Loveland, A.M., 2010, Fracture evolution in a fold-and-thrust belt and the adjacent foreland basin: An example from the northeastern Brooks Range, Alaska: University of Alaska Fairbanks, M.S. thesis, xv, 168 p., illust., maps + DVD (4.75 in.) + map, on sheet 104 x 69 cm.
Fracture networks can enhance permeability in a reservoir, creating pathways for fluid migration. This study uses detailed surface and subsurface mapping, new and existing thermal and geochronologic data, as well as observations of fractures in outcrop to provide a framework for fracture development in the rangefront region along a surface to subsurface transect in the western part of the northeastern Brooks Range. Set 1 fractures formed prior to 45 Ma at >6 km depth, ahead of the Brooks Range mountain front in response to elevated pore fluid pressure and low differential stress. Set 2 fractures developed during the early stages of folding at a depth of ~7 km. Both Sets 1 and 2 developed synchronously with hydrocarbon generation and may have been early migration pathways, but were likely destroyed during advancement of the thrust belt. Late fracture Sets 3 and 4 formed at shallow depths in the absence of fluids and are probably related to the onset of uplift at ~25 Ma. These late sets postdate regional generation and migration, but may enhance reservoir permeability.
Theses and Dissertations