メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.7187500 34.8541667, 137.7250000 34.8541667, 137.7250000 34.8583333, 137.7187500 34.8583333, 137.7187500 34.8541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral