@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix dct: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix gsp: <http://www.opengis.net/ont/geosparql#> .
@prefix locn: <http://www.w3.org/ns/locn#> .
@prefix vcard: <http://www.w3.org/2006/vcard/ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://data.amerigeoss.org/dataset/7e6f2b8f-e7df-405c-bd2c-838b41d44669> a dcat:Dataset ;
    dct:description "Water samples from 50 domestic wells located &lt;1 kilometer (km) (proximal) and &gt;1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas compared to valleys. Methane (CH4) -isotope and pre-drill CH4 data indicate one proximal sample (5 percent of proximal samples) contains thermogenic CH4 (2.6 milligrams per liter (mg/L)) associated with shale-gas production. Chloride (Cl), bromide (Br), lithium (Li), and neon-20 (20Ne)/argon-36 (36Ar) data suggest that CH4 leaked from a nearby gas well in a gas phase. Another proximal sample contains volatile hydrocarbons (0.03-0.4 micrograms per liter (µg/L)), including benzene, found in some hydraulic fracturing fluid. Modeled groundwater-age distributions, calibrated to tritium (3H), sulfur hexafluoride (SF6), and carbon-14 (14C) concentrations, indicate that water recharged prior to shale-gas development, suggesting surface releases associated with shale-gas production were not the source of those hydrocarbons, although leakage from a nearby gas well directly into the old groundwater cannot be ruled out. Estimated age distributions in the samples span ~20 to &gt;10,000 years and have implications for relating occurrences of hydrocarbons in groundwater to surface releases associated with recent shale-gas production, and to the time required to flush contaminants from the system.  This data release contains isotopic tracer, noble gas, and groundwater-age tracer concentration data collected by the U.S. Geological Survey and data for pH, specific conductance, major ions, and methane collected by Chesapeake Energy Corporation." ;
    dct:identifier "USGS:5c58ad28e4b0708288ff2ab6" ;
    dct:issued "2025-11-22T22:57:44.149125"^^xsd:dateTime ;
    dct:modified "20200826"^^xsd:gYear ;
    dct:publisher <https://data.amerigeoss.org/organization/727dbdd5-3f98-4ac0-9d28-5e344558139b> ;
    dct:spatial [ a dct:Location ;
            locn:geometry "POLYGON ((-77.0990 41.1428, -77.0990 42.5552, -75.2590 42.5552, -75.2590 41.1428, -77.0990 41.1428))"^^gsp:wktLiteral ] ;
    dct:title "Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA" ;
    dcat:contactPoint [ a vcard:Organization ;
            vcard:fn "Peter B. McMahon" ;
            vcard:hasEmail <mailto:pmcmahon@usgs.gov> ] ;
    dcat:distribution <https://data.amerigeoss.org/dataset/7e6f2b8f-e7df-405c-bd2c-838b41d44669/resource/1fa9742c-02f7-468e-b9c5-8b280c9dab36>,
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    dcat:keyword "amerigeo",
        "amerigeoss",
        "bradford-county-pa",
        "broome-county-ny",
        "ckan",
        "cycle-3",
        "domestic-well",
        "geo",
        "geoss",
        "groundwater",
        "groundwater-age-distribution",
        "hydrocarbons",
        "marcellus-shale",
        "national",
        "nawqa",
        "new-york",
        "north-america",
        "pennsylvania",
        "shale-gas-well",
        "sullivan-county-pa",
        "susquehanna-county-pa",
        "tioga-county-ny",
        "united-states",
        "usgs-5c58ad28e4b0708288ff2ab6",
        "water-quality",
        "wyoming-county-pa" ;
    dcat:theme <%7Bgeospatial%7D> .

<https://data.amerigeoss.org/dataset/7e6f2b8f-e7df-405c-bd2c-838b41d44669/resource/1fa9742c-02f7-468e-b9c5-8b280c9dab36> a dcat:Distribution ;
    dct:description "Landing page for access to the data" ;
    dct:format "XML" ;
    dct:issued "2022-07-28T21:06:28.046940"^^xsd:dateTime ;
    dct:modified "2025-11-22T22:57:44.133817"^^xsd:dateTime ;
    dct:title "Digital Data" ;
    dcat:accessURL <https://doi.org/10.5066/P93M7JCD> ;
    dcat:mediaType "application/http" .

<https://data.amerigeoss.org/dataset/7e6f2b8f-e7df-405c-bd2c-838b41d44669/resource/20394690-19dc-41cb-9b71-dccd26a767a2> a dcat:Distribution ;
    dct:description "The metadata original format" ;
    dct:format "XML" ;
    dct:issued "2022-07-28T21:06:28.046930"^^xsd:dateTime ;
    dct:modified "2025-11-22T22:57:44.133415"^^xsd:dateTime ;
    dct:title "Original Metadata" ;
    dcat:accessURL <https://data.usgs.gov/datacatalog/metadata/USGS.5c58ad28e4b0708288ff2ab6.xml> ;
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<https://data.amerigeoss.org/organization/727dbdd5-3f98-4ac0-9d28-5e344558139b> a foaf:Agent ;
    foaf:name "United States" .