Sorry, this line of reasoning / method of extracting information makes no sense at all. The Linux/Unix string utility displays printable characters when they occur consecutively in clumps of 4 or more. Everything else in the file is ignored! When a Fortran unformatted file is written, most of the bytes in the file correspond to “unprintable” characters, so by ignoring them you are discarding almost all the numerical information (integers, reals, etc.) and carrying on as if what is left is all that is important.
For instance, for the data file kLG_1.data, your application of strings and sed leaves discards 90 percent of the content of the file.
The question is, do you have the Fortran program sources that produced every one of the unformatted data files that are of interest to you? Or, at least complete and precise documentation of the structure and content of the files? If not, you are simply inviting us to go with you for a walk in a minefield while wearing blindfolds.