U.S. DEPARTMENT OF THE INTERIOR / U.S. GEOLOGICAL SURVEY U.S. GEOLOGICAL SURVEY DIGITAL DATA SERIES DDS-13 International Phase of Ocean Drilling Seismic Line 1 Demultiplexed Data Cape Hatteras to Mid-Atlantic Ridge README.2ND DOCUMENTATION FILES EXPLANATION .TXT: ASCII text files. .DOC: Microsoft Word V6.0 files.