They do not appear to be marriages at all. US, Missouri—County Marriages, 1806–1969 [Part Q][MSQG-8DG]
You are correct, these are not marriages. You should mark these type of records No, No Extractable Data in Step 1.
They are " Archive Records Deeds, Land Grants, Accounts, Wills. French Spanish English Dated 1800."
The title of the film is:
St. Louis. Land Records 1848, Vital Records 1848, Notarial Records 1848 There are around 170 images that won't be indexed.
Thank you @Evan D. Fullmer and @Melissa S Himes!
This has been reported.