<ARTICLE> 5
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE COMPANY'S
CONSOLIDATED FINANCIAL STATEMENTS AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE
TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1996
<PERIOD-END>                               SEP-30-1996
<CASH>                                          18,706
<SECURITIES>                                         0
<RECEIVABLES>                                   28,098
<ALLOWANCES>                                         0
<INVENTORY>                                      6,317
<CURRENT-ASSETS>                                59,987
<PP&E>                                         580,824
<DEPRECIATION>                               (179,274)
<TOTAL-ASSETS>                                 547,707
<CURRENT-LIABILITIES>                          107,054
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           313
<OTHER-SE>                                     263,957
<TOTAL-LIABILITY-AND-EQUITY>                   547,707
<SALES>                                        399,805
<TOTAL-REVENUES>                               399,805
<CGS>                                                0
<TOTAL-COSTS>                                  331,722
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                              13,396
<INCOME-PRETAX>                                 56,240
<INCOME-TAX>                                    22,296
<INCOME-CONTINUING>                             33,944
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    33,944
<EPS-PRIMARY>                                     1.08
<EPS-DILUTED>                                     1.08