A list with
coordsnames of the coordinates in the geodata object.
  dataname(s) of the data elements in the geodata object.
  units.mreturns the string units.m.
  covariatesreturn the covariate(s) name(s) if present
     in the geodata object
  realisationsreturns the string units.m  if present
    in the geodata object.
  otherother elements in the geodata  object.