メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.3562500 31.5208334, 131.3625000 31.5208334, 131.3625000 31.5250000, 131.3562500 31.5250000, 131.3562500 31.5208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral