<simpleType name="OrientationObsPropertyEnumType">
  <union>
    <simpleType>
      <restriction base="string">
        <enumeration value="bedding"/>
        <enumeration value="cross-bedding"/>
        <enumeration value="faults"/>
        <enumeration value="joints"/>
        <enumeration value="fractures"/>
      </restriction>
    </simpleType>
    <simpleType>
      <restriction base="string">
        <pattern value="Other: .{2,}"/>
      </restriction>
    </simpleType>
  </union>
</simpleType>