メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4000000 34.8000000, 137.4062500 34.8000000, 137.4062500 34.8041667, 137.4000000 34.8041667, 137.4000000 34.8000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral