Dept. of the Interior
U.S. Geological Survey
Energy Resources Team

Selected Data from Eleven Wildcat Wells in 
the National Petroleum Reserve in Alaska

USGS Open File Report 99-015


Depths to Selected Stratigraphic Horizons

WELL NAME ROCK UNIT                                                                 DEPTH, FEET
INIGOK 1  Surficial Deposits and/or Gubik Formation                                 43.00                 
INIGOK 1  Sandstone of the Colville Group and Sagavanirktok Formation               100.00                
INIGOK 1  Shale of the Colville Group                                               1380.00               
INIGOK 1  Nanushuk Group                                                            2250.00               
INIGOK 1  Torok Formation                                                           3935.00               
INIGOK 1  Pebble Shale Unit                                                         9040.00               
INIGOK 1  Kingak Shale                                                              9260.00               
INIGOK 1  Sag River Sandstone                                                       12160.00              
INIGOK 1  Shublik Formation                                                         12190.00              
INIGOK 1  Fire Creek Siltstone Member of the Ivishak Formation, Sadlerochit Group   12430.00              
INIGOK 1  Ledge Sandstone Member of the Ivishak Formation. Sadlerochit Group        12840.00              
INIGOK 1  Kavik Member of the Ivishak Formation, Sadlerochit Group                  13285.00              
INIGOK 1  Echooka Formation, Sadlerochit Group                                      13660.00              
INIGOK 1  Lisburne Group                                                            13985.00              
INIGOK 1  Endicott Group                                                            17870.00              

Data Source
Table 15.3. - Total depth and depths to selected stratigraphic horizons
for Government-drilled wells on the North Slope of Alaska., 
in:

Gryc, George, Ed., 1988, Geology and exploration of the National Petroleum
     Reserve in Alaska, 1974 to 1982, U.S. Geological Survey Professional 
     Paper 1399, Pgs. 322 - 324.