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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Analysis of thematic mapper simulator data acquired during winter season over Pearl River, Mississippi, test site

Digital processed aircraft-acquired thematic mapping simulator (TMS) data collected during the winter season over a forested site in southern Mississippi are presented to investigate the utility of TMS data for use in forest inventories and monitoring. Analyses indicated that TMS data are capable of delineating the mixed forest land cover type to an accuracy of 92.5 % correct. The accuracies associated with river bottom forest and pine forest were 95.5 and 91.5 % correct. The accuracies associated with river bottom forest and pine forest were 95.5 and 91.5 % correct, respectively. The figures reflect the performance for products produced using the best subset of channels for each forest cover type. It was found that the choice of channels (subsets) has a significant effect on the accuracy of classification produced, and that the same channels are not the most desirable for all three forest types studied. Both supervised and unsupervised spectral signature development techniques are evaluated; the unsupervised methods proved unacceptable for the three forest types considered.

Anderson, J. E.↗
NASA NTRS1982

The Snake River Plain, Idaho - Representative of a new category of volcanism

Studies of the volcanic geology of the Snake River Plain, Idaho, and comparison with other basaltic regions suggest a new category of volcanic activity, termed basaltic plains volcanism. Typified by the Snake River Plain, this style of volcanism is intermediate between basaltic flood (or plateau) eruptions and Hawaiian volcanism. Characteristics that are common to both Hawaiian and plains volcanism are: multiple lava flow units which erupt primarily from point sources, formation of low shields, and frequent emplacement through lava tubes or channels. Characteristics that are common to both flood basalts and plains volcanism are: high volume flows, vents aligned along rift zones, and planar surfaces. The recognition of plains volcanism in other areas provides a means to interpret the style of eruption and volcanic history.

Greeley, R.↗
NASA NTRS1981

Application of remote sensing to land and water resource planning: The Pocomoke River Basin, Maryland

Because of the size of the Pocomoke River Basin, the inaccessibility of certain areas, and study time constraints, several remote sensing techniques were used to collect base information on the river corridor, (a 23.2 km channel) and on a 1.2 km wooded floodplain. This information provided an adequate understanding of the environment and its resources, thus enabling effective management options to be designed. The remote sensing techniques used for assessment included manual analysis of high altitude color-infrared photography, computer-assisted analysis of LANDSAT-2 imagery, and the application of airborne oceanographic Lidar for topographic mapping. Results show that each techniques was valuable in providing the needed base data necessary for resource planning.

Wildesen, S. E.↗
NASA NTRS1984

Experiments examining the shapes of isolated bars in comparison with those occurring in braided rivers

Sand bars and islands within braided rivers have characteristic rhomboid or diamond shapes, often becoming very complex in form as the density of islands increases. Similar forms are observed in the martian outflow channels where the islands occur in groups. This contrasts with the more isolated martian islands which have airfoil shapes, as do isolated streamlined islands in rivers and in the Channeled Scabland. These observations indicate that the bar and island forms are controlled by the density of the islands, with increasing island interaction and flow modification as the density increases. As a continuation of previous flume experiments on the shapes of isolated islands, a new series of experiments investigate the modifications produced by a progressive increase in island density, finally leading to a true braided system.

Komar, P. D.↗
NASA NTRS1983

Integration of Landsat data into the Saginaw River Basin geographic information system

One of the objectives of the Saginaw River Basin study is related to the development of a computer model to predict flood damages. The computer model is to be operational in June 1985. In order to achieve this objective, the input of land-use data into a data base consisting of 198,000 grid cells will be required. A planning technique using Spatial Analysis Methodology (SAM) was developed by the Corps of Engineers Hydrologic Engineering Center (HEC) to systematically handle these data. The HEC-SAM system uses the spatially oriented map data in a series of data management and analysis software programs for input to the Corps hydrologic and environmental models. Attention is given to data base development, Landsat digital data, the placement of the Landsat data into the grid cell data base, and the development of the land cover classification. The Landsat-2 MSS scene covering 85 percent of the Saginaw River Basin was geometrically corrected to a UTM coordinate system.

Mckim, H. L.↗
NASA NTRS1985

Paleogene Vertebrate Paleontology, Geology and Remote Sensing in the Wind River Basin

Biostratigraphic and lithostratigraphic studies were used to correlate different events in the geologic evolution of the northeastern part of the Wind River Basin and have suggested several conclusions. Laterally equivalent exposures of the Lysite member from Cedar Ridge to Bridger Creek show a gradation in lithology from interbedded boulder conglomerates and sandstones to interbedded lenticular sandstones and mudstones to interbedded carbonaceous shales, coals and tabular sandstones. This gradation suggests a shift from alluvial fan to braided stream to paludal or lacustrine sedimentary environments during the late early Eocene. The Lysite and Lost Cabin members of the Wind River Formation are in fault contact in the Bridger Creek area and may intertongue to the east along Cedar Ridge. Ways in which remote sensing could be used in these studies are discussed.

Stucky, R. K.↗
NASA NTRS1985

Peat landforms along the Albany River, northern Ontario. An ecological study of peat landforms in Canada and Alaska

During the summer of 1985 a field investigation was started in the Hudson Bay lowland region of northern Ontario, which represents the largest expanse of peatland in North America and is an important sink in the global carbon cycle. A key area in the lowlands is situated along the Albany River near the confluence of the Chepay River. Here the striking vegetation-landforms are transitional between those found on the bed of Glacial Lake Agassiz in northern Minnesota and southern Manitoba and the more northern peatlands in the Hudson Bay lowland region. In peatland studies elsewhere the landform patterns have been used not only to classify different peatland types but also as an indicator of potential developmetnal trends. The study area is generally defined by that covered by the TM scene E-40062-15532 taken on Sept. 16, 1982. The purpose of the field work is to acquire sufficent information to interpret the TM imagery and test various hypotheses on peatland development on the gasis of the pattern transitions.

Glaser, P. H.↗
NASA NTRS1986

Development of Archean crust in the Wind River Mountains, Wyoming

The Wind River Mountains are a NW-SE trending range composed almost entirely of high-grade Archean gneiss and granites which were thrust to the west over Phanerozoic sediments during the Laramide orogeny. Late Archean granites make up over 50% of the exposed crust and dominates the southern half of the range, while older orthogneisses and magnatites form most of the northen half of the range. Locally these gneisses contain enclaves of supracrustal rocks, which appear to be the oldest preserved rocks in the range. Detailed work in the Medina Mountain area of the central Wind River Mountains and reconnaissance work throughout much of the northern part of the range has allowed definition of the sequence of events which marked crustal development in this area. The sequence of events are described.

Frost, C. D.↗
NASA NTRS1985

Ohio River main stem study - The role of geographic information systems and remote sensing in flood damage assessments

The Pittsburgh District, Corps of Engineers, has conducted feasibility analyses of various procedures for performing flood damage assessments along the main stem of the Ohio River. Procedures using traditional, although highly automated, techniques and those based on geographic information systems have been evaluated at a test site, the City of New Martinsville, Wetzel County, WV. The flood damage assessments of the test site developed from an automated, conventional structure-by-structure appraisal served as the ground truth data set. A geographic information system was developed for the test site which includes data on hydraulic reach, ground and reference flood elevations, and land use/cover. Damage assessments were made using land use mapping developed from an exhaustive field inspection of each tax parcel. This ground truth condition was considered to provide the best comparison of flood damages to the conventional approach. Also, four land use/cover data sets were developed from Thematic Mapper Simulator (TMS) and Landsat-4 Thematic Mapper (TM) data. One of these was also used to develop a damage assessment of the test site. This paper presents the comparative absolute and relative accuracies of land use/cover mapping and flood damage assessments, and the recommended role of geographic information systems aided by remote sensing for conducting flood damage assessments and updates along the main stem of the Ohio River.

