Joel B Sankey Joshua J Caster Elizabeth M Prior Laura E Durning Nathaniel Bransky 20250307 vector data Flagstaff, AZ U.S. Geological Survey Additional information about Originators: Sankey, Joel B, https://orcid.org/0000-0003-3150-4992; Caster, Joshua J, https://orcid.org/0000-0002-2858-1228; Prior, Elizabeth M, https://orcid.org/0000-0001-7069-160X; Durning, Laura E, https://orcid.org/0000-0003-3282-2458; Bransky, Nathaniel, https://orcid.org/0000-0003-3113-7491 https://doi.org/10.5066/P1Y6N5AC These data were compiled to show where significant river-sourced aeolian sediment deposits are present along the Colorado River downstream of Glen Canyon Dam in the Grand Canyon from Lee’s Ferry to the Diamond Creek confluence located 225 miles downstream. These deposits represent 118 active aeolian dunefields and were created by the Grand Canyon Monitoring & Research Center using field data and 20-cm pixel resolution, four spectral band imagery collected in 2013 (Durning and others, 2016) and validated using field observations and oblique photography. River-sourced sediment associated with these dunfields were excluded that were within the modeled inundation extent during a 1,274 m3/s (45,000 ft3/s) river flow scenario, representing the contemporary maximum controlled river flood release from Glen Canyon Dam. Dunefields are termed source-bordering aeolian dunefields and are comprised of wind deposited, river-sourced sand. The goal of the Grand Canyon Dune Atlas is to provide a GIS map of locations of dunefields for geomorphology research, and natural and cultural resource management. The data can be used to understand the locations and sizes of source-bordering aeolian dunefields that are comprised of wind deposited, Colorado River-sourced sand in the Grand Canyon, USA. Interpretations and applications of these data might be useful for natural or cultural resource management, or for geomorphology research on Earth and canyon environments on other planets. These data are intended to map all known active aeolian dunefield locations along the Colorado River in Grand Canyon that, as of 2013 or later, met the process step requirements for consideration as source bordering aeolian dunefields (SBD) or other aeolian-dominated sand areas (ADA), meaning a significant portion of the surface was bare sand. Historic aeolian dunefield locations or inactive portions of dunefields within this dataset that, by 2013, were highly vegetated or otherwise stabilized were not included. The dunefield polygons presented in this dataset represent the dunefield extent and can include vegetation within these extents. 2013 ground condition Complete None planned -113.3785383 -111.5925164 36.8651523 35.7750056 USGS Thesaurus field activity logs field inventory and monitoring geomorphology geospatial datasets hyperspectral imaging remote sensing river systems sand deposits sedimentation streamflow surface water (non-marine) unconsolidated deposits wind USGS Metadata Identifier USGS:670974ead34e969edc5a2c07 USGS information products data release ISO 19115 Topic Categories boundaries environment geoscientificInformation imageryBaseMapsEarthCover None aeolian aeolian-dominated sand area analog dune dunefield field data fluvial planetary analog source bordering aeolian dunefield terrestrial analog Geographic Names Information System (GNIS) Arizona Colorado River Diamond Creek Grand Canyon Lees Ferry Getty Thesaurus of Geographic Names Glen Canyon Dam United States Western United States None Northern Arizona No access constraints No use constraints. License, Creative Commons Zero v1.0 Universal. Joel B Sankey U.S. Geological Survey Research Geologist mailing and physical

