Default Direct read of NAND eraseblocks ?


I am just looking for information about how to read/write (if possible) an individual or a set of NAND eraseblocks on an android device regardless the partition in which eraseblocks are located.
Usually we are using commands like linux "dd" and specifying the partition whose eraseblock we want to read. My question is whether is possible or not to read NAND eraseblocks directly, regardless partitions, as the same way we can read an individual sector on a PC hard disk, simply specifying the offset and read the corresponding eraseblock.

Thanks in advance,
and please, sorry for my english :-/