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                                                                     EXHIBIT 4.3

                           CERTIFICATE OF DESIGNATION

                                       OF

                            SERIES D PREFERRED STOCK

                                       OF

                            3TEC ENERGY CORPORATION

                          ____________________________

                            PURSUANT TO SECTION 151
            OF THE GENERAL CORPORATION LAW OF THE STATE OF DELAWARE

                          ____________________________


     3TEC ENERGY CORPORATION, a corporation existing under the laws of the State
of Delaware (the "Corporation"), DOES HEREBY CERTIFY that, pursuant to the
authority conferred on the Board of Directors of the Corporation by the
Certificate of Incorporation of the Corporation (the "Certificate of
Incorporation") and in accordance with Section 151 of the General Corporation
Law of the State of Delaware ("DGCL"), the Board of Directors of the Corporation
on December 20, 1999, duly adopted the following resolution establishing and
creating an additional series of its Preferred Stock, par value $.02 per share,
designated "Series D Preferred Stock":

          RESOLVED, that pursuant to the authority vested in the Board of
     Directors of the Corporation (the "Board of Directors") in accordance with
     the provisions of its Certificate of Incorporation (the "Certificate of
     Incorporation"), an additional series of Preferred Stock, par value $0.02
     per share, of the Corporation is hereby created, and the designation and
     number of shares thereof and the preferences, limitations and relative
     rights thereof are as follows:

     SECTION 1.     DESIGNATION, NUMBER OF SHARES AND STATED VALUE OF SERIES D
PREFERRED STOCK. There is hereby authorized and established a series of
Preferred Stock that shall be designated as "Series D Preferred Stock"
(hereinafter referred to as "Series D Preferred Stock"), and the number of
shares constituting such series shall be 725,167. Such number of shares may be
increased or decreased, but not to a number less than the number of shares of
Series D Preferred Stock then issued and outstanding, by resolution adopted by
the full Board of Directors. The initial "Stated Value" per share of the Series
D Preferred Stock shall be $24.00 per share.

     SECTION 2.     DEFINITIONS.  In addition to the definitions set forth
elsewhere herein, the following terms shall have the meanings indicated:
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     "BUSINESS DAY" shall mean any day other than a Saturday or Sunday, on which
commercial banks are open for business with the public in Houston, Texas.

     "BYLAWS" shall mean the bylaws of the Corporation, certified by the
secretary of the Corporation.

     "COMMON STOCK" shall mean the common stock, $0.02 par value per share, of
the Corporation.

     "JUNIOR SECURITIES" shall mean the Common Stock or any other series of
stock issued by the Corporation ranking junior as to the Series D Preferred
Stock upon liquidation, dissolution or winding up of the Corporation.

     "PARITY STOCK" shall mean the Corporation's Series B Preferred Stock and
Series C Preferred Stock.

     "PERSON" shall mean any individual, corporation, association, partnership,
joint venture, limited liability company, trust, estate, or other entity or
organization, other than the Corporation, any subsidiary of the Corporation, any
employee benefit plan of the Corporation or any subsidiary of the Corporation,
or any entity holding shares of Common Stock for or pursuant to the terms of any
such plan.

     "SERIES B PREFERRED STOCK" shall mean that preferred stock designated as
such by the Corporation pursuant to a Certificate of Designation of Series B
Preferred Stock filed with the Secretary of State of Delaware on November 24,
1999, and having a stated value of $7.50 per share.

     "SERIES C PREFERRED STOCK" shall mean that preferred stock designated as
such by the Corporation pursuant to a Certificate of Designation of Series C
Preferred Stock filed with the Secretary of State of Delaware on November 24,
1999, and having a stated value of $5.00 per share.

     SECTION 3.  CONVERSION AND ANTI-DILUTION.

          (a) Conversion

          (i) Any holder of Series D Preferred Stock may convert all or any
portion of shares of Series D Preferred Stock held by such holder into Common
Stock at any time at its sole option at a ratio of one share of Common Stock for
each share of Series D Preferred Stock.  Any conversion will be deemed effective
at the close of business on the date which the certificate or certificates
representing the shares of Series D Preferred Stock to be converted have been
delivered by the holder to the Corporation at its principal office, together
with a request for conversion of such shares of Series D Preferred Stock.

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          (ii) As soon as possible after a conversion has been effected, the
Corporation will deliver to the holder of shares of Series D Preferred Stock
being converted a certificate or certificates representing the number of shares
of Common Stock issuable by reason of such conversion in such name or names and
such denomination or denominations as the converting holder has specified, and a
certificate representing any shares of Series D Preferred Stock which were
represented by the certificates or certificates delivered to the Corporation in
connection with such conversion but which were not converted.

     (b)  Anti-Dilution Provisions

          (i) In the event that the Common Stock hereafter is changed into or
exchanged for or entitled to receive a different number or kind of shares or
other securities of the Corporation or of another corporation by reason of
merger, consolidation, other reorganization, recapitalization, reclassification,
combination of shares, stock split-up or stock dividend:

              (1) the aggregate number and kind of shares subject to conversion
                  rights hereunder shall be adjusted appropriately;

              (2) conversion rights granted hereunder, both as to the number of
                  subject shares of Series D Preferred Stock and the Conversion
                  Price, shall be adjusted appropriately;

              (3) where dissolution or liquidation of the Corporation or any
                  merger or combination in which the Corporation is not a
                  surviving corporation is involved, each outstanding conversion
                  right granted hereunder shall terminate, but the holder shall
                  have the right, immediately prior to such dissolution,
                  liquidation, merger or combination, to exercise such holder's
                  conversion right, in whole or in part, to the extent it shall
                  not have been exercised;

              (4) such new or additional or different shares or securities which
                  are distributed to a holder, in its capacity as the owner of
                  Common Stock issued pursuant to the conversion rights granted
                  hereunder shall be subject to all of the conditions and
                  restrictions applicable to Common Stock issuable hereunder.

              (5) The foregoing adjustments and the manner of application of the
                  foregoing provisions shall be determined solely by the
                  Corporation. No fractional share of Common Stock shall be
                  issued upon conversion of the shares of Series D Preferred
                  Stock, and any such adjustment may provide for the elimination
                  of fractional shares. Instead of a fractional interest in a
                  share of Common Stock that would otherwise be deliverable upon
                  the conversion of shares of

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                  Series D Preferred Stock, the Corporation shall pay to the
                  holder of such shares an amount in cash based upon the current
                  market price of the Common Stock on the trading day
                  immediately preceding the date of conversion. If more than one
                  share shall be surrendered for conversion at one time by the
                  same holder, the number of full shares of Common Stock
                  issuable upon conversion thereof shall be computed on the
                  basis of the aggregate number of full shares of Common Stock
                  issuable upon conversion thereof.

     SECTION 4.     DIVIDENDS AND DISTRIBUTIONS.

             (a) The holders of Series D Preferred Stock will be entitled to
     receive, as and when declared by the Corporation, out of funds legally
     available for the payment of dividends, dividends at the time and at the
     rates provided for in this Section 4.  Dividends on shares of the Series D
     Preferred Stock shall be cumulative and shall accrue from and including the
     date of issuance of such shares and to and including the date on which such
     shares shall have been redeemed pursuant to Section 7 hereof.   Such
     dividends shall accrue whether or not there shall be (at the time such
     dividend becomes payable or at any other time) profits, surplus or other
     funds of the Corporation legally available for the payment of dividends.
     Except as provided below, the dividends shall be payable in cash.

             (b) Dividends shall accrue on each outstanding share of Series D
     Preferred Stock at the rate of five percent (5%) per annum of the Stated
     Value (the "Dividend Rate") of such share.  Dividends shall be payable
     semi-annually, in arrears, on September 30 and March 31 of each year (each,
     a "Dividend Payment Date"), commencing on March 31, 2000, except that if
     such Dividend Payment Date is not a Business Day, then such dividend shall
     be payable on the first Business Day immediately thereafter to the holders
     of the Series D Preferred Stock.  Dividends payable on the Series D
     Preferred for each full semi-annual period shall be computed by dividing
     the Dividend Rate by two (2).  Dividends payable on the Series D Preferred
     Stock for any period that is shorter or longer than a full semi-annual
     period shall be computed on the basis of a 360-day year comprised of two
     semi-annual 180-day periods.

             (c) With respect to the first six (6) semi-annual dividends payable
     under this Section 4 commencing with the first Dividend Payment Date, the
     Corporation may, at least 30 days prior to the subject Dividend Payment
     Date, elect to pay the cash dividend payable on such Dividend Payment Date
     to the holders of Series D Preferred Stock in shares of Series D Preferred
     Stock (a "Payment in Kind").  If such an election is made, the Corporation
     shall promptly notify the holders of the Series D Preferred Stock of (i)
     the election to make a Payment in Kind in lieu of a payment in cash for the
     subject Dividend Payment Date.  An election for any particular Dividend
     Payment Date shall operate only for such Dividend Payment Date.  Each
     Payment in Kind shall be payable as of the Dividend Payment Date for which
     the election to make such Payment in Kind was made, except that if such
     Dividend

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     Payment Date is not a Business Day, then such Payment in Kind shall be on
     the first Business Day immediately thereafter to the holders of the Series
     D Preferred Stock.

          (d) Each Payment in Kind shall be equal to that number of additional
     shares of Series D Preferred Stock that is equal to A divided by B where:

               "A" = 100% of the aggregate dollar amount of the cash dividends
          payable on any such Dividend Payment Date; and

               "B" = the Stated Value.

          Certificates representing the shares of Series D Preferred Stock
     issuable on payment of any Payment in Kind shall be delivered to each
     holder entitled to receive such Payment in Kind (in appropriate
     denominations) on or before the forty-fifth (45/th/) day following the
     Dividend Payment Date for which such Payment in Kind is elected to be paid
     hereunder. Shares of Series D Preferred Stock issued on payment of any
     Payment in Kind shall be duly authorized, validly issued and nonassessable
     and, upon issuance, shall have rights (including without limitation,
     dividend, voting and redemption rights) and a Stated Value identical to the
     outstanding shares of Series D Preferred Stock in respect of which they are
     issued.

          (e) To the extent dividends are not paid in cash or in kind on a
     Dividend Payment Date, all dividends which shall have accrued on each share
     of Series D Preferred Stock outstanding as of such Dividend Payment Date
     shall be added to the Stated Value of each such share of Series D Preferred
     Stock and shall remain a part thereof until paid, and dividends shall
     accrue at the Dividend Rate and be paid on such share of Series D Preferred
     Stock on the basis of the Stated Value, as so adjusted.

          (f) Dividends payable on each Dividend Payment Date shall be paid to
     record holders of the shares of Series D Preferred Stock as they appear on
     the books of the Corporation at the close of business on the tenth Business
     Day immediately preceding the respective Dividend Payment Date or on such
     other record date as may be fixed by the Board of Directors of the
     Corporation in advance of a Dividend Payment Date, provided that no such
     record date shall be less than ten nor more than sixty calendar days
     preceding such Dividend Payment Date.

   SECTION 5. CERTAIN COVENANTS AND RESTRICTIONS.  So long as any shares
of Series D Preferred Stock are outstanding, the Corporation shall not, without
the affirmative consent or approval of the holders of a majority of the issued
and outstanding shares of the Series D Preferred Stock:

          (i) in any manner authorize, create, designate or issue any class or
     series of capital stock of the Corporation (including any shares of
     treasury stock) or rights, options,

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     warrants or other securities convertible into or exercisable or
     exchangeable for capital stock or any debt security which by its terms is
     convertible into or exchangeable for any equity security or has any other
     equity participation feature or any security that is a combination of debt
     and equity, which, in each case as to the equity or convertible component
     thereof, as to the payment of dividends, distribution of assets or
     redemptions, including, without limitation, distributions to be made upon
     the liquidation, dissolution or winding up of the Corporation or a merger,
     consolidation or sale of the assets thereof, is senior to the Series D
     Preferred Stock;

          (ii) reclassify any securities of the Corporation into shares of any
     class or series of capital stock of the Corporation (A) ranking, either as
     to payment of dividends, distributions of assets or redemptions, including,
     without limitation, distributions to be made upon the liquidation,
     dissolution or winding up of the Corporation or a merger, consolidation or
     sale of the assets thereof, senior to the Series D Preferred Stock or (B)
     which in any manner adversely affects the rights of the holders of Series D
     Preferred Stock in their capacity as such;

          (iii)  increase the authorized number of shares of Series D Preferred
     Stock;

          (iv) issue any additional shares of Series D Preferred Stock other
     than as contemplated by Section 4 of this Certificate of Designation;

          (v)  reclassify, cancel or in any manner alter or change the terms,
     designations, powers, preferences or relative, optional or other special
     rights, or the qualifications, limitations or restrictions thereof, of the
     Series D Preferred Stock; or

          (vi) amend, repeal or modify (whether by merger, consolidation, or
     otherwise) any provision of this Certificate of Designation or the
     Certificate of Incorporation or Bylaws in a manner that adversely affects
     the powers, preferences or rights of the Series D Preferred Stock.

   SECTION 6.  LIQUIDATION PREFERENCE.

          (a) In the event of any liquidation, dissolution, or winding-up of the
     Corporation (in connection with the bankruptcy or insolvency of the
     Corporation or otherwise), whether voluntary or involuntary, before any
     payment or distribution of the assets of the Corporation (whether capital
     or surplus) shall be made to or set apart for the holders of shares of any
     Junior Securities, the holders of the shares of Series D Preferred Stock
     shall be entitled to receive an amount per share equal to the Stated Value
     per share held by them plus an amount equal to the aggregate dollar amount
     of all accrued and unpaid dividends that have not been added to the Stated
     Value of such shares.  If, upon the occurrence of a liquidation,
     dissolