メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.3625000 42.8208334, 143.3687500 42.8208334, 143.3687500 42.8250000, 143.3625000 42.8250000, 143.3625000 42.8208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral