Answer by cljk for How do I check whether I am using LVM?

You should see it in Gparted.You can also just check your fstab file:

cat /etc/fstab

Watch the line with your root filesystem. Three possibilities here:

1. If the line starts with UUID=xyz, this means it's a physical partition.
2. If the line starst with /dev/sdaX, it also means it's a physical partition.
3. The indicator for LVM would be something with /dev/mapper/xyz.