Correcting an sd-card?

[Linux for blind general discussion]

Yes. You will need to unmount your sd card before you repair it.
sudo umount /dev/sdg1
should do this, even if you have an automounter such as gvfs that mounts it 
automatically when you put it in your computer. This is the safest way, as 
sometimes umnount is not an option on the desktop menu, and eject will make the 
sd card inaccessible until you unplug and plug in your reader.
~Kyle