May 2013 - Rocky Mountain Association of Geologists

LEAD STORYNioFracture Initiative at the Universityof Wyoming: GIS Analysis of NaturalFractures in the Rocky MountainsEric A. Erslev 1 , Adjunct Professor; Laura Kennedy 2 , Research Scientist; Department of Geology andGeophysics, University of Wyoming, Laramie, WYIntroduction to NioFractureUnderstanding fractures in units that hostunconventional resources (e.g., the NiobraraFormation) is vital to predictingthe permeability and economicpotential of these tight reservoirs.Just understanding fracture timingis critical as the most recentfractures are more likely to beopen, and thus control hydrocarbonstorage and permeability conduits.Unfortunately, the complexPhanerozoic tectonic history of theRockies makes predicting fractureorientations and intensities difficultbecause an orogeny’s minor faultsand joints commonly extend farbeyond their major structures.For instance, minor fractures withNE-SW to E-W extension duringpost-Laramide rifting extend wellbeyond the Rio Grande Rift itself. In addition, localizedfracturing mechanisms like syn-Laramide arch collapseThe purpose of NioFractureis to integrate diversesources and representationsof minor fault (mode 2 and3 fractures) and joint (mode1 opening fractures) datain order to graphicallyportray the extent of RockyMountain fracture provinces.1eerslev@uwyo.edu2laura.eve.kennedy@gmail.com, now at Weatherford Laboratories, Golden, COand post-Laramide back-sliding on Laramide thrusts canrefract regional stress trajectories, greatly impactingfracture orientations.In 2012, the NioFractureinitiative received seed funding bythe School of Energy Resourcesat the University of Wyomingto develop a digital geographicinformation systems (GIS)database for fractures in theeastern Rockies. The purpose ofNioFracture is to integrate diversesources and representationsof minor fault (mode 2 and 3fractures) and joint (mode 1opening fractures) data in orderto graphically portray the extentof Rocky Mountain fractureprovinces. Initial datasets werelargely academic surface datafrom basin margins but it ishoped that the data coverage will be expanded to basininteriors with industry subsurface data.Continued on page 11 »OUTCROP9www.rmag.org