EXHIBIT 99.1


                                                                 FOR INFORMATION
                                                                 ---------------
                                                             Mark A. Hellerstein
                                                               Jennifer Dethloff
                                                               Adele A. Linneman

FOR IMMEDIATE RELEASE
- ---------------------

               ST. MARY COMPLETES ACQUISITION OF KING RANCH ENERGY

     DENVER - December 17, 1999 - St. Mary Land & Exploration  Company  (Nasdaq:
MARY)  announced that it completed the  acquisition  of King Ranch Energy,  Inc.
("KRE"),  in a merger in which St. Mary issued  2,666,252  common  shares to the
stockholders of King Ranch, Inc., the former parent company of KRE.  Immediately
prior to the merger, KRE was spun-off to the King Ranch Stockholders in order to
facilitate the merger.  The shares issued by St. Mary are  restricted  from sale
through  March 31,  2001.  As a result of the merger,  KRE became a wholly owned
subsidiary of St. Mary and was renamed St. Mary Energy Company.

     KRE's  properties  are  located  primarily  in the Gulf of  Mexico  and the
onshore  Gulf  Coast.  Other than  accounts  payable and  accrued  plugging  and
abandonment costs, KRE has no debt.

     Jack Hunt and  William J.  Gardiner,  officers of King  Ranch,  Inc.,  were
appointed to St.  Mary's Board of Directors  pursuant to the terms of the merger
agreement.  Also, Robert L. Nance has been appointed to replace Richard C. Kraus
on St. Mary's Board.

     Tom Congdon,  Chairman of St. Mary,  commented,  "In the third  quarter KRE
produced  over  50  MMCF  equivalent  production  per  day,  or an  increase  of
approximately 60% to St. Mary's third quarter  production rate. In addition,  we
are pleased to have added to our shareholder base sophisticated shareholders who
invest for the long term with the objective of building value."

     Except for  historical  information  herein,  statements  in this  release,
including   information   regarding   the  business  of  the  Company,   may  be
forward-looking  statements.  These statements  involve known and unknown risks,
which may cause the Company's  actual results to differ  materially from results
expressed or implied by the  forward-looking  statements.  Statements  including
factors  such as  uncertainties  in cash flow,  expected  merger  benefits,  the
volatility and level of oil and natural gas prices, production rates and reserve
replacement,  reserve estimates,  drilling and operating risks, competition, the
impact of the year 2000 computer issue,  litigation,  environmental matters, the
potential  impact  of  government  regulations,   and  other  such  matters  are
forward-looking statements.