メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.7250000 35.7500000, 137.7312500 35.7500000, 137.7312500 35.7541667, 137.7250000 35.7541667, 137.7250000 35.7500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral