<ARTICLE> 5 <LEGEND> This schedule contains summary financial information extracted from the Condensed Consolidated Balance Sheet at September 30, 1997 and the related Condensed Statement of Consolidated Operations for the nine months ended September 30, 1997 and is qualified in its entirety by reference to such financial statements. </LEGEND> <MULTIPLIER> 1,000 <PERIOD-TYPE> 9-mos <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-END> SEP-30-1997 <CASH> 61,080 <SECURITIES> 168,882 <RECEIVABLES> 32,903 <ALLOWANCES> 0 <INVENTORY> 89,366 <CURRENT-ASSETS> 371,296 <PP&E> 2,002,307 <DEPRECIATION> 1,146,077 <TOTAL-ASSETS> 1,334,470 <CURRENT-LIABILITIES> 115,504 <BONDS> 222,183 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 146,744 <OTHER-SE> 447,500 <TOTAL-LIABILITY-AND-EQUITY> 1,334,470 <SALES> 497,786 <TOTAL-REVENUES> 577,070 <CGS> 439,814 <F1> <TOTAL-COSTS> 470,118 <F2> <OTHER-EXPENSES> 225,184 <F3> <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 7,659 <INCOME-PRETAX> (125,891) <INCOME-TAX> (3,960) <INCOME-CONTINUING> (130,044) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (130,044) <EPS-PRIMARY> (0.89) <EPS-DILUTED> 0 <FN> (1) Includes Produciton costs and Depreciation, depletion and amortization from Condensed Statement of Consolidated Operations. (2) Includes Production costs and Depreciation, depletion and amortization and Administrative and general expense from Condensed Statement of Consolidated Operations. (3) Includes Exploration expense, Write-downs and other unusual charges and Other expense from Condensed Statement of Consolidated Operations. </FN>