NOAA bathymetric data offshore raster block is what?

[forestknutsen1]

I am wondering what the blocks offshore are called in a NOAA bathymetric chart? And what do they represent.

NGDC/MGG-Download NOS Scanned Bathymetric and Fishing Maps Alaska & Bering Sea North of 58 degrees

I did some looking around on the web but could not find anything definite.

Thanks for any input!

Forest

[forestknutsen1 · Accepted solution]

Outer Continental Shelf Lease Blocks