Paleomagnetic evidence for the rotation of Alaska
Paleomagnetic evidence for rotation of Alaska relative to North America
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Paleomagnetic evidence for rotation of Alaska relative to North America
Communications satellite for Alaska and Mountain States TV defined using computerized synthesis program
Seismic refraction profiles of ash flow in Valley of Ten Thousand Smokes, Alaska, obtaining P wave velocities
Infrared and color photography for water inlet survey in Alaska
Auroral conjugacy observations over Alaska and south of New Zealand, noting correlation with geomagnetic field lines
Vegetative and geologic mapping of Western Seward Peninsula, Alaska, based on ERTS-1 imagery
Impact of ERTS-1 images on surveys of forest insect infestations in Cook Inlet Basin, Alaska
ERTS-1 imagery of geological structures and lineaments in Alaska
Regional tectonics in Alaska based on ERTS-1 imagery
ERTS-1 imagery of coastal currents and sediment transport in Cook Inlet, Alaska
Coastal sediment distribution in Cook Inlet, Alaska
The author has identified the following significant results. The Yukon-Tanana uplands north and east of Fairbanks appear, on ERTS-1 imagery, to be composed of a number of large-scale (approximately 100 kilometers square) crustal blocks. The boundaries of these blocks appear to be defined by a number of northeast-striking lineaments which form the major river valleys of the area. Principal among these are the valleys of the Salcha River, the Cehan River, and the Chatanika River. These lineaments are all seismically active, and are thus presumed to be faults. This parallel set of lineaments appears to be intersected at various angles by a secondary set of faults trending generally north to south. The larger earthquakes in the area occur at the intersections of the two sets. It appears that seismicity of this part of Alaska may be conceptually represented by the grinding together of rigid blocks, with earthquakes occurring along their common boundaries and at the intersections where three or more blocks come in contact.
The author has identified the following significant results. The study of the ERTS-1 imagery of Alaska indicates the following: that areas of different topographic expression affecting the distribution and character of permafrost can be distinguished clearly; that on the Arctic North Slope, regional differences in the distribution and character of permafrost-related oriented thaw lakes can be observed; that the distribution of certain types of geologic materials having a significant effect on the character of permafrost can be delineated on a regional scale; and that the resolution of the imagery is adequate to identify large scale geologic hazards such as landslides, glacier-dammed lakes, aufeis fields, etc. The information concerning the distribution and character of permafrost and geologic hazards to the gained in accomplishing the objectives of this project will be an invaluable aid in solving engineering-geologic and environmental problems related to route and site selection for structures such as roads, railroads, pipelines, and large installations; to distribution of natural construction materials; and to construction and maintenance.
The author has identified the following significant results. A reconstituted, simulated color-infrared print, enlarged to a scale of 1:250,000, was used to make a vegetation map of a 3,110 sq km area just west of Fairbanks, Alaska. Information was traced from the print which comprised the southeastern part of ERTS-1 scene 1033-21011. A 1:1,000,000 scale color-infrared transparency of this scene, obtained from NASA, was used along side the print as an aid in recognizing colors, color intensities and blends, and mosaics of different colors. Color units on the transparency and print were identified according to vegetation types using NASA air photos, U.S. Forest Service air photos, and experience of the investigator. Five more or less pure colors were identified and associated with vegetation types. These colors were designated according to their appearances on the print: (1) orange for forest vegetation dominated by broad-leaved trees: (2) gray for forest vegetation dominated by needle-leaved trees; (3) violet for scrub vegetation; (4) light violet denoting herbaceous tundra vegetation; and (5) dull violet for muskeg vegetation. This study has shown, through close examinations of the NASA transparency, that much more detailed vegetation landscape, or ecosystem maps could be produced, if only spectral signatures could be consistently and reliably recognized and transferred to a map of suitable scale.
The author has identified the following significant results. A mosaic of ERTS-1 imagery for a portion of interior Alaska covering approximately 57,000 sq km has proved to be a valuable tool in identifying structural elements previously not recognized. Mapped faults are clearly recognizable and are found to be part of a larger system of faults and lineaments identified on the imagery. A previously unrecognized set of conjugate fractures imply regional compression in a NNW-SSE direction in agreement with known fault dislocations. Earthquakes have a marked tendency to occur at intersections of lineaments seen on the imagery.
The Bureau of Sport Fisheries and Wildlife ERTS experiment in Alaska attempts to yield information useful for three primary functions in the State. They are: (1) to test the feasibility of using ERTS data, in conjunction with aircraft acquired multispectral photography, to develop effective stratified sampling techniques, (2) to provide near real time assessment and evaluation of the quantity, quality, and distribution of waterfowl breeding habitat through frequent ERTS measurements of hydrologic, phenological and vegetational parameters, and (3) to provide basic mapping of vegetation and terrain in certain remote areas of the State for which little or no biological data now exist.
Areal patterns from field data and ERTS-1 imagery have shown a close relationship between geologic processes and the influence of sea ice along Alaska's northern coast, perhaps the nation's least known continental margin. Ice acts as; (1) a bottom-gouging agent; (2) an influence on water circulation; (3) a carrier of sediments; and (4) an influence on water types.
Cook Inlet is a large tide-dominated estuary in southern Alaska. Highly turbid streams enter the upper inlet, providing an excellent tracer for circulation in the lower inlet. MSS 4 and 5 images both can be used in this area to plot sediment and pollutant trajectories, areas of (probable) commercial fish concentration, and the entire circulation regime.