Hi
You can add a new depreciation area to the assets using AFBN
Activate the new dep area in CoD first.. you need to specify how the new dep area will get it values (Wheter inherit from 01 or you will add it later manually)
You can read SAP Help http://help.sap.com/saphelp_46c/helpdata/en/c7/dfbd911f1e11d384a700104b55af8e/content.htm
You can also search in google / SCN as "Adding new depreciation area"
Br. Ajay M