メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.6875000 34.7000000, 137.6937500 34.7000000, 137.6937500 34.7041667, 137.6875000 34.7041667, 137.6875000 34.7000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral