short processing period. In the case of reservoirs in flat or mosaic-topography areas the mixed pixels may lead to some difficulties.

The application of multispectral scanner data to coastal monitoring

The application of multispectral scanner data to coastal monitoring

Surface albedo and the Sahel drought

The persistence of the Sahel drought, which reached a peak in 1973, appears to be typical for such dry episodes over past decades and centuries1–3. Such strong persistence can be understood if a strong positive feedback mechanism is operating, partly driven by changes in surface properties4,5. The key factors in the mechanisms thus far studied are the surface albedo and the soil moisture, both of which affect the radiation balance at the surface, the first directly, the second indirectly through its influence on the latent heat flux. We have now studied the evolution of the albedo of this region since 1972. We find that dry season albedo in the Sahel (notably Ferlo and Gondo regions, see Fig. 1b) declined from a maximum close to 0.30 in 1973 to values close to 0.20 in 1979. This decline is consistent with changes in plant cover determined by analysis of spectral changes in the Landsat multispectral scanner (MSS) data and field studies6,7.

The skylab lunar multispectral scanner data

Skylab S-192 multispectral scanner data, in 12 bands covering wavelengths from 0.41 to 2.3 μm, have been investigated to identify and classify geologic units of the lunar surface. Seventeen spectral cluster classes have been identified, seven in the highlands, seven in the maria, and three of which occur in both or in border regions. This finding may be roughly indicative of the relative heterogeneity of these regions. It implies that there is as much heterogeneity in the highlands as in the maria. This work extends the spectral and aerial coverage of similar studies of the lunar surface and provides useful data for comparison for most of the lunar near side.

Comparison of Landsat Multispectral Scanner and Thematic Mapper Data from Wind River Basin, Wyoming: ABSTRACT

Landsat Multispectral Scanner (MSS) data are limited by MSS spatial resolution (80 m or 262 ft) and bandwidth selection. Landsat 4 Thematic Mapper (TM) data have greatly enhanced spatial resolution (30 m or 98 ft) and TM operates in spectral bands suited to geologic interpretation. To compare the two systems, three images centered over the Wind River basin of Wyoming were obtained. Two were TM images--a false color composite (FCC) and a natural color composite (NCC)--and the third was an MSS image. A systematic analysis of drainage, landforms, geologic structure, gross lithologic characteristics, lineaments, and curvilinears was performed on the three images. Drainage density and landform distinction were greatly enhanced on the TM images. Geologic features such as faults, strike and dip, folds, and lithologic characteristics are often difficult to distinguish on the MSS image but are readily apparent on the TM images. The lineament-curvilinear analysis of the MSS image showed longer but less distinct linear features. In comparison, the TM images allowed interpretation of shorter but more distinct linear elements, providing a more accurate delineation of the actual dimensions of the geologic features which these lineaments are thought to represent. An analysis of the oil product on present in the study area showed 75% of the surface productive structures were delineated on the TM images, whereas only the most obvious structures were visible on the MSS image. End_of_Article - Last_Page 937------------

Comparison of simulated thematic mapper data and multispectral scanner data

Single date and multidate Landsat MSS and Thematic Mapper (TM) data were simulated utilizing helicopter spectrometer data from 5 years of commercial field data and actual field boundaries and land use from a 5 × 6- nautical mile sample segment in Kingsbury County, South Dakota. Single-date simulations for MSS and TM clusters showed a decrease in mixed pixels on the borders of fields with TM, but an increase in the number of TM clusters for cover types which have significant within-field variability.

Functional equivalence of spectral vegetation indices

Numerous formulae, vegetation indices, have been developed to reduce multispectral scanner (MSS) data to a single number for assessing vegetation characteristics such as species, leaf area, stress, and biomass. Part I of this report gives the history and formulae of some four dozen vegetation indices. Studies investigating the empirical relationships among vegetation indices are summarized. Part II of this report develops the idea of two vegetation indices being functionally equivalent: Two vegetation indices are taken to be equivalent for making a set of decisions, if the decisions made on the basis of one index could have been equally well made on the basis of the other index. The utility of these ideas is explored in the context of alarm models and graphical displays. Several widely used indices are shown to be equivalent.

Landsat and Field Studies Link Structural Lineaments and Mineralization in St. Francois Mountains, Missouri: ABSTRACT

Late-stage Precambrian granites in the St. Francois Mountains are among the most uraniferous in North America. The St. Francois province has potential for uranium mineralization of economic importance, especially in the later differentiates. Structural lineaments and circular features displayed on images produced by electronic data processing of Landsat multispectral scanner data may be related to late-stage intrusives with uranium potential. Strong north-south lineaments and associated circular and arcuate features may correspond to major weaknesses in the earth's crust along which fracturing, faulting, and volcanism have occurred. The strike of the lineaments transects the older dominant northwest-southeast and northeast-southwest structural grain of the region. This, and the remarkable preservation of Precambrian structures of volcanic origin, indicate that the lineaments may be related to late-stage, uranium- and thorium-rich intrusives. The Ironton lineament, a major north-south lineament, is closely related spatiall to Precambrian iron and manganese deposits. Field work along the Ironton lineament suggests that it is related to a late period of Precambrian volcanism and that structural deformation along the lineament continued into early Paleozoic time. Areas of faulting, shearing, and hydrothermal alteration affecting both Precambrian and Paleozoic rocks have been located. A circular feature along the lineament has been found to be centered by a manganese deposit of possible hydrothermal origin. End_of_Article - Last_Page 947------------