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- Creator:
- Bougher, Stephen W. and Roeten, Kali J.
- 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 derived temperatures and O plus CO2 densities are used to characterize the upper atmosphere dayside thermal and density structure. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of neutral densities have been obtained by the MAVEN team (e.g. Mahaffy et al. 2015; Bougher et al 2015; Elrod et al., 2017; 2021; Stone et al. 2018; Gupta et al., 2021). Measured neutral density 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 density and temperature distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for extreme Mars seasonal and solar cycle conditions were conducted for detailed comparisons with NGIMS derived temperatures and O/CO2 ratio distributions (Bougher et al. 2022). Extracted model densities and temperatures along the MAVEN inbound trajectory of each orbit path (between ~300 km and periapsis) are provided in this Deep Blue Data archive. Corresponding M-GITM heat balance terms are also provided in vertical 1-D tabulated formats. README files are included for each suite of 1-D "flythru" tables, 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, NASA MAVEN Mission, NGIMS instrument , and M-GITM numerical simulations
- Citation to related publication:
- Bougher, S. W., Benna, M., Elrod, M., Roeten, K., & Thiemann, E. (2023). MAVEN/NGIMS dayside exospheric temperatures over solar cycle and seasons: Role of dayside thermal balances in regulating temperatures. Journal of Geophysical Research: Planets, 128, e2022JE007475. https://doi.org/10.1029/2022JE007475
- Discipline:
- Science
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- Creator:
- Walsh, Lisa L
- Description:
- Stable isotope values of carbon (δ13C) and nitrogen (δ15N) from Virginia opossum (Didelphis virginiana) guard hairs were analyzed to evaluate the ecology and winter adaptations in opossums by Dr. Lisa L. Walsh as part of her Ph.D. thesis in the Ecology and Evolutionary Biology Department. The collection of stable isotope data took place from 2017 to 2019. Guard hair was processed at the University of Michigan and analyzed by the University of New Mexico Center for Stable Isotopes (UNM-CSI, USA). Captive and wild opossums were evaluated for evidence of biannual or incomplete biannual molting, a mammalian adaptation to harsh winters. Results suggest opossums do not exhibit either winter molting strategy and that guard hairs capture the opossum’s lifetime diet (Walsh and Tucker 2021). The stable isotope values were used to test the hypothesis that a Type A generalist’s niche is positively correlated with habitat heterogeneity and to evaluate which climate variables best explained isotope values. There was a positive correlation between isotopic niche size and habitat-diversity indexes (Walsh and Tucker 2020). The δ13C values from opossums in the Midwest and Northeast to test whether opossums rely on anthropogenic trash to survive extreme winters. There was no significant relationship between δ13C and winter variables, but there was a significant increase in variance of Midwest opossums’ δ13C after the 1970 corn agricultural boom (Walsh and Tucker 2023).
- Keyword:
- stable isotope, Virginia opossum, mesopredator, ecology, and mammal
- Citation to related publication:
- Walsh, L.L. and P.K. Tucker. 2020. Habitat heterogeneity is correlated with isotopic niche breadth across the range of a mammalian generalist mesopredator. Ecosphere, 11(12): e03314. https://doi.org/10.1002/ecs2.3314, Walsh, L.L. and P.K. Tucker. 2021. Stable isotope values suggest opossums (Didelphis virginiana) at their northern edge do not seasonally molt. Northeastern Naturalist, 28(1): 1-8. https://doi.org/10.1656/045.028.0101, and Walsh, L.L., and P.K. Tucker. 2023. Evaluating anthropogenic influence on a mesopredator: Opossum (Didelphis virginiana) isotope values influenced by corn agriculture more than urbanization. Canadian Journal of Zoology, 101: https://doi.org/10.1139/cjz-2021-0172.
- Discipline:
- Science
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- Creator:
- Jenkins, G. J. and Bougher, S. W.
- Description:
- In early 2019, the Mars Atmosphere and Volatile Evolution (MAVEN) mission underwent an ~2-month aerobraking campaign, during which time the spacecraft periapsis altitude was lowered from its nominal altitude range of 140-160 km to as low as ~123 km. Excluding spacecraft walk-in/out maneuvers, accelerometer measurements were made along 272 orbits with coverage spanning Ls 340-3°, latitudes ~5-54°S, longitudes 0-360°, and Local Solar Time (LST) ~22-17 hours. In this study, we perform a diagnostic analysis of the full aerobraking data set by fitting 4-harmonic waves to mass densities. We then study the variations of these waves as a function of latitude with an emphasis on those observed previously in Mars’ thermosphere by MAVEN and other missions. Additionally, we utilize data collected during the same time period from the Mars Reconnaissance Orbiter’s Mars Climate Sounder to study the vertical propagation of waves originating from the middle atmosphere. Key results indicate that normalized wave amplitudes decrease with latitude, and this is consistent with the latitudinal structure of a diurnal Kelvin mode. We also observe that waves imprinted from the middle atmosphere show normalized amplitude growth with increasing altitude. A complete summary of data sets, analysis methodology, and scientific results is given. The purpose of this study is to add to the body of knowledge surrounding Martian atmospheric wave features and to provide further constraints for future numerical modeling and subsequent tidal mode identification.
- Keyword:
- MAVEN, Mars Thermosphere, Accelerometer Data Set, Global Data Set, and Wave Analysis of Tides
- Citation to related publication:
- Jenkins, G. A., Bougher, S. W., Lugo, R., Tolson, R. H., Zurek, R. W., Baird, D., Steele, L., Kass, D., Withers, P. (2023), MAVEN Accelerometer Observations of Thermospheric Densities during Aerobraking and Deep Dip 2: Wave Features and Connections to Upward Propagating Thermal Tides, Journal of Geophysical Research: Planets, xx, xx.
- Discipline:
- Science
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- Creator:
- Title, Pascal O. and Bemmels, Jordan B.
- Description:
- The ENVIREM dataset v1.0 is a set of 16 climatic and 2 topographic variables that can be used in modeling species' distributions. The strengths of this dataset include their close ties to ecological processes, and their availability at a global scale, at several spatial resolutions, and for several time periods. The underlying temperature and precipitation data that went into their construction comes from the WorldClim dataset ( www.worldclim.org), and the solar radiation data comes from the Consortium for Spatial Information ( www.cgiar-csi.org). The data are compatible with and expand the set of variables from WorldClim v1.4 ( www.worldclim.org). For more information, please visit the project website: envirem.github.io
- Keyword:
- raster, species distribution modeling, and bioclimatic
- Citation to related publication:
- Title, P. O. and Bemmels, J. B. (2018), ENVIREM: an expanded set of bioclimatic and topographic variables increases flexibility and improves performance of ecological niche modeling. Ecography, 41: 291-307. http://doi.org/10.1111/ecog.02880
- Discipline:
- Science
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- Creator:
- Zhu, Jialei, Penner, Joyce E., Yu, Fangqun, Sillman, Sanford, Andreae, Meinrat O., and Coe, Hugh
- Description:
- The dataset contains the Fortran programs applied in the latest CESM/IMPACT model as well as the data created from this model, which are used in the referenced paper.
- Keyword:
- Organic nucleation and Radiative forcing
- Citation to related publication:
- Zhu, J. et al. Decrease in radiative forcing by organic aerosol nucleation, climate, and land use change. Nature Communications 10, 423 (24 January 2019). https://doi.org/10.1038/s41467-019-08407-7
- Discipline:
- Science
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- Creator:
- Johnson, JE and Molnar, PH
- Description:
- This IF compilation was assembled from the existing literature to understand if preservation biases affected the record of iron formations.
- Keyword:
- Archean ocean chemistry, temporal record of iron formations, and early Earth iron cycle
- Citation to related publication:
- Johnson, J. E., & Molnar, P. H. ( 2019). Widespread and persistent deposition of iron formations for two billion years. Geophysical Research Letters, 46, 3327– 3339. https://doi.org/10.1029/2019GL081970
- Discipline:
- Science
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- Creator:
- Crisp, Dakota N., Cheung, Warwick, Gliske, Stephen V., Lai, Alan, Freestone, Dean R., Grayden, David B., Cook, Mark J., and Stacey, William C.
- Description:
- The data and the scripts are to show that seizure onset dynamics and evoked responses change over the progression of epileptogenesis defined in this intrahippocampal tetanus toxin rat model. All tests explored in this study can be repeated with the data and scripts included in this repository. and Dataset citation: Crisp, D.N., Cheung, W., Gliske, S.V., Lai, A., Freestone, D.R., Grayden, D.B., Cook, MJ., Stacey, W.C. (2019). Epileptogenesis modulates spontaneous and responsive brain state dynamics [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/r6vg-9658
- Keyword:
- evoked response, stimulation, bifurcation, epilepsy, seizure, divergence, and dynamics
- Citation to related publication:
- Crisp, D. N., Cheung, W., Gliske, S. V., Lai, A., Freestone, D. R., Grayden, D. B., Cook, M. J., & Stacey, W. C. (2020). Quantifying epileptogenesis in rats with spontaneous and responsive brain state dynamics. Brain Communications, 2(1). https://doi.org/10.1093/braincomms/fcaa048
- Discipline:
- Science, Engineering, and Health Sciences
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- Creator:
- Nasser, Ahmad and Gumise, Wonder
- Description:
- The work on accelerating authenticated boot for embedded system resulted in designing an algorithm in python to perform the random address generation and cryptographic MAC calculation. The Sampled Boot schemes implemented in this package allow a significant reduction of the time needed to authenticate firmware images during startup, while still retaining a high degree of trust. This is particularly useful for automotive applications in which startup time constraints make secure boot a time prohibitive process. and Citation for this dataset: Nasser, A., Gumise, W. (2019). Authenticated Boot Acceleration Algorithm [Code and data]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/yeh1-1x17
- Keyword:
- Trusted Computing, IOT security, Embedded Security, and Cyber Physical Systems
- Citation to related publication:
- Nasser, A., Gumise, W., and Ma, D., "Accelerated Secure Boot for Real-Time Embedded Safety Systems," SAE Int. J. Transp. Cyber. & Privacy 2(1) : 35-48, 2019, https://doi.org/10.4271/11-02-01-0003
- Discipline:
- Science
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- Creator:
- Linyan, Xiang and Oleg, Zikanov
- Description:
- The Liquid Metal Battery (LMB), a promising energy-storage device that contains liquid-metal interior, is studied numerically in the paper. The metal pad roll instability was modeled based on the open-source CFD software, OpenFOAM. It's based on the solver for simulations of incompressible multiphase flows multiphaseInterFoam modified to include the electromagnetic fields and account for the sharp variations of the electrical conductivity.
- Keyword:
- Liquid metal battery, Interfacial waves, Instability, and OpenFOAM
- Citation to related publication:
- Linyan Xiang (相林言) and Oleg Zikanov, “Numerical simulation of rolling pad instability in cuboid liquid metal batteries,” Physics of Fluids, vol. 31, no. 12, p. 124104, 2019, https://doi.org/10.1063/1.5123170 and Oleg Zikanov, "Shallow water modeling of rolling pad instability in liquid metal batteries." Theoretical and Computational Fluid Dynamics, 32, 325–347, 2018, https://doi.org/10.1007/s00162-018-0456-2
- Discipline:
- Science
-
- Creator:
- Chen, Yang and Manchester, Ward IV
- Description:
- GOES_flare_list: contains a list of more than 10,000 flare events. The list has 6 columns, flare classification, active region number, date, start time end time, emission peak time, GOES_B_flare_list: contains time series data of SDO/HMI SHARP parameters for B class solar flares , GOES_MX_flare_list: contains time series data of SDO/HMI SHARP parameters for M and X class solar flares, SHARP_B_flare_data_300.hdf5 and SHARP_MX_flare_data_300.hdf5 files contain time series more than 20 physical variables derived from the SDO/HMI SHARP data files. These data are saved at a 12 minute cadence and are used to train the LSTM model., and B_HARPs_CNNencoded_part_xxx.hdf5 and M_X HARPs_CNNencoded_part_xxx.hdf5 include neural network encoded features derived from vector magnetogram images derived from the Solar Dynamics Observatory (SDO) Helioseismic and Magnetic Imager (HMI). These data files typically contains one or two sequences of magnetograms covering an active region for a period of 24h with a 1 hour cadence. We encode each magnetogram with frames of a fixed size of 8x16 with 512 channels.
- Keyword:
- machine learning, data science, and solar flare prediction
- Citation to related publication:
- Chen, Y., Manchester, W., Hero, A., Toth, G., DuFumier, B. Zhou, T., Wang, X., Zhu, H., Sun, Zeyu, Gombosi, T., Identifying Solar Flare Precursors Using Time Series of SDO/HMI Images and SHARP Parameters, Space Weather, 17, 1404–1426. https://doi.org/10.1029/2019SW002214 and Jiao, Z., Chen, Y., Manchester, W. (2020). Data for Solar Flare Intensity Prediction with Machine Learning Models [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/b07j-bj08
- Discipline:
- Engineering and Science
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- Creator:
- Tronson, Natalie C and Tchessalova, Daria
- Description:
- The main goal of this research was to identify potential molecular pathways that contribute to memory dysregulation and decline that persists long after illness or inflammation. We have previously established a subchronic immune challenge model that results in memory impairments months after the inflammatory challenge. This project aimed to determine whether memory impairments were accompanied by transcriptional dysregulation in memory related brain region (the hippocampus). These data show the differential gene expression as log2fold change (and p-value) in males and females 3 months after immune challenge (Supp Tables 1 and 2); after a subsequent immune challenge (Supp Tables 3 and 4); the differential regulation of genes in males and females (Supp Table 5); genes differentially expressed in the hippocampus of males and females at baseline (Supp Table 6) and the differential regulation of those genes in males and females after immune challenge (Supp Tables 7,8).
- Keyword:
- hippocampus, lipopolysaccharide, differential gene expression, RNA sequencing, neuroimmune, sex differences, learning and memory, and inflammation
- Citation to related publication:
- Tchessalova, D., & Tronson, N. C. (2019). Enduring and sex-specific changes in hippocampal gene expression after a subchronic immune challenge. BioRxiv, 566570. https://doi.org/10.1101/566570
- Discipline:
- Science and Health Sciences
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- Creator:
- Gebarski, Benjamin B. and Becker, Udo
- Description:
- Files are uploaded as crystallographic information files (.cif), the standard text file format for representing crystallographic information. These files contain the optimized molecular models for pentavalent plutonium incorporation reactions into/onto barite, anglesite, celestine, anhydrite, aragonite, and calcite host minerals.
- Keyword:
- actinide, quantum mechanics, molecular model, plutonium, incorporation, surface, radioactive, contamination, and nuclear waste
- Citation to related publication:
- Gebarski, B. B. and Becker, U. Quantum-Mechanical Determination of the Incorporation of Pentavalent Plutonium into Carbonate and Sulfate Minerals. (2019) Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2019.10.015
- Discipline:
- Science
-
- Creator:
- Horsley, Timothy J. and Sampson, Christina P.
- Description:
- The data (raw data, composite files [processed], and some images) can be read by the program TerraSurveyor. Version 3.0.34.10 of the software was used to create the composite files in this deposit. and The magnetometer data was the second step in a geophysical survey program that began with magnetic susceptibility survey of a portion of the Weedon Island Preserve in St. Petersburg, Florida. Geophysical survey was used to map human occupation of the study area and to guide subsequent archaeological excavations.
