Field Definitions are Available Here
Collection
string (80)
This attribute specifies a word or phrase which serves to summarize the spatial regions covered by the collection. It may be repeated if several regions are covered. This often occurs when a collection is described as covering some large region, and several smaller sub regions within that region.
POINT LOCATIONS
/SpatialKeywords/Keyword
/gmi:MI_Metadata/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:descriptiveKeywords/gmd:MD_Keywords/gmd:keyword/gco:CharacterString
Spatial Information (ECHO)