Mail Stop 150, 2255 North Gemini Drive

Flagstaff AZ 86001 US 928-556-7289 jsankey@usgs.gov This work was supported by the National Science Foundation Non-Academic Research Internships for Graduate Students (NSF INTERN) program, the USGS Ecosystems Mission Area, and the Glen Canyon Dam Adaptive Management Program through the U.S. Bureau of Reclamation. Amy E. Draut 2012 Wiley Online Library Journal of Geophysical Research: Earth Surface https://doi.org/10.1029/2011JF002329 Laura E. Durning Joel B. Sankey Philip A. Davis Temuulen T. Sankey 2016 USGS Publications Warehouse (online) U.S. Geological Survey https://doi.org/10.3133/ds1027 Amy E. East Brian D. Collins Joel B. Sankey Skye C. Corbett Helen C. Fairley Joshua J. Caster 2016 USGS Publications Warehouse (online) U.S. Geological Survey http://dx.doi.org/10.3133/pp1825 Christopher S. Magirl Michael J. Breedlove Robert H. Webb Peter G. Griffiths 2008 USGS Publications Warehouse (online) U.S. Geological Survey https://doi.org/10.3133/sir20085075 Joel B. Sankey Amy East Helen C. Fairley Joshua Caster Jennifer Dierker Ellen Brennan Lonnie Pilkington Nathaniel Bransky Alan Kasprak 2023 Elsevier (ScienceDirect online) Journal of Environmental Management https://doi.org/10.1016/j.jenvman.2023.118036 The unique values for each attribute field were reviewed and checked for accuracy, adherence to controlled vocabularies, character encoding, completeness, consistency of terms and spelling. The data values are valid, and the units are aligned with the measurement being represented. Capitalization and punctuation are used consistently and, where applicable, follow standard conventions. Attribute values are within expected ranges for a particular field and do not contain any duplicate records or features. Data values were queried to confirm that numerical values were not outside a reasonable range for a particular field. Data were examined for proper spelling and consistency, abbreviations or codes, and standardization of all text fields. Data value unit abbreviation codes were compared with code names were for consistency. Polygons were checked (geometry), reviewed, and validated using ArcGIS mapping software tools. Data set is considered complete for the information presented, as described in the abstract. Data do not contain any proprietary or sensitive information. Users are advised to read the rest of the metadata record carefully for additional details. No formal positional accuracy tests were conducted No formal positional accuracy tests were conducted Laura E. Durning Joel B. Sankey Philip A. Davis Temullen T. Sankey 2016 GeoTIFF raster data Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/F7TX3CHS digital raster data 20130525 20130530 ground condition 2013 imagery These 2013 imagery data were used to visually inspect each dunefield during the data quality assessment and quality control (QAQC) process. Amy East 2016 tabular data unpublished data U.S. Geological Survey unpublished data digital tabular data 20160101 20161231 ground condition dunefield field data These 2016 field data were used to visually inspect each dunefield during the data quality assessment and quality control (QAQC) process. Thomas M. Gushue 2019 Vector digital dataset in ESRI geodatabase (points) Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/P9IRL3GV digital vector data 20190101 20191231 publication date GCMRC mile system These 2019 spatial point data were used to assign an associated river mile to each dunefield. Grand Canyon Monitoring and Research Center Michael Breedlove 2008 Vector Digital Data Set (ArcGIS geodatabase) Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/F7J67F0P digital vector data (polygon) 20020101 20021231 ground condition GIS polygon data (Christopher S. Magirl, modeled water-surface elevations and virtual shorelines, 1274 m3s) These modeled water-surface elevations and virtual shoreline spatial polygon data (1274 m3s) were used to clip the 2013 sand classification polygons based on the inundation boundary from the 45,000 ft3/s modeled river flow scenario to only include sand that would not be inundated by, and thus is located above, that modeled river stage elevation. Joel Sankey Barbara Ralston Paul Grams Jack Schmidt Laura Cagney 2015 Vector Digital Data (ArcGIS geodatabase) Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/F7J67F0P digital vector data (polygon) 19650101 20091231 observed GIS polygon data (Christopher S. Magirl, modeled water-surface elevations and virtual shorelines, 1274 m3s) These modeled water-surface elevations and virtual shoreline spatial polygon data (1274 m3s) were used to clip the 2013 sand classification polygons based on the inundation boundary from the 45,000 ft3/s modeled river flow scenario to only include sand that would not be inundated by, and thus is located above, that modeled river stage elevation. Joel B. Sankey Geoff R. Chain Daniel Solazzo Laura E. Durning Ashton Bedford Paul E. Grams Robert P. Ross 2018 ArcGIS geodatabase Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/P99TN424 digital vector data 20020101 20130530 ground condition Sand Classification 2013 polygons These sand classification polygon data from 2013 were used to develop the Grand Canyon dune atlas polygon shapefile. Joel B. Sankey Amy East Joshua Caster Helen Fairley Jennifer Dierker Ellen Brennan Lonnie Pilkington Nathaniel Bransky Alan Kasprak 20230515 tabular data Flagstaff, AZ U.S. Geological Survey https://doi.org/10.5066/P9X9ZDPK digital tabular data 19730101 20221231 ground condition aeolian classification metric data These aeolian classification metric data were used to develop the Grand Canyon