- Keyword:
- magnetometry, geophysical survey, remote sensing, Florida archaeology, and coastal archaeology
- Citation to related publication:
- Sampson, C. P. (2019) Safety Harbor at the Weeden Island Site: Late Pre-Columbian Craft, Community, and Complexity on Florida's Gulf Coast. PhD Dissertation, University of Michigan. and Sampson, Christina Perry and Timothy J. Horsley. Using Multi-Staged Magnetic Survey and Excavation to Assess Community Settlement Organization: A Case Study from the Central Peninsular Gulf Coast of Florida. Advances in Archaeological Practice. Cambridge University Press: 18 December 2019. https://doi.org/10.1017/aap.2019.45
- Discipline:
- Science and Social Sciences
-
- Creator:
- Liemohn, Michael W
- Description:
- The editorial decision process for the Journal of Geophysics Research Space Physics is assisted by over 1,000 scientists every year, providing over 3,000 reviews per year. These statistics are presented for the years 2013 through 2018, showing some fluctuations but, overall, consistency in the response of the space physics research community to requests to serve as manuscript reviewers. Over half of these reviews are submitted on time, and the average time to review actually dropped as the load increased. This is greatly appreciated and the community is to be commended and thanked for their willingness to help make this journal thrive and remain a premiere publication in the field.
- Keyword:
- Editorial and reviewer statistics
- Citation to related publication:
- Liemohn, M. W. (2020). Editorial: Multiyear analysis of JGR Space Physics reviewing statistics. Journal of Geophysical Research Space Physics, 125, e2019JA027719. https://doi.org/10.1029/2019JA027719
- Discipline:
- Science
-
- Creator:
- Arbic, Brian K. and Luecke, Conrad A.
- Description:
- The locations ("locs") files in this directory contain indices pointing to the locations in the CMA superset datafiles that were used in the Luecke et al. 2020 comparison of HYCOM and MITgcm model output to CMA observations.
- Keyword:
- Physical oceanography, Numerical modeling, Ocean modeling, Model/data comparisons, and Internal gravity waves
- Citation to related publication:
- Luecke, C. A., Arbic, B. K., Richman, J. G., Shriver, J. F., Alford, M. H., Ansong, J. K., Bassette, S. L., Buijsman, M. C., Menemenlis, D., Scott, R. B., Timko, P. G., Voet, G., Wallcraft, A. J., & Zamudio, L. (2020). Statistical Comparisons of Temperature Variance and Kinetic Energy in Global Ocean Models and Observations: Results From Mesoscale to Internal Wave Frequencies. Journal of Geophysical Research: Oceans, 125(5), e2019JC015306. https://doi.org/10.1029/2019JC015306
- Discipline:
- Science
-
- Creator:
- Chen, Yuxi
- Description:
- We use the MHD with embedded particle-in-cell model (MHD-EPIC) to study the Geospace Environment Modeling (GEM) dayside kinetic processes challenge event at 01:50-03:00 UT on 2015-11-18, when the magnetosphere was driven by a steady southward IMF. In the MHD-EPIC simulation, the dayside magnetopause is covered by a PIC code so that the dayside reconnection is properly handled. We compare the magnetic fields and the plasma profiles of the magnetopause crossing with the MMS3 spacecraft observations. Most variables match the observations well in the magnetosphere, in the magnetosheath, and also during the current sheet crossing. The MHD-EPIC simulation produces flux ropes, and we demonstrate that some magnetic field and plasma features observed by the MMS3 spacecraft can be reproduced by a flux rope crossing event. We use an algorithm to automatically identify the reconnection sites from the simulation results. It turns out that there are usually multiple X-lines at the magnetopause. By tracing the locations of the X-lines, we find the typical moving speed of the X-line endpoints is about 70~km/s, which is higher than but still comparable with the ground-based observations.
