{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Tyler B. Coplen", "hasEmail": "mailto:tbcoplen@usgs.gov"}, "description": "Twelve chemical elements have intervals for their standard atomic weights, namely hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine and thallium. Isotopic abundances, isotope-delta values, and atomic weights for each of the lower and upper bounds of materials and compounds of these 12 elements are tabulated. Version 1.1 is the most current version.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/F7GF0RN2", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}, {"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.580e719ae4b0f497e794b7d8.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_580e719ae4b0f497e794b7d8", "keyword": ["USGS:580e719ae4b0f497e794b7d8", "isotopic abundances"], "modified": "2026-07-22T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-180.0, -90.0, 180.0, 90.0", "theme": ["geospatial"], "title": "Tables and charts for isotope-abundance variations and atomic weights of selected elements: 2016 (ver. 1.1, May 2018)"}