If a DB table is 3TB in size and read speed is 10mbyte/sec. Does it mean that 83hours are necessary to create new index?

One of our custom log tables is 3TB in size. We need to create a new index. Read speed on the disk itself is 10mbyte/sec.

Does this mean that the index creation process will be 3.000.000/10 = 86 hours? The index is written to another filegroup on a fast disk so write time is not a factor.