Abstract
The geology of Alaska has long been recognized as very complex. Recent paleomagnetic data, combined with paleogeographic reconstructions based on the concepts of plate tectonics, indicate that at least the southern parts of Alaska may be made up of a number of slivers of continental material rafted up along the western edge of North America.
If a model of this sort is real, the implications are far reaching. Thus, the first part of this survey explains in some detail the techniques and assumptions used, namely the paleomagnetic technique, the use of the geomagnetic field reversal pattern as seen in marine magnetic anomalies, the use of both local (Alaskan) and global seismicity patterns, and the concept of sea-mount chains generated by hot spots as indicators of past movement of the ocean floor.
By combining information derived from these different methods, an internally consistent picture of the development of the Alaska Peninsula and Gulf of Alaska has been assembled. This model involves the region that is now the Alaska Peninsula area, having been located at approximately the latitude of Oregon/california in early Mesozoic times, and looking much like Baja California looks today. Baja Alaska was then rafted north on the ancient Pacific plate, and rotated into its present position as a result of changes in the relative Pacific-North American plate motion.
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Stone, D.B. Plate tectonics, paleomagnetism and the tectonic history of the N.E. Pacific. Geophysical Surveys 3, 3–37 (1977). https://doi.org/10.1007/BF01449181
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DOI: https://doi.org/10.1007/BF01449181