John W. Counts Jared T. Gooley Joshua H. Long William H. Craddock Paul O'Sullivan 20241007 1 tabular digital data Reston, Virginia U.S. Geological Survey https://doi.org/10.5066/P9C91HEL U-Pb isotopic data from zircon grains from the sediment bedload of seven modern rivers: the Susquehanna, Potomac, Roanoke, James, Peedee, Tar, and Cape Fear, as well as from three samples taken from beaches in Albemarle and Pamlico Sounds (North Carolina), two Pleistocene core samples, and three samples on the ocean-facing foreshore of the Outer Banks barrier islands (North Carolina and Virginia). All analyses were conducted either by the University of Arizona LaserChron Center or Geosep Services (GSS). The data were collected in support of a publication investigating sediment sources in the Outer Banks region. The file contains data available in text (.txt) file format. The user must have software capable of opening and viewing a .txt file. 20211101 20240501 ground condition Complete None planned eastern United States -80.3320 -74.1138 40.3130 31.2786 ISO 19115 Topic Category oceans geoscientificInformation climatologyMeteorologyAtmosphere USGS Thesaurus geology None zircon geochronology sediment USGS Metadata Identifier USGS:65577194d34ee4b6e05c545b None USA Outer Banks North Carolina Virginia Pamlico Sound Albemarle Sound Susquehanna River Potomac River James River Roanoke River Cape Fear River Peedee River Tar River Pleistocene None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. John Counts U.S. Geological Survey Research Geologist mailing and physical

MS 956

Reston Virginia 20191 USA (703) 648-6491 jcounts@usgs.gov Windows 10 Enterprise, Microsoft Excel Sample locations were measured by handheld GPS and are accurate only to a meter-scale. For zircon analyses, standards were run throughout the process to ensure accuracy of obtained values. No formal logical accuracy tests were conducted. Dataset is considered complete for the information presented, as described in the abstract. 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. Sediment samples were collected by the authors in the field from 2018 to 2021. Approximately 20 liters of sediment were collected from natural sand bars at each site using a shovel and a bucket. Unknown All sediment samples were manually homogenized and split into subsamples at the U.S. Geological Survey in Reston, Virginia. All sample processing and geochemical analysis took place at the Arizona Laserchron Center at the University of Arizona (ALC) and at GeoSep Services in Moscow, Idaho (GSS). At ALC, initial separation of zircon grains was conducted via a multi-stage process, where bulk sediments were first subjected to magnetic (hand magnet and Franz magnetic separator), heavy liquid (Methylene Iodide), physical (milling device to remove softer heavy minerals), and chemical (acid washing to remove pyrite) processes. A complete document outlining separation methodology at ALC is available from Simpson et al. (2012). At GSS, zircon separation processes were similar. Sediments were sieved through 300 μm mesh, dried, and separated via centrifuge in lithium metatungstate, Franz magnetic separation, and heavy liquid separation in methylene iodide. Simpson, G., Pecha, M. and Gehrels, G., 2012. Mineral separation instruction manual. Arizona LaserChron Center, 1. https://drive.google.com/file/d/0B9ezu34P5h8eYzRmZGYwMGItMGI1MC00MGQ3LWE4YzEtNWZiZmFiNDQ5OGRh/view?usp=sharing&resourcekey=0-5BMGpY7CQ1UwgnbRSYFa9A Unknown After zircons were separated at both laboratories, a random selection of grains were mounted in a resin block and imaged under cathodoluminescence. Ablation sites were chosen for either 100 (fluvial source samples) or 300 (Outer Banks and Sound samples) individual grains in each sample to avoid visible areas of common lead contamination, and to avoid crossing boundaries of internal zones whenever possible. At ALC, U-Pb geochronology was conducted via laser ablation inductively coupled mass spectroscopy (LA-ICPMS) using a Photon Machines Analyte G2 excimer laser with a beam width of 30 µm and a Nu Instruments HR-MC-ICPMS. Standards were measured every five grains. At GSS, LA-ICPMS was conducted with a New Wave YP213 213 nm solid state laser ablation system using either a 20 or 30 μm diameter laser spot size. Unknown In order to make ALC and GSS data comparable, ages were calculated for GSS samples using data collected throughout the entire laser ablation process (“Isotopic Sums” columns in GSS reporting template) rather than using only those scans that resulted in concordant ages. Both ALC and GSS data were then filtered in the same way: grains were excluded if they had either 1) Discordance (defined as (1-(206Pb/238U Age/207Pb/206Pb Age))*100) values outside of the 80-110% range), or 2) uncertainty values in the 206Pb/238U Age greater than 10%. Unknown OBX DZ U-Pb Data.txt Analytical data (U/Pb geochronology) for sediment samples from the Appalachian and Outer Banks regions of eastern North America. Data presented in tab-delimited text file. Producer Defined Sample Site Name of geographic feature from which sample was collected. Producer Defined James River Sample collected from the James River Producer defined Roanoke River Sample collected from the Roanoke River Producer defined Tar River Sample collected from the Tar River Producer defined Cape Fear River Sample collected from the Cape Fear River Producer defined Peedee River Sample collected from the Peedee River Producer defined Potomac River Sample collected from the Potomac River Producer defined Susquehanna River Sample collected from the Susquehanna River Producer defined Chowan River (AS1) Sample collected from the estuary of the Chowan River Producer defined Neuse River (NR) Sample collected from the estuary of the Neuse River Producer defined Pamlico River (PR) Sample collected from the estuary of the Pamlico River Producer defined False Cape State Park (BI3A) Sample collected from the Atlantic Ocean foreshore in False Cape State Park, Virginia Producer defined Cape Hatteras (H2A) Sample collected from the Atlantic Ocean foreshore near Cape Hatteras, North Carolina Producer defined Cape Lookout (SCB1A) Sample collected from the Atlantic Ocean foreshore near Cape Lookout, North Carolina Producer defined Roanoke River Braidplain (SAS20-GP4) Sample collected from Pleistocene sediments deposited as part of the lower Roanoke River braidplain, from core GH-10. Producer defined Suffolk Shoreline Complex (GH-10) Sample collected from Pleistocene sediments deposited as part of the Suffolk Shoreline Complex, from core GH-10. Producer defined Laboratory Laboratory in which the analysis was conducted Producer Defined GSS GeoSep Services, Moscow, Idaho Producer defined Arizona LaserChron University of Arizona LaserChron Center, Phoenix, Arizona Producer defined Latitude Latitude of sample collection site Producer Defined -76.7487 76.7569 Longitude Longitude of sample collection site. Producer Defined -79.8681 36.5714 Analysis Name Name of individual analysis spot (i.e., laser ablation site) given by the lab conducting the analysis. Producer Defined Original names of individual analyses given by the laboratory in which the sample was run. 207Pb/235U Ratio 207Pb/235U Ratio Producer Defined N/A No Data Producer defined -46.65 9367299.105 207Pb/235U 2S (%) Uncertainty (in percent of) 207Pb/235U Ratio Producer Defined N/A No Data Producer defined 0.9368 72977.9154 206Pb/238U Ratio 206Pb/238U Ratio Producer Defined N/A No Data Producer defined 0.0198 3135.8652 206Pb/238U 2S (%) Uncertainty (in percent of) 206Pb/238U Ratio Producer Defined N/A No Data Producer defined 0.6337 3882.7021 Error Correlation Error Correlation Producer Defined N/A No Data Producer defined 0.0041 0.9998 238U/206Pb Ratio 238U/206Pb Ratio Producer Defined N/A No Data Producer defined 0.0003 50.5409 2S (%) Uncertainty (in percent) of 238U/206Pb Ratio. Producer Defined N/A No Data Producer defined 0.6337 3882.7021 207Pb/206Pb Ratio 207Pb/206Pb Ratio Producer Defined N/A No Data Producer defined -1.6842 21.6746 207Pb/206Pb 2S (%) Uncertainty (in percent) of 207Pb/206Pb Ratio. Producer Defined N/A No Data Producer defined 0.6743 72971.637 207Pb/235U Age (Ma) Age as determined by 207Pb/235U ratio. Producer Defined N/A No Data Producer defined 32.388 16299.6756 207Pb/235U Age Avg 2S (My) Uncertainty (in Ma) for 207Pb/235U age. Producer Defined N/A No Data Producer defined 4.6324 3822.8009 206Pb/238U Age (Ma) Age as determined by 206Pb/238U ratio. Producer Defined N/A No Data Producer defined 126.303 51899.9468 206Pb/238U Age Avg 2S (My) Uncertainty (in My) for age determined by 206Pb/238U ratio. Producer Defined N/A No Data Producer defined 2.3657 25105.0874 6/8 Uncertainty (%) Uncertainty (in percent) of 206Pb/238U age Producer Defined N/A No Data Producer defined 0.5796 4603.2441 207Pb/206Pb Age (Ma) Age as determined from 207Pb/206Pb ratio. Producer Defined N/A No Data Producer defined 0.046 3759.1617 207Pb/206Pb Age Avg 2S (My) Uncertainty for ages determined by 207Pb/206Pb ratio (in My) Producer Defined N/A No Data Producer defined 1 1788.5936 Calculated discordance Discordance value, defined by 1-(206Pb/238U Age/207Pb/206Pb Age))*100) Producer Defined Not calculated Discordance was not calculated by the author Producer defined -13042.6977 100 Concordia Age Concordia age, as calculated by: Vermeesch, P., 2021.On the treatment of discordant detrital zircon U–Pb data, Geochronology, 3, 247–257. Producer Defined N/A No Data or not calculated Producer defined 0.1402 28449.976 Concordia error (My) Error in Concordia age, in My Producer Defined N/A No Data or not calculated Producer defined 0.0894 7040.6907 Notes Analysis notes by the author Producer Defined << empty cell >> No Data Producer defined Atypical values encountered during analysis; data may be unsuitable for geochronology Some analytical values are anomalous and may prevent grain from being included in final data set. Producer defined GS ScienceBase U.S. Geological Survey mailing address

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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 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. Digital Data https://doi.org/10.5066/P9C91HEL None 20241007 John W Counts U.S. Geological Survey, Northeast Region Research Geologist mailing address

Mail Stop 954, 12201 Sunrise Valley Dr

Reston VA 20192 US 703-648-6491 703-648-6383 jcounts@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999