メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.3687500 36.7208334, 137.3750000 36.7208334, 137.3750000 36.7250000, 137.3687500 36.7250000, 137.3687500 36.7208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral