Explanation/Reference:
Create index mdsys.spatial_index local
Creating a Local Partitioned Spatial Index
If you want to create a local partitioned spatial index, Oracle recommends that you use the procedure in this section instead of using the PARALLEL keyword, to avoid having to start over if the creation of any partition's index fails for any reason (for example, because the tablespace is full). Follow these steps:
Create a local spatial index and specify the UNUSABLE keyword. For example:
CREATE INDEX sp_idx ON my_table (location)
INDEXTYPE IS mdsys.spatial_index
PARAMETERS ('tablespace=tb_name work_tablespace=work_tb_name')
LOCAL UNUSABLE;
This statement executes quickly and creates metadata associated with the index.
References: https://docs.oracle.com/database/121/SPATL/creating-local-partitioned-spatial-index.htm