col_id: The unique identification number for the column.
col_group_id: The unique identification number of the group to
which the column belongs.
col_name: The name of the column.
lat: Latitude of the centroid of the column.
lng: Longitude of the centroid of the column.
col_area: Area of the Macrostrat column,
in km2.
max_thick: Maximum unit thickness in meters.
ref_id: The unique identification number for the reference
associated with the column.
status: Indicates the current status of the column (values are
'active', 'in process', and 'obsolete').
t_units: Total number of Macrostrat units contained within the
column.
project_id: The unique identification number for the column's
project. Corresponds to general geographic region.
notes: Column specific notes.