The Midcontinent Rift System
نویسنده
چکیده
One of the most prominent features on gravity and aeromagnetic maps of the United States is a series of major, generally linear anomalies that extend from central Kansas to Lake Superior and then turn southward into central Michigan (Figures 1, 2). This system of anomalies clearly reflects major geological features, and as such it must represent a very significant episode in the history of the North American continental lithosphere. The geologic features associated with these anomalies, particularly axial basins filled with basalt and immature clastic rocks along with evidence of crustal extension, indicate that the episode was probably one of incipient rifting.
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