<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM QUARTERLY
REPORT ON 10-Q AND IS QUALIFIED IN ITS ENTIRETY BY REFENENCE TO SUCH FINANCIAL
STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               JUN-30-1997
<CASH>                                          28,110
<SECURITIES>                                     6,075
<RECEIVABLES>                                   10,581
<ALLOWANCES>                                         0
<INVENTORY>                                      1,756
<CURRENT-ASSETS>                                40,975
<PP&E>                                         324,947
<DEPRECIATION>                                 120,705
<TOTAL-ASSETS>                                 255,443
<CURRENT-LIABILITIES>                           16,065
<BONDS>                                        124,261
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        27,379
<OTHER-SE>                                      75,094
<TOTAL-LIABILITY-AND-EQUITY>                   255,443
<SALES>                                         39,269
<TOTAL-REVENUES>                                43,399
<CGS>                                           14,334
<TOTAL-COSTS>                                   37,769
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               3,355
<INCOME-PRETAX>                                  5,630 
<INCOME-TAX>                                     1,433 
<INCOME-CONTINUING>                              4,197 
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     4,197 
<EPS-PRIMARY>                                      .47 
<EPS-DILUTED>                                      .47