PHOTOLINEAR ANALYSIS OF THE TRIASSIC SANFORD SUBBASIN, NORTH CAROLINA

A Brevard College Senior Project using photolinear analysis of the Triassic geology in the Sanford Subbasin to the north and east of Sanford, North Carolina was undertaken to identify prominent linear features and linear feature intersections present in the Triassic basins straddling central North Carolina. Using a combination of black-and-white and color aerial photos, LANDSAT and LiDAR imagery, and USGS topographic maps, linear features were plotted on an aerial photo base map constructed from USGS air photos downloaded from http://map-pass.mytopo.com. More than 400 photos were mosaicked to create the base map, using Adobe Illustrator, at a scale of 1:25,000, covering an area of approximately 12,000 km². Features shorter than 500 m are not plotted on the map unless they align with other linear features.

Although this map is subjective and biased by the type of photo imagery/photos used, interpreter experience, and a variety of other factors, the resulting map identified nearly all known Triassic faults but also revealed hundreds of other significant linear features and intersections. This type of mapping provides a baseline data set that can be constructed for all regions of the state that are targeted for hydrocarbon exploration using hydraulic fracturing (fracking). Levels of natural methane emissions along these features can be monitored prior to drilling in order to quantify any emissions detected after fracking is completed.