Hi Jim, Thanks very much for the response - I got a good chuckle out of your comment that the units could be leagues or cubits... I had assumed as you state in your second post that perhaps the length variable units were IP based as well.  I see that the minimum value for depth in the dataset is -3.3 which I assume to be above sea level, so since there is no published record to my knowledge to dispute me, I assigned the length variables with the km unit and called that roughly 10,827 feet above sea level. Thanks again, Chris ... View more