The hierarchical plate hypothesis of geologic history includes the concept that the North American continental block has been circling the Pacific Basin plate in a counterclockwise sense and rotating in the same sense, with an approximate period of 10⁹ years. Implications inherent in the hypothesis, for comparison with the actual history of North America during its latest 10⁹ years of development, include the following.

1. Climate:
Continental glaciation about 10⁹ years ago; warming during late Precambrian. Tropical during Paleozoic; much carbonate deposition; widespread coal in late Paleozoic. Cooling during Mesozoic and Cenozoic, climaxing in new glaciation.

2. Appalachian Mountains:
Left lateral movement plus compression during Paleozoic. Right lateral movement plus tension during Mesozoic and Cenozoic.

3. Carribbean:
Developed initially about end of Paleozoic--beginning of Mesozoic. Strike-slip margins on north and south.

4. Gulf of Mexico:
Tensional feature; developed initially about end of Paleozoic-beginning of Mesozoic.

5. Sedimentation:
Major drainage toward south (ambient coordinates), producing very large sediment volumes in Gulf of Mexico.

6. Depocenter:
Shifting location toward north and east, from Texas into Louisiana, due to continental rotation during post-Paleozoic.

7. Stream patterns:
Reorientation, due to continental rotation, through Mesozoic and Cenozoic in clockwise sense for first-order drainage, counter-clockwise for second-order drainage in mid-continent area; much piracy.

8. Eastern and western margins:
Lateral shrinking subsidence, and formation of north-south grabens, during post-Paleozoic.

9. Diapirism:
Dikes, plugs, volcanoes, and salt domes (where salt was available) along western, southern, and eastern margins, during Mesozoic and Cenozoic.

10. Probable geosyncline:
Short-lived, late Paleozoic age; near southern edge of continent; orientation now northeast-southwest.

These predictions compare favorably with the actual history of the continent.

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