Edwardo, H. A.↗
NASA NTRS1986

The Red River Valley archeological project

The Red River Valley Archeology Project is a long-term effort involving numerous individuals and institutions engaged in archeological investigations in the Texas and Oklahoma portions of the Red River Valley. To date the focus of the project was on site location. The project acquired both Thermal Infrared Multispectral Scanner (TIMS), TMS, and color infrared photographs over a significant portion of the project area in an effort to define signatures for archeological sites and to assist in the detailed geomorphological mapping of the flood plain. Preliminary analysis of acquired data indicates that both the TIMS and TMS can make a substantial contribution to landform definition, the identification of cultural resources, and to the clarification of site-landform correlations in this riverine environment.

Bennett, Jack↗
NASA NTRS1987

Influence of the Yukon River on the Bering Sea

The distribution of near-surface, turbid water, discharged by the Yukon River, was studied based on analysis of satellite imagery. The interannual analyses indicates that the net flow of near-surface, turbid water is northward of the delta across the entrance to Norton Sound. Only turbid water to the east enters Norton Sound and consists of 25% of the total area. Approximately 10% of the water circulates into the sound along the southern coast and is lost to view in the vicinity of Unalakleet. Suspended sediments transported by this southern circulation are primarily deposited along the southern coast. Three distinct zones within the turbid water were identified based on relative brightness levels. These zones appear to be primarily related to differences in suspended-sediment concentrations and position of the sediments in the water column. The extent of turbid water varies seasonally. It is most extensive June through October even though discharge of the Yukon River decreases substantially after July.

Dean, K.↗
NASA NTRS1988

Nd and Sr isotope systematics of river water suspended material - Implications for crustal evolution

Sm-Nd and Rb-Sr isotopic data on suspended material from rivers draining a variety of rock types and ages are presented. The bulk load of rivers and their source rocks are compared in terms of their isotopic characteristics and model ages. The Nd and Sr isotope systematics of the upper crust exposed to weathering are obtained along with the Nd model age distribution of the North American continental surface. The average Sm-Nd and Rb-Sr isotopic parameters for the upper continental crust today are refined.

Goldstein, Steven J.↗
NASA NTRS1988

Buoyant surface jet analysis of the Yukon River

Thermal infrared satellite imagery of the discharge from the Yukon River obtained on July 5, 1985 was compared with hydraulic theory for the dilution of buoyant surface jets. In a crossflow, the theory predicts that the plume will follow an x exp 1/3 trajectory where x is distance alongshore, and that the plume temperature will decay according to x exp - 1/6 due to mixing with the receiving water. Measurements of the Yukon River discharge indicate very good agreement with the predicted trajectory, and less, but acceptable, agreement with the predicted dilution. Large scale thermal fronts are also observable in the thermal imagery; the fronts may be associated with excursions of the plume due to tidal currents.

Gosink, J. P.↗
NASA NTRS1989

The plume of the Yukon River in relation to the oceanography of the Bering Sea

The ecosystem of the northern Bering-Sea shelf was studied using data from the NOAA Very High Resolution Radiometer and AVHRR and the Landsat MSS and Thematic Mapper (TM) in conjunction with shipboard measurements. Emphasis was placed on the influence of the Yukon River on this inner shelf environment and on the evaluation of the utility of the new Landsat TM data for oceanography. It was found that the patterns of water mass distribution obtained from satellite images agreed reasonably well with the areal patterns of temperature, salinity, and phytoplankton distributions. The AVHRR, MSS, and TM data show that the Yukon-River discharge is warmer and more turbid than the surrounding coastal water that originates to the south; thus, the Yukon water contributes to the higher temperatures and lower transmissivity of the coastal water. The high resolution of the TM thermal IR band made it possible to observe complex patterns and structures in the surface water that could not be resolved on previous data sets.

Dean, Kenneson G.↗
NASA NTRS1990

Revision of the Wind River faunas, early Eocene of central Wyoming. X - Bunophorus (Mammalia, Artiodactyla)

Research on the holotypes and large collections of the species of Wasatchia and Bunophorus is reviewed. It is concluded that Bunophorus is a senior synonym of Wasatchia and includes six valid species, namely, B. etsagicus, B. grangeri, B. pattersoni, B. macropternus, B. sinclairi, and B. robustus. B. sinclairi includes two penecontemporaneous geographic variants: B.s. sinclairi from the Wind River, Piceance and Green River basins, and B.s. robinsoni, n. ssp., from the Huerfano Basin.