dune atlas polygon shapefile. Development of the GC_DuneAtlas shapefile: The 2013 sand classification polygons (Sankey 2018) were clipped using the inundation boundary from the 45,000 ft3/s modeled river flow scenario (Grand Canyon Monitoring and Research Center and Breedlove 2008, Sankey 2015) to only include sand that would not be inundated by, and thus is located above, that modeled river stage elevation. The remaining sand polygons that were bigger than 100 m2 or not located within a tributary were selected and buffered. The polygon buffer distance was 25% of the perimeter of the minimum enclosing rectangle. Any overlapping sand polygon buffers and any buffers that intersected the modeled river stage elevation on the same local geomorphic landform (i.e. shared debris fan shoreline) were then merged together into a dunefield. Each dunefield was also assigned a river mile based on the GCMRC mile system (Gushue 2019), where river mile 0 is at USGS Colorado River at Lees Ferry, Arizona river gage 09380000 (Latitude 36°51'51.60", Longitude 111°35'16.34", NAD83). Next, each dunefield was evaluated for four criteria to determine if they could be classified as source-bordering aeolian dunefields (SBD), aeolian-dominated sand areas (ADA), or neither. Next, each dunefield was evaluated for four criteria to determine if they could be classified as source-bordering aeolian dunefields (SBD, 58 polygons), aeolian-dominated sand areas (ADA, 60 polygons), or neither. The four criteria are: (1) visible dune morphology; (2) visible aeolian indicators; (3) aeolian activity of sand; (4) aeolian classification for archaeological sites. Each dunefield was visually inspected, using the 2013 imagery (Durning 2016) and field data (East 2016, unpublished data), for: (1) visible dune morphology, such as lee and stoss slopes, avalanching slip faces, or blowouts and depositional lobes. They were also visually inspected during field visits for; (2) other aeolian indicators, such as sand shadows and ripples (East 2016, page 104) and for; (3) inactivity due to biocrust and vegetation cover (Draut 2012, including jgrf956-sup-0001-t01.txt). Lastly, their; (4) proximity to known archaeological sites and the archaeological site’s aeolian classification (Sankey 2023) were also considered. If the dunefield had visible dune morphology and any of the other three remaining criteria were true, then it was classified as an SBD. If the dunefield had no visible dune morphology and any of the other three remaining criteria were true, then it was classified as an ADA. Areas for which none of the criteria were true, were not classified as SBD or ADA. 2022 Data Quality Assessment and Quality Control (QAQC): No formal accuracy assessment was conducted. 2022 Finalize Data for Dissemination: Data sent to the Southwest Biological Science Center Data Steward for dissemination and preservation per USGS Data Management Policies SM 502.6, SM 502.7, SM 502.8 and SM 502.9 (1 October 2016). 2025 Vector G-polygon 118 State Plane Coordinate System 1983 0202 0.9999 -111.916666667 31.0 213360.0 0.0 coordinate pair 0.10 0.10 meters North American Datum of 1983 (2011) Geodetic Reference System 1980 6378137.0 298.257222101 GC_DuneAtlas This shapefile represents dunefields along the Colorado River in the Grand Canyon. The purpose of this shapefile is to delineate source-bordering aeolian dunefields that are comprised of wind deposited, Colorado River-sourced sand in the Grand Canyon, USA. Producer defined FID In ArcGIS, a system-managed value that uniquely identifies a record or feature. ESRI 0 117 integer number Shape In ArcGIS, the characteristic appearance or visible form of a geographic object as represented on a map. A GIS uses points, lines, and polygons to represent the shapes of geographic objects. ESRI Polygon On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique. ESRI Dunefield ID This attribute in the shapefile table represents a numeric identifier for each dunefield. Producer defined 1 118 integer number Dunefield Name This attribute in the shapefile table represents a plain text name for each dunefield. Producer defined A textual description of salient geographic, geomorphic, or river mile details for the polygon feature class, to assist in identifying its location. Tenth Mile This attribute in the shapefile table represents a numeric value for the river mile based on the Grand Canyon Monitoring & Research Center river mile system. River mile zero is at USGS Colorado River at Lees Ferry, Arizona river gage 09380000 (Latitude 36°51'51.60", Longitude 111°35'16.34", NAD83) Producer defined 0.7 224.8 river mile Class This attribute in the shapefile table represents a general description of sand sources. Producer defined ADA Aeolian dominated area Producer defined SBD Source-bordering dunefield Producer defined Area This attribute in the shapefile table represents the area of each dunefield in square meters. Producer defined 1148.25 72660.21 square meters Perimeter This attribute in the shapefile table represents the perimeter of each dunefield in meters. Producer defined 272.217 11943.172 meters GS ScienceBase U.S. Geological Survey mailing and physical

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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. These data are available in ESRI shapefile format. The user must have software capable of displaying the vector feature class dataset. 20250307 Joel B Sankey U.S. Geological Survey Research Geologist mailing and physical

Mail Stop 150, 2255 North Gemini Drive

Flagstaff AZ 86001 United States 928-556-7289 jsankey@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998