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Southeastern California is known for complex fault networks that accommodate strain from Pacific-North American plate convergence. The 250-km-long, left-lateral Garlock fault is integral to this system, yet its overall kinematic role within the plate boundary and relationship with faults of the Eastern California shear zone/Walker Lane belt remain poorly understood. A key area that has not been adequately studied is a 15-km stretch of the eastern Garlock fault, at its intersections with the right-lateral Brown Mountain fault and left-lateral Owl Lake fault. This segment of the fault lies within the China Lake Naval Air Weapons Station and U.S. Fort Irwin boundaries, which have restrictions on civilian access and portions of which contain unexploded ordnance, making them unsuitable and unsafe for field investigations. The purpose of this project is to use a combination of high-resolution LiDAR topographic data, remotely sensed imagery, and published geochronology data to map and establish the ages of faulted landforms along this portion of the eastern Garlock fault. The inaccessibility of this area makes it ideal for the application of remote-sensing techniques. A range of surface analysis techniques were used to differentiate and map Quaternary units in the study area. Geomorphic surface properties were determined from physiographic roughness and surface reflectance data, established from analysis of LiDAR, radar backscatter, and visual-near and short-wave infrared multispectral and hyperspectral reflectance datasets. The ages of faulted landforms were established using two approaches: (1) fault scarp and terrace riser degradation analysis and (2) a surface property-age model that links remotely sensed surface properties to new and published ages of alluvial surfaces in the region. A final goal of the study was to determine the slip rate along this segment of the Garlock fault and other faults in the map area. To accomplish this, offset landforms, such as terrace risers and channels, were analyzed in the context of the new age determinations. The results will be compared to published slip rate estimates for the region in order to better understand the Garlock fault's role within the plate boundary and how plate boundary strain is being accommodated in such an intraplate setting. 

A bstract We study a renormalizable model of Dirac fermion dark matter (DM) that communicates with the Standard Model (SM) through a pair of mediators — one scalar, one fermion — in the representation ( 6 , 1 , $$ \frac{4}{3} $$ 4 3 ) of the SM gauge group SU(3) c × SU(2) L × U(1) Y . While such assignments preclude direct coupling of the dark matter to the Standard Model at tree level, we examine the many effective operators generated at one-loop order when the mediators are heavy, and find that they are often phenomenologically relevant. We reinterpret dijet and pair-produced resonance and jets + $$ {E}_{\mathrm{T}}^{\mathrm{miss}} $$ E T miss searches at the Large Hadron Collider (LHC) in order to constrain the mediator sector, and we examine an array of DM constraints ranging from the observed relic density Ω χ $$ {h}_{\mathrm{Planck}}^2 $$ h Planck 2 to indirect and direct searches for dark matter. Tree-level annihilation, available for DM masses starting at the TeV scale, is required in order to produce Ω χ $$ {h}_{\mathrm{Planck}}^2 $$ h Planck 2 through freeze-out, but loops — led by the dimension-five DM magnetic dipole moment — are nonetheless able to produce signals large enough to be constrained, particularly by the XENON1T experiment. In some benchmarks, we find a fair amount of parameter space left open by experiment and compatible with freeze-out. In other scenarios, however, the open space is quite small, suggesting a need for further model-building and/or non-standard cosmologies.