Elsevier

Tectonophysics

Volume 305, Issues 1–3, 10 May 1999, Pages 225-233
Tectonophysics

Transcontinental Arch — a pattern formed by rejuvenation of local features across central North America

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Abstract

The Transcontinental Arch has been described by many authors as a feature having significant tectonic influence during the Phanerozoic, although the location, magnitude, and even the timing defining the arch vary greatly among authors. The general trend usually suggested for the Transcontinental Arch is northeast–southwest across the western midcontinent of North America. A series of isopachous and paleogeologic maps was compiled for this study that defines a number of smaller tectonic features — commonly trending northwest–southeast. Six persistent highs and six persistent lows (or sags) are defined that are largely basement controlled and were rejuvenated at various times during the Phanerozoic. These smaller northwest-trending features, when taken collectively and enhanced by the relative downwarping of the adjacent Williston and Anadarko basins, create a platform-like feature — the Transcontinental Arch of the literature. The concept of a Transcontinental Arch is an important reference trend in the geologic history of North America. In both regional and local studies, however, the smaller-scale, transverse features may have had significant control on both tectonic patterns and depositional influence.

Section snippets

Introduction and background

A major North American structural element, `the backbone of the continent', was mentioned by Keith (1928)in his presidential address to the Geological Society of America. He described a sinuous trend extending from central Canada into central Mexico, which he said “has persisted through all the ages back to the beginning of the Paleozoic”. The focus of this paper will be on this continent-scale feature which, although defined about 70 years ago, continues to be somewhat mythical in concept (

Phanerozoic history

A series of maps illustrate zero edges and major thickness patterns for segments of the geologic record (Fig. 2Fig. 3). Primary data sources used in the assembly of the maps were atlases and compilations of regional stratigraphy such as those by Ham and Wilson (1967), Carlson (1970), Mallory (1972), Cook and Bally (1975), Peterson (1986), Sloss (1988), Hoffman (1989)and Bally and Palmer (1989). The compilations illustrate current thickness and not the original depositional boundaries but the

Conclusion

Fig. 8 illustrates the general boundaries of a composite transcontinental feature. The name, Transcontinental Arch, has traditional acceptance and, in broad perspective, it does give the appearance of a southwest–northeast tectonic feature. Upon examination of the geological record, however, there is no dominant structural trend in this direction nor is there consistent arching within Phanerozoic sediments. As a composite feature, the Transcontinental trend appears as a broad, discontinuous

References (17)

  • Bally, A.W., Palmer, A.R. (Eds.), 1989. The Geology of North America — An Overview. Geol. Soc. Am., Boulder, Colo., A,...
  • Carlson, M.P., 1970. Distribution and subdivision of Precambrian and lower and middle Paleozoic rocks in the subsurface...
  • M.P. Carlson

    Transcontinental arch — backbone of North America

    28th Int. Geol. Congr. Abstr.

    (1989)
  • Carlson, M.P., 1993. Transcontinental Arch of North America — backbone or skeleton? Geol. Soc. Am. Abstr. Prog. 25 (6),...
  • J. Chronic et al.

    Lower Paleozoic rocks in diatremes, southern Wyoming and northern Colorado

    Geol. Soc. Am. Bull.

    (1969)
  • Cook, T.D., Bally, A.W. (Eds.), 1975. Stratigraphic Atlas of North and Central America. Princeton University Press,...
  • Eardley, A.J., 1951. Structural Geology of North America. Harper, New York, N.Y., 624...
  • J.K. Geslin

    Distal Ancestral Rocky Mountains tectonism: evolution of the Pennsylvanian–Permian Oquirrh–Wood River basin, southern Idaho

    Geol. Soc. Am. Bull.

    (1998)
There are more references available in the full text version of this article.

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