Document Type
Thesis
Abstract
The tectonic processes of supercontinent breakup create rift structures that are often preserved along the passive margin of continents. The resultant structures and rocks are the foundation from which collisional orogenic structures are eventually created. At Sugar Hollow, 15km northwest of Charlottesville, Virginia, ancient lapetan rift structures are preserved on the eastern margin of Laurentia in the Virginia Blue Ridge. This location preserves a ~10km? eastwardthickening graben complex consisting of 8 originally-normal faults that reaches a maximum thickness of ~300m. Some of the 8 faults were reactivated past the null point during the Paleozoic—producing apparent thrust geometry. To better understand the original structures that accommodated the opening of the lapetan Ocean at the close of the Neoproterozoic, the basin was restored to its post-rift state using Midland Valley’s Move software. During this process, layers were unfolded and fault blocks were restored to their maximum extensional state, revealing ~12% shortening. However, penetrative ductile deformation was not accounted for during this restoration. Therefore, strain and vorticity analysis were used to better understand the intensity and geometry of ductile deformation across the basin. Using this data, a fully restored 3D model of the Sugar Hollow basin was created. This model revealed additional shortening of ~13%, suggesting that penetrative strain may be at least as important of a restoration consideration as faulting and folding. Consequently, strain and vorticity analysis should be integrated into cross section restoration whenever possible.
Date Awarded
2010
Department
Geology
Advisor 1
Christopher M. Bailey
Recommended Citation
Laskowski, Andrew K., "3D Restoration of the Sugar Hallow Rift Basin, Blue Ridge, Virginia" (2010). Geology Senior Theses. William & Mary. Paper 232.
https://scholarworks.wm.edu/geologyseniors/232
