THRUST FAULT IN HANGMAN VALLEY: A POSSIBLE SPLAY OF THE SPOKANE AND LATAH FAULT SYSTEMS

South of Spokane, Washington located along Hangman Creek is a thrust fault exposed by a cut bank. Plunge and trend of the exposed fault were utilized to determine the apparent dip of the fault. In light of the recently discovered Spokane fault as well as the possible Latah fault, awareness of seismic hazards in the densely populated area of Spokane is elevated. This investigation includes interpretation of the fault along Hangman Creek and its relationship to the Spokane fault and Latah fault systems. Photographs of the exposed fault, contributed by Eugene Kiver, along with LiDAR, provided by Spokane County, are used to estimate the length of shortening, offset and the degree and direction of apparent dip for the ramp. Apparent dip is applied in calculating several possibilities for strike and dip of the fault. Data from the calculations are compared to both the Spokane fault and the Latah fault. Determination of connection between the Spokane Fault and the Latah fault and the Hangman Creek thrust fault is derived from the possible geometric orientations of the fault-bend-fold. This thrust fault along Hangman Creek is a possible splay off the proposed Latah fault, potentially similar to the newly discovered Spokane fault.