<ARTICLE>                     5
<LEGEND>
This  schedule  contains  summary  financial   information  extracted  from  the
Condensed  Consolidated  Balance  Sheet at  September  30,  1998 and the related
Condensed  Statement  of  Consolidated  Operations  for  the nine  months  ended
September  30,  1998 and is  qualified  in its  entirety  by  reference  to such
financial statements.
</LEGEND>
<MULTIPLIER>                                   1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                         DEC-31-1998
<PERIOD-END>                              SEP-30-1998
<CASH>                                        151,311
<SECURITIES>                                  157,952
<RECEIVABLES>                                  36,900
<ALLOWANCES>                                        0
<INVENTORY>                                    78,724
<CURRENT-ASSETS>                              441,441
<PP&E>                                      2,193,753
<DEPRECIATION>                              1,430,163
<TOTAL-ASSETS>                              1,315,928
<CURRENT-LIABILITIES>                         157,188
<BONDS>                                       354,451
<PREFERRED-MANDATORY>                               0
<PREFERRED>                                         0
<COMMON>                                      211,204
<OTHER-SE>                                    195,391
<TOTAL-LIABILITY-AND-EQUITY>                1,315,928
<SALES>                                       609,308
<TOTAL-REVENUES>                              594,931
<CGS>                                         513,324<F1> 
<TOTAL-COSTS>                                 549,489<F2>
<OTHER-EXPENSES>                              261,447<F3>
<LOSS-PROVISION>                                    0
<INTEREST-EXPENSE>                             15,813
<INCOME-PRETAX>                              (231,818)  
<INCOME-TAX>                                  (12,998)
<INCOME-CONTINUING>                          (219,743)  
<DISCONTINUED>                                      0
<EXTRAORDINARY>                                     0
<CHANGES>                                           0
<NET-INCOME>                                 (219,743) 
<EPS-PRIMARY>                                   (1.04)   
<EPS-DILUTED>                                   (1.04) 

<FN>
<F1> Includes Production costs and Depreciation, depletion and amortization from
Condensed Statement of Consolidated Operations.
<F2> Includes Production costs and Depreciation,  depletion and amortization and
Administrative  and general  expense from  Condensed  Statement of  Consolidated
Operations.
<F3>  Includes  Exploration  expense,  Write-downs  and other  unusual  charges,
Business  combination  and  integration  cost and Other  expense from  Condensed
Statement of Consolidated Operations.
</FN>