<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
COMPANY'S FINANCIAL STATEMENTS AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1996
<PERIOD-END>                               JUN-30-1996
<CASH>                                           5,051
<SECURITIES>                                     5,202
<RECEIVABLES>                                  144,812
<ALLOWANCES>                                         0
<INVENTORY>                                     31,085
<CURRENT-ASSETS>                               201,355
<PP&E>                                       1,320,319
<DEPRECIATION>                                 243,426
<TOTAL-ASSETS>                               1,367,329
<CURRENT-LIABILITIES>                           74,807
<BONDS>                                         70,000
<COMMON>                                           683  
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<OTHER-SE>                                   1,098,237
<TOTAL-LIABILITY-AND-EQUITY>                 1,367,329
<SALES>                                              0
<TOTAL-REVENUES>                               253,851
<CGS>                                                0
<TOTAL-COSTS>                                  147,754<F1>
<OTHER-EXPENSES>                                33,787<F2>
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                 104
<INCOME-PRETAX>                                 72,914
<INCOME-TAX>                                    21,160
<INCOME-CONTINUING>                             51,754
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    51,754
<EPS-PRIMARY>                                     0.92
<EPS-DILUTED>                                     0.92
<FN>
<F1>INCLUDES CONTRACT DRILLING EXPENSES ONLY.
<F2>INCLUDES OTHER OPERATING EXPENSES.
</FN>