Stucky, Richard K.↗
NASA NTRS1991

The application of geologic remote sensing to vertebrate biostratigraphy - General results from the Wind River Basin, Wyoming

Since 1986, remote sensing images derived from satellite and aircraft-borne sensor data have been used to study the stratigraphy and sedimentology of the vertebrate-bearing Wind River and Wagon Bed formations in the Wind River Basin (Wyoming). Landsat 5 TM and aircraft Thermal Infrared Multispectral Scanner data were combined with conventional geologic analyses. The remote sensing data have contributed significantly to: (1) geologic mapping at the formation, member, and bed levels; (2) stratigraphic correlation; (3) reconstruction of ancient depositional environments; and (4) identification of structural complexity. This information is critical to vertebrate paleontology in providing the stratigraphic, sedimentologic, and structural framework required for evolutionary and paleoecologic studies. Of primary importance is the ability to map at minimal cost the geology of large areas (20,000 sq km or greater) at a high level of precision. Remote sensing data can be especially useful in geologically and paleontologically unexplored or poorly understood regions.

Stucky, Richard K.↗
NASA NTRS2000

Multispectral In-situ Measurements of Organic Matter and Chlorophyll Fluorescence in Seawater: Documenting the Intrusion of the Mississippi River Plume in the West Florida Shelf

We performed multispectral in-situ fluorescence measurement of colored dissolved organic matter and chlorophyll in surface water of the West Florida Shelf using West Labs Spectral absorption and Fluorescence Instrument (SAFIre). Continuous measurements underway allowed us to simultaneously map the dispersion of riverine organic material and chlorophyll on the shelf. By using two fluorescence emission ratios we were able to differentiate between riverine and marine CDOM. Our data also showed unusually high concentrations of CDOM offshore. These were attributed to an intrusion of the Mississippi River Plume. We performed limited comparisons between in-situ chlorophyll concentrations measured with SAFIre and chlorophyll values obtained from SeaWiFS satellite data using OC4 and MODIS algorithm. Our results show that, although both algorithms overestimated chlorophyll, MODIS performed better than OC4, particularly in areas with high CDOM concentrations. Analysis of the relationship between chlorophyll and CDOM concentrations within the study area showed regional variability causes by differences in river source.

DelCastillo, Carlos E.↗
NASA NTRS2002

Mapping CDOM Concentration in Waters Influenced by the Mississippi River Plume

Colored dissolved organic matter (CDOM) is often an important component of the organic carbon pool in river-dominated coastal margins. CDOM directly influences remote sensing applications through its strong absorption in the UV and blue regions of the spectrum. This effect can complicate the use of chlorophyll a retrieval algorithms and phytoplankton production models that are based on remotely sensed ocean color. As freshwater input is the principle source of CDOM in coastal margins, CDOM distribution can often be described by conservative mixing with open ocean waters and may serve as an optical tracer of riverine water. Hence, there is considerable interest in the ability to accurately measure and map CDOM concentrations as well as understand the processes that govern the optical properties and distribution of CDOM in coastal environments. We are examining CDOM dynamics in the waters influenced by the Mississippi River plume. Our program incorporates discrete samples, flow-through measurements, and remote sensing. CDOM absorption spectra of discrete samples are measured at sea using a portable, multiple pathlength waveguide system. A SAFire multi-spectral fluorescence meter provides spectral characterization of CDOM (fluorescence and absorption) using a ship flow-through system for continuous surface mapping. In situ reflectance spectra are obtained by a hand held spectroradiometer. Remotely sensed images are obtained from the SeaWiFS and CRIS (Coastal Research Imaging Spectrometer) instruments. We describe here the instruments used, sampling protocols employed, and the relationships derived between in situ measurements and remotely sensed data for this optically complex environment.

Miller, Richard L.↗