| Table 1. Proposed lateral ramps in the Appalachians and their
identifying characteristics.
[X, feature observed; N.O., change in fault frequency not yet observed; dash (--), feature not present; ?, igneous intrusion not certain] | |||||||
| Proposed lateral ramp name | Abrupt change in fold wavelength | Plungeouts of folds | Straight river trends | Geomorphic discontinuities in Blue Ridge or equivalent | Change in fault frequency at surface | Narrowing, interruption, or termination of Mesozoic basins | Seismic profile evidence |
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| Wilkes-Barre | X | X | Susquehanna River - upper reaches of Delaware River | -- | N.O. | -- | -- |
| Susquehanna | X | X | Susquehanna River | X | X | -- | X |
| Seven Mountains | -- | X | Middle of Juniata River | -- | X | -- | -- |
| Tyrone-Mount Union | X | X | Upper reaches of Juniata River | -- | X | -- | -- |
| Bedford | X | X | -- | X | X | -- | X |
| Pennsylvania-Maryland-West Virginia | X | X | Patuxent River | X | X | X | X |
| Mathias | X | X | Rappahannock River | X | X | X | X |
| Highland County | -- | X | James River | X | X | X | X |
| Lexington | X | X | Upper reaches of James River | X | X | X | -- |
| Roanoke | X | X | Roanoke River and northwest arm of Smith Mountain Lake | X | X | X | -- |
| Blacksburg | -- | X | -- | -- | X | -- | -- |
| New River | -- | X | New River | X | X | X | -- |
| Pulaski | -- | X | -- | -- | X | -- | -- |
| Johnson City | -- | X | -- | X | X | X | -- |
| Kingsport | -- | ;X | -- | X | X | X | -- |
| Knoxville | X | X | -- | X | N.O. | -- | -- |
| Fontana Lake | -- | X | Tennessee River | X | N.O. | -- | -- |
| Rising Fawn* | -- | X | -- | -- | N.O. | -- | -- |
| Calhoun | -- | X | -- | X | N.O. | -- | -- |
| Springville | -- | X | -- | -- | N.O. | -- | -- |
| Piedmont | -- | X | -- | -- | N.O. | -- | -- |
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| Table 1 -- Continued. Proposed lateral ramps in the Appalachians and their identifying characteristics.
[X, feature observed; N.O., change in fault frequency not yet observed; dash (--), feature not present; ?, igneous intrusion not certain] | ||||||||||
| Proposed lateral ramp name | Modern earthquakes (1628 to present) | Giant landslides (Schultz and Southworth, 1989) | Tectonic windows | Abrupt change in thickness of facies | Coarse pebble conglomerates | Igneous intrusions | Major elements crossing Precambrian block | High frequency of mineral deposits | Geophysical evidence | |
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| Wilkes-Barre | X (9) | -- | X | X | X | -- | -- | -- | -- | |
| Susquehanna | X (11) | -- | X | X | X | X | -- | X | -- | |
| Seven Mountains | -- | X | -- | -- | -- | -- | -- | -- | -- | |
| Tyrone-Mount Union | X (2) | -- | X | -- | -- | -- | -- | -- | X | |
| Bedford | -- | -- | -- | X | -- | -- | -- | -- | X | |
| Pennsylvania-Maryland-West Virginia | X (5) | X | -- | X | X | X | -- | -- | -- | |
| Mathias | X (7) | -- | -- | X | -- | ? | -- | X | -- | |
| Highland County | X (22) | -- | -- | -- | -- | X | -- | -- | X | |
| Lexington | X (1) | -- | -- | -- | -- | -- | -- | -- | -- | |
| Roanoke | X (5) | X | X | X | X | -- | -- | -- | X | |
| Blacksburg | X (6) | X | X | -- | -- | -- | -- | -- | -- | |
| New River | X (7) | X | X | X | -- | X | -- | -- | -- | |
| Pulaski | X (11) | X | X | -- | X | -- | -- | -- | -- | |
| Johnson City | X (11) | -- | X | -- | -- | X | -- | -- | -- | |
| Kingsport | X (10) | X | X | -- | -- | -- | X | -- | -- | |
| Knoxville | X (17) | -- | X | -- | -- | -- | -- | -- | -- | |
| Fontana Lake | X (7) | -- | X | -- | -- | -- | -- | -- | -- | |
| Rising Fawn* | X (10) | -- | X | X | -- | X | -- | X | X | |
| Calhoun | X (8) | -- | X | -- | --. | -- | X | -- | -- | |
| Springville | X (3) | -- | X | -- | -- | -- | -- | -- | -- | |
| Piedmont | X (7) | -- | X | -- | -- | -- | X | -- | -- | |
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