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Identifying instruments and surveys to address geoscience education research (GER) questions is among the high-ranked needs in a 2016 survey of the GER community (St. John et al., 2016). The purpose of this study was to develop and validate a student-centered assessment instrument to measure course experience in a general education integrated science course. A one-shot case study of pre-experimental design (Creswell, 2009, 2014) was used to understand student experiences in a large-enrollment course with digital content integration, including out-of-class video, online presentations, and warm-up questions, as well as in-class video paired with discussion and small group activities. In two sections taught by the same geoscientist, 209 students accessed course content in an online learning management system prior to classroom instruction. We adapted the 36-item Course Experience Questionnaire (CEQ; Wilson et al., 1997) to a Web-based survey. We conducted statistical analysis on the CEQ responses, including item factor analysis, examination of communalities and measures of association, confirmatory factor analysis, and reliability and stability testing through bootstrap resampling. The statistical analyses indicate that the results in this study are comparable to those from other cultural contexts and subject areas. Given the moderate fit of the model and reasonably stable results, we propose that the core indicators of the CEQ constructs, including Appropriate Workload, Clear Goals and Standards, Generic Skills, Good Teaching, and Emphasis on Independence are sufficient to assess students' course experiences in general education science settings. These results provided moderately to strongly valid information that can help instructors in designing their technology-integrated classes, although further study with a larger sample population would be beneficial. From this study we conclude that students' perceptions of their course experiences are closely related to their development of problem-solving and analytical skills, clear course expectations to direct their own study plans, their preference for a motivating instructor, the opportunity to have a variety of learning choices, and their workload. We propose the use of a 25-item version of the CEQ that is appropriate for formative assessment in discipline-specific STEM introductory classes, including geoscience classes.

We examine upper-mantle seismic anisotropy beneath the cordillera and craton of north-western Canada using the multi-event station averages of shear-wave splitting of SKS, SKKS, and sSKS phases recorded during the Canadian Northwest Experiment (CANOE). Splitting times derived from multi-event averaging at each station range from 0 to 1.4 s, with an array average of ~0.65 s. Over broad portions of the array, fast directions are coherent and roughly consistent with the direction of absolute plate motion in a hotspot reference frame, suggesting that coherent asthenospheric fabric underlies the plate in much of the region. Within this broad framework, fast directions and splitting times show marked variability over length scales of 50-200 km, and are generally correlated with surface and/or crustal tectonics. Anomalous splitting is observed across an ancient suture within the cratonic lithosphere, apparently associated with complex dipping fabric produced during continental assembly. The deformation front of the Canadian Rockies correlates with a significant change in splitting behavior, consistent with the front range demarking the craton-cordillera transition within the mantle. Splitting times are small across much of the cordillera, indicating that lithospheric and/or asthenospheric fabric is weaker or less coherent than beneath the craton. In the western cordillera, fast directions rotate abruptly to parallel the plate boundary, implying that fabric associated with plate-boundary deformation extends ~200 km into the North American continent. doi: 10.1130/G31120.1

The article offers information on the development of science inquiry learning and academic language and literacy with science notebooks among K-3 learners. Topics discussed include the use and benefits of science notebooks in recording students' inquiry journeys on science processes and concepts, the significance of academic language, and the use of illustrative rubric to determine academic language and literacy development in notebooks.

In this study, we compare two methods commonly used to image mantle interfaces: teleseismic receiver functions and ScS reverberations. The ScS method benefits from the use of absolute travel times and therefore better constrains discontinuity depths, while receiver functions benefit from better event coverage and high-frequency resolution. We apply these methods to a permanent station located in the Hawaiian Islands and present a proof of concept for the joint application of the two techniques. First, ScS reverberations are used to assess mantle discontinuity depths and whole-mantle travel times. Based on this preliminary model, receiver functions are subsequently used to refine both lateral and vertical discontinuity structure. The validity of the combined results is assessed by benchmarking the receiver functions with a local tomographic velocity model (Wolfe et al., 2009). [ABSTRACT FROM AUTHOR]

Abstract: We examine the upper mantle and transition zone beneath the western Pacific using multiple ScS reverberations. A low-velocity zone (LVZ) is found above the 410-km discontinuity oceanward of the subducting Honshu slab at an average depth of 356km, with a thickness that ranges from 50 to 75km assuming the LVZ continues to the 410-km discontinuity, which is locally elevated. The low-velocity region is evident in previous tomographic studies, and our results suggest that the anomaly is best explained by a layer of partial melt. The layer may be entrained from above by subduction or produced in situ by the combined effects of water and temperature. A self-consistent model that explains local P-wave velocities (Obayashi, M., Sugioka, H., Yoshimitsu, J., Fukao, Y., 2006. High temperature anomalies oceanward of subducting slabs at the 410-km discontinuity. Earth and Planetary Science Letters 243, 149–158) and our observations calls for a maximum temperature anomaly of ∼150°C and a resulting maximum olivine water content after melting of 0.100wt. %. [Copyright &y& Elsevier]