メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((136.6937500 35.4208334, 136.7000000 35.4208334, 136.7000000 35.4250000, 136.6937500 35.4250000, 136.6937500 35.4208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral