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The goal of this study is to map and characterize Quaternary faults in southern Dixie Valley for the Department of the Navy Geothermal Program Office’s NAS Fallon Geothermal Exploration Project. We will use this information to better characterize the regional structure and geothermal resource potential of the area, with a focus on determining the structural controls for two known geothermal anomalies. Previous structural investigations at other geothermal sites in Nevada have shown that Quaternary faults provide the best potential for geothermal fluid flow. Information on the structural characteristics, such as slip sense and relative age, will be synthesized into a structural kinematic model. The resulting structural kinematic model will help us identify the slip and dilation tendencies of the faults in southern Dixie Valley. This model will for allow a better understanding of what faults control these two geothermal anomalies and aid in exploration and selection of drilling targets. In order to detect and characterize young faults, high resolution LiDAR and 1:12,000-scale low-sun-angle (LSA) aerial photography was acquired for the NAS Fallon study area. The LSA photos were flown during early morning, when the sun angle ranged between 10-25°. Slopeshades and hillshades using low sun angles (25-45°) were generated using LiDAR for fault detection. Elevation change and tonal lineaments were used to define possible faults in both the LiDAR and LSA photo data sets. The LiDAR and LSA photo analysis has identified a large number of previously unmapped faults. Field investigations will determine slip sense and age of these newly mapped faults. Preliminary structural analysis using the newly mapped faults, in conjunction with shallow 2-meter temperature surveys, suggests that the two known geothermal temperature anomalies occur in complex structural settings. A possible 3rd low temperature anomaly was also detected, but will require further investigation. Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Erica L. Helton1, 2, John W. Bell3, Patricia H. Cashman1, 2, Michael Lazaro4, Steve Alm4 1Department of Geological Sciences and Engineering, University of Nevada, Reno 2Great Basin Center for Geothermal Energy 3Nevada Bureau of Mines and Geology, University of Nevada, Reno 4Department of the Navy Geothermal Program Office Figure 1. Location map of the general project area in southern Dixie Valley. Only Quaternary fault traces have been mapped. Solid black lines represent well located faults, dashed black lines represent approximately located faults, and dotted black lines represent faults that are inferred. Lines highlighted in red are faults that experienced 1954 rupture (Caskey et al., 1996). Pink dashed lines indicate lineaments seen in aerial photography and LiDAR. LMF: Louderback Mountains Fault. LPCFZ: La Plata Canyon Fault Zone. MVFZ: Mid-Valley Fault Zone. The red star represents the approximate location of the Pirouette Mountain geothermal anomaly. The orange star represents the approximate location of the Elevenmile Canyon geothermal anomaly. Red numbered rectangles indicate areas of