- Keyword:
- MHD, PIC, and simulation
- Citation to related publication:
- Chen, Y., Tóth, G., Hietala, H., Vines, S. K., Zou, Y., Nishimura, Y., Silveira, M. V. D., Guo, Z., Lin, Y., & Markidis, S. (2020). Magnetohydrodynamic With Embedded Particle-In-Cell Simulation of the Geospace Environment Modeling Dayside Kinetic Processes Challenge Event. Earth and Space Science, 7(11), e2020EA001331. https://doi.org/10.1029/2020EA001331 and Chen, Yuxi, et al. "Magnetohydrodynamic with embedded particle-in-cell simulation of the Geospace Environment Modeling dayside kinetic processes challenge event." arXiv preprint arXiv:2001.04563 (2020). https://arxiv.org/abs/2001.04563
- Discipline:
- Science
-
- Creator:
- Swiger, Brian M., Liemohn, Michael W., and Ganushkina, Natalia Y.
- Description:
- We sampled the near-Earth plasma sheet using data from the NASA Time History of Events and Macroscale Interactions During Substorms mission. For the observations of the plasma sheet, we used corresponding interplanetary observations using the OMNI database. We used these data to develop a data-driven model that predicts plasma sheet electron flux from upstream solar wind variations. The model output data are included in this work, along with code for analyzing the model performance and producing figures used in the related publication. and Data files are included in hdf5 and Python pickle binary formats; scripts included are set up for use of Python 3 to access and process the pickle binary format data.
- Keyword:
- neural network, plasma sheet, solar wind, machine learning, keV electron flux, deep learning, and space weather
- Citation to related publication:
- Swiger, B. M., Liemohn, M. W., & Ganushkina, N. Y. (2020). Improvement of Plasma Sheet Neural Network Accuracy With Inclusion of Physical Information. Frontiers in Astronomy and Space Sciences, 7. https://doi.org/10.3389/fspas.2020.00042
- Discipline:
- Science and Engineering
-
- Creator:
- James, David A. and Lokam, Nikhil
- Description:
- The object of this project is to provide researchers and students with a tool to allow them to develop an intuitive understanding of singular vectors and singular values. 2x2 matrices A with real entries map circles to ellipses; in particular, unit circles centered at the origin to ellipses centered at the origin. It is known that the points on the ellipse farthest from the origin correspond to the singular vectors of A. Users can use the GUI to enter matrices of their choice and explore to visually self-determine the singular vectors/values.
- Keyword:
- SVD, Singular Value Decomposition, Singular Vector, Singular Value, and Matrix
- Discipline:
- Science and Engineering
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Quantifying near-surface rock strength on a regional scale from hillslope stability models - dataset
- Creator:
- Townsend, Kirk F., Gallen, Sean F., and Clark, Marin K.
- Description:
- These datasets support the findings of Townsend et al. (2020). In this article, we quantify rock strength using two novel applications of hillslope stability models, resulting in estimates of cohesive and frictional strength at the spatial scale of small watersheds. We compare these results against the direct-shear test dataset here for validation of our approach. We find that cohesive strength is dependent on the original burial depth of the sedimentary rocks studied here. The low-temperature thermochronometry data was used to assess the magnitude of burial.
- Keyword:
- Thermochronology, Thermochronometry, Direct-Shear, Landslides, Rock Strength, Landscape Evolution, and Geomorphology
- Citation to related publication:
- Townsend, K.F., Gallen, S.F., & Clark, M.K., in press, Quantifying near-surface rock strength on a regional scale from hillslope stability models: Journal of Geophysical Research Earth Surface. https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JF005665
- Discipline:
- Science
-
- Creator:
- Boles, Austin H and van der Pluijm, Ben
- Description:
- This data was generated as a chapter in the dissertation of Austin Boles.
- Keyword:
- authigenic illite, hydrogen isotopes, and 40Ar/39Ar isotopic analysis
- Citation to related publication:
- Boles, A., & Pluijm, B. van der. (2020). Locally Derived, Meteoric Fluid Infiltration Was Responsible for Widespread Late Paleozoic Illite Authigenesis in the Appalachian Basin. Tectonics, 39(7), e2020TC006137. https://doi.org/10.1029/2020TC006137
- Discipline:
- Science