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Documenting the geometry, magnitude and kinematics of ductile deformation provides important insights into the structural and rheological evolution of continental lithosphere. The Northern Snake Range metamorphic core complex in eastern Nevada provides an exceptional opportunity to investigate the geometry and magnitude of ductile strain during high-magnitude continental extension. Decades of mapping-based research has provided exceptional stratigraphic context for the footwall of the low-angle, top-down-to-ESE, normal-sense Northern Snake Range dècollement (NSRD). In the northern part of the range, Middle-Late Cambrian marble units in the NSRD footwall, which have a cumulative stratigraphic thickness of 1107 ± 107 m in adjacent ranges, were ductilely thinned during Late Eocene-Late Oligocene extension. From west to east across the range, these rocks have been thinned from 869-935-m-thick (15-21% structural thinning) to 54-88 m-thick (92-95% structural thinning) across a 12 km lineation-parallel distance. Ductile extensional strain was accompanied by the development of pervasive linear-planar fabrics and produced megaboudins of calcareous schist units that are ~100-500-m-long, ~15-25-m-thick, and separated by as much as ~1000 m. The magnitude of subhorizontal, ESE-directed, lineation-parallel ductile extension increases eastward across the range from 24 ± 21% to 1226 ± 256%, and total ductile extension across the range is 12.1 ± 2.2 km (167 ± 31%). Quartz recrystallization microstructures and published calcite-dolomite thermometry indicate deformation temperatures of ~400-550 °C during initial Late Eocene-Late Oligocene ductile extensional shearing. NSRD footwall rocks in the eastern part of the range experienced a longer ductile extensional strain history and a prolonged residence time at higher temperatures compared to the western part of the range. This was facilitated by the progressive eastward migration of denudation-related cooling and was likely enhanced by shear heating that scaled eastward with strain magnitude, and/or a possible eastward increase in burial depth. These factors promoted the development of the extreme ductile strain gradient in the NSRD footwall across the Northern Snake Range. 

We study the problem of experiment planning with function approximation in contextual bandit problems. In settings where there is a significant overhead to deploying adaptive algorithms—for example, when the execution of the data collection policies is required to be distributed, or a human in the loop is needed to implement these policies—producing in advance a set of policies for data collection is paramount. We study the setting where a large dataset of contexts but not rewards is available and may be used by the learner to design an effective data collection strategy. Although when rewards are linear this problem has been well studied [53], results are still missing for more complex reward models. In this work we propose two experiment planning strategies compatible with function approximation. The first is an eluder planning and sampling procedure that can recover optimality guarantees depending on the eluder dimension [42] of the reward function class. For the second, we show that a uniform sampler achieves competitive optimality rates in the setting where the number of actions is small. We finalize our results introducing a statistical gap fleshing out the fundamental differences between planning and adaptive learning and provide results for planning with model selection. 

Using data from a 5-year ongoing study of early career Latine engineers, we report scores on sociocultural variables (i.e., acculturation; enculturation) and work outcomes (i.e., goal progress; work satisfaction; turnover intentions, work satisfaction, and life satisfaction). We examine differences in scores across Latine engineers based on gender, parental status, and characteristics of workers in the employer’s organization. The findings may point to workplace factors that can impact the retention of Latine engineers.