New answers tagged error
What you're seeing is consistent with data corruption in that the preview lo-res jpeg is fine, and that the compressed raw has a number of incorrect or missing bytes causing corruption. The question Why do images get "corrupted"? describes the effect at the file level. Use of a different file format (raw rather than jpeg) will give you different output but ...
For me this looks like storage card is broken. Replace it and test again P.S. And IMHO you can't fix the photos. You can try software like recuva to recover the files, but it's not sure what result you will get
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