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- Creator:
- Townsend, Kirk F., Clark, Marin K., and Niemi, Nathan A.
- Description:
- These datasets support the findings of Townsend et al. (in review) investigating the timing of faulting relative to changes in the orientation of the North American-Pacific plate boundary. Coeval with development of an oblique plate boundary segment (i.e. the “Big Bend” of the San Andreas fault), active shortening is inferred to have initiated at ~5 Ma in the Western Transverse Ranges (WTR). However, new low-temperature thermochronometric transects yield Miocene to Pleistocene apatite (U-Th-Sm)/He cooling ages and partially reset zircon (U-Th)/He ages. Inverse thermal modelling indicate that reverse faulting initiated as early as 10 Ma, several million years prior to our current understanding of the timing of the Big Bend. New and existing thermochronometry data delineate the WTR as the locus of rapid post-Miocene exhumation, and demonstrate that similar exhumation is not present in the broader region surrounding the Big Bend. We posit that reverse faulting is localized in the WTR because of a weak underlying lithosphere and predates the more recent geometric anomaly of the restraining bend in the transform margin.
- Keyword:
- Reverse faults, Fault initiation, Fault propagation, Low-temperature thermochronometry, Western Transverse Ranges, and San Andreas Fault
- Citation to related publication:
- Townsend, K. F., Clark, M. K., & Niemi, N. A., in review, Reverse faulting within a continental plate boundary transform system. Tectonics
- Discipline:
- Science
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- Creator:
- Auteri, Giorgia G., Knowles, L. Lacey, Marchán-Rivadeneira, Raquel M., and Olson, Deanna H.
- Description:
- This data was collected as part of a study to study population dynamics of coastal giant salamanders in Oregon. The study uses genetics to answer questions related to conservation concerns including population connectivity, sensitivity to habitat disturbances (such as logging and fires), and genetic diversity of populations.
- Keyword:
- salamander, Dicamptodon tenebrosus, conservation genetics, microsatellite , landscape genetics, population connectivity, and bottleneck
- Citation to related publication:
- Auteri, Giorgia G., M. Raquel Marchán-Rivadeneira, Deanna H. Olson, L. Lacey Knowles. Connectivity in coastal giant salamanders (Dicamptodon tenebrosus) shows no association with land-use, fire frequency, or river drainage but does not offset negative consequences of locally unstable population sizes. PLoS ONE. In review.
- Discipline:
- Science
-
- Creator:
- Brandt, Daniel, A. and Ridley, Aaron, J.
- Description:
- The research that produced this data focused on conducting a statistical comparison between horizontal winds modeled with GITM and those derived from the accelerometer aboard the GOCE satellite. The winds from GITM and GOCE were compared by constructing their respective probability densities under different levels of geomagnetic activity, and by distributing them as a function of geomagnetic activity, magnetic latitude, magnetic local time, day-of-the-year, and solar radio flux.
- Keyword:
- Thermosphere, GITM, GOCE, Neutral winds, and Thermospheric modeling
- Discipline:
- Science and Engineering
-
- Creator:
- Wu, Ziyou, Brunton, Steven L, and Revzen, Shai
- Description:
- These codes were produced as part of the Army Research Office Multi-University Research Initiative ARO MURI W911NF-17-1-0306 "From Data-Driven Operator Theoretic Schemes to Prediction, Inference, and Control of Systems" The code can be run using the runAll.sh shell script (in Linux and OS-X); code should work similarly under windows.
- Keyword:
- DMD, dimensionality reduction, dynamical systems, and nonlinear dynamics
- Discipline:
- Engineering and Science
-
- Creator:
- Revzen, Shai
- Description:
- This repository contains both the data and python3 code that reads this data and reproduces the relevant figures. The code depends on NumPy >1.17 and matplotlib >3.1 and was tested on python 3.8
- Keyword:
- locomotion, slipping, low Reynolds number, walking, and slithering
- Discipline:
- Science and Engineering
-
- Creator:
- Fuller, Jennifer, Rowan, Erin, Landgraf, Ava, Alofs, Karen, Foufopoulos, Johannes, and Gronewold, Andrew
- Description:
- This study investigates the rapid decline of black tern (Chlidonias niger) over eight years in one of Michigan’s largest colonies, Lake St. Clair. 1. Nesting Success Model: A multiple logistic regression with a binomial (logit-link) fit using the glm() function from the ‘stats’ package in R (55) to determine the influence of habitat and biological predictors on nesting survival. 2. ArcMap visualization of Nesting Success: To visualize the geographic extent of the habitat’s potential to predispose nests’ vulnerability, the coefficients and intercept from our selected GLM were applied to raster layers in ArcMap using the Raster Calculator Tool. 3. Population Change & Habitat Extent: To quantify sub-colony breeding pair population size and their response to changes in sub-colony habitat in the geospatial model, we applied a general linear mixed model (GLMM) using the lmer() function from the ‘lme4’ package in R (55). Predictor variables were chosen a priori, and included the area of open water, uninhabitable vegetation (NDVI>0.72), any habitable area, and area with >50% hatch success.
