メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.9187500 36.4250000, 137.9250000 36.4250000, 137.9250000 36.4291667, 137.9187500 36.4291667, 137.9187500 36.4250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral