Nimbus IV view of the major structural features of Alaska

E. H. Lathram

doi:10.1126/science.175.4029.1423

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Nimbus IV view of the major structural features of Alaska

E. H. Lathram

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Abstract

Notwithstanding the relatively low degree of ground resolution, many of the major structural features of Alaska can be identified on the Nimbus IV IDCS image, exposed at an altitude of 600 nautical miles (1100 km). In addition, linears of regional extent that may be structurally controlled can be seen, many of which have not yet been recognized in surface mapping. The synoptic view provided by the image brings into focus an orthogonal set of fractures trending north-northeast and east-southeast and not heretofore apparent in regional maps of Alaska. This orthogonal fracture set may reflect a conjugate set of fractures within the crust, which has exerted significant control over the geologic history of the state. Increased resolution in other images from space platforms, such as the resolution of 200 to 650 feet (60 to 200 m) planned for the satellite television cameras of the ERTS program, will permit the discernment of finer detail and a greater accuracy in identifying and locating geologic features.

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Source-reported bounding extent: 50.98609893339354° to 71.45515260247822° latitude; -178.9453125° to -129.97169494628906° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

E. H. Lathram. 1972. Nimbus IV view of the major structural features of Alaska. https://doi.org/10.1126/science.175.4029.1423

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