- Keyword:
- black terns, wetlands, ecology, climate change, lake levels, Great Lakes, waterbirds, ornithology, general linear model, geospatial, GIS, nesting success, avian, and breeding
- Citation to related publication:
- Fuller, J., Rowan, E., Landgraf, A., Alofs, K., Foufopoulos, J., Gronewold, A., (2021). Collapse of a Black Tern Colony (Chlidonias niger) as a Result of Climate Change Driven Lake-Level Extremes and Anthropogenic Habitat Alteration [Data set]. University of Michigan - Deep Blue. and Fuller, J., et al. (2021). Shorebird colony collapses under climate driven lake-level rise and anthropogenic stressors. Forthcoming.
- Discipline:
- Science
-
- Creator:
- Lynch, Erin and van der Pluijm, Ben
- Description:
- High-resolution, low-angle XRD analysis of oriented clay samples (.txt files) and TC/EA, Mass Spectronometric analysis of oxygen and hydrogen isotopes (.xslx files)
- Keyword:
- fault gouge and geofluids
- Citation to related publication:
- In submission
- Discipline:
- Science
-
- Creator:
- Hille, Madeline M., Clark, Marin K., Gronewold, Andrew D., West, A. Joshua, Zekkos, Dimitrios , and Chamlagain, Deepak
- Description:
- This dataset supports the findings of Hille et al. (2021, in review) in Geophysical Research Letters. In this article, we present a multivariate analysis of extreme storm events that occur during the Indian summer monsoon over the Himalayan Range in central Nepal. We resolve storm events at sub daily durations by merging NASA’s Global Precipitation Mission (GPM) Integrated Multi-satellitE Retrievals for GPM (IMERG) 30-minute, gridded 0.1x0.1-degree precipitation product with local rain gauges operated by the Nepal Department of Hydrology and Meteorology (DHM) and the International Centre for Integrated Mountain Development (ICIMOD). We quantify spatial variability in extreme rainfall by isolating storms over a specific intensity threshold and pairing a principal components analysis with a K-means clustering approach to group storms of similar characteristics. and We find that frequent and intense storms occur over the forefront of the central Himalayan range and coincide with a locus of monsoon-driven landslide density. This pattern agrees with observations of elevated annual precipitation volumes near the Himalayan physiographic transition from low to high relief (Bookhagen and Burbank, 2010), and is consistent with orographically-influenced rainfall over other mountain ranges (Marra et al., 2021). In addition to presenting novel methodology to quantifying storm variability, our results highlight the strong orographic effect on precipitation intensity and duration, as well as an association of shallow bedrock landsliding frequency with intense precipitation.
- Keyword:
- orographic rainfall, multivariate analysis, extreme rainfall events, and rainfall-triggered landslides
- Citation to related publication:
- Hille et al. (2021, in review). The orographic influence on storm variability, extreme rainfall characteristics and rainfall-triggered landsliding. Geophysical Research Letters. Forthcoming
- Discipline:
- Science
-
- Creator:
- Bougher, S. W. (CLaSP Department, University of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking systematic measurements of the densities and deriving temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface since late 2014. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. solar cycle, season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. For the current project, the inert light species helium is used to trace the circulation patterns and constrain wind magnitudes throughout the Mars thermosphere. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of helium densities have been obtained by the MAVEN team (e.g. Elrod et al., 2017; 2021; Gupta et al., 2021). Measured helium distributions are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides the needed context for understanding helium distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for the Mars four cardinal seasons (Ls = 0, 90, 180, 270, for Mars Year 33) were conducted for detailed comparisons with NGIMS helium and CO2 distributions (Gupta et al. 2021). The M-GITM datacubes used to extract these densities (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are also provided for each datacube, detailing the contents of each file. In addition, a general README file is provided that summarizes the inputs and outputs of the M-GITM code simulations for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- Mars, MAVEN Spacecraft Mission, Mars Thermosphere, Helium Density Distributions, and Neutral Gas and Ion Mass Spectrometer (NGIMS)
- Citation to related publication:
- Gupta, N., N. V. Rao, S. W. Bougher, and M. K. Elrod, Latitudinal and Seasonal Asymmetries of the Helium Bulge in the Martian Upper Atmosphere J. Geophys. Res., 126, XXXX-XXXX. doi:10.1002/2021JEXXXXXX
- Discipline:
- Engineering and Science
-
- Creator:
- Umaña, María Natalia and Arellano, Gabriel
- Description:
- The objective of this study was to examine the existence of congruent tree growth responses to different extreme climatic events –hurricanes and drought–affecting tropical wet forests.
- Keyword:
- Dendrometers , El Niño Southern Oscillation (ENSO), Hurricane Maria, Puerto Rico, and Tropical Forests
- Citation to related publication:
- Umaña, M.N.and Arellano G. In press. Legacy effects of drought on tree growth responses to hurricanes. Ecography. https://doi.org/10.1111/ecog.05803
- Discipline:
- Science