メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4187500 36.8208334, 137.4250000 36.8208334, 137.4250000 36.8250000, 137.4187500 36.8250000, 137.4187500 36.8208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral