<ARTICLE>                     5
<LEGEND>
This  schedule  contains  summary  financial   information  extracted  from  the
Consolidated  Balance  Sheet at December  31, 1997 and the related  Statement of
Consolidated Income for the year ended December 31, 1997 and is qualified in its
entirety by reference to such financial statements.

</LEGEND>
<MULTIPLIER>                                   1,000
       
                             
<PERIOD-TYPE>                   12-MOS
<FISCAL-YEAR-END>                                DEC-31-1997      
<PERIOD-END>                                     DEC-31-1997
<CASH>                                                94,725
<SECURITIES>                                         141,221
<RECEIVABLES>                                         40,366
<ALLOWANCES>                                               0
<INVENTORY>                                           69,258
<CURRENT-ASSETS>                                     357,970
<PP&E>                                             1,959,222
<DEPRECIATION>                                     1,147,176
<TOTAL-ASSETS>                                     1,304,729
<CURRENT-LIABILITIES>                                108,906
<BONDS>                                              263,855
<PREFERRED-MANDATORY>                                      0
<PREFERRED>                                                0
<COMMON>                                             146,735
<OTHER-SE>                                           385,015
<TOTAL-LIABILITY-AND-EQUITY>                       1,304,729
<SALES>                                              659,914
<TOTAL-REVENUES>                                     723,834
<CGS>                                                585,858 <F1>
<TOTAL-COSTS>                                        626,421 <F2>
<OTHER-EXPENSES>                                     254,003 <F3>
<LOSS-PROVISION>                                           0
<INTEREST-EXPENSE>                                    11,259
<INCOME-PRETAX>                                     (167,849)
<INCOME-TAX>                                          (9,211)
<INCOME-CONTINUING>                                 (168,879)
<DISCONTINUED>                                             0
<EXTRAORDINARY>                                            0
<CHANGES>                                                  0
<NET-INCOME>                                        (168,879)
<EPS-PRIMARY>                                          (1.15)
<EPS-DILUTED>                                          (1.15)
<FN>
<F1> Includes  Production  costs and  Depreciation,  depletion and amortization
     from the Statement of Consolidated Operations.
<F2> Includes Production costs,  Depreciation,  depletion and amortization,  and
     Administrative   and  general   expense  from  Statement  of   Consolidated
     Operations.
<F3> Includes  Exploration  expense, Write-downs  and other unusual charges, and
     Other expense from Statement of Consolidated Operations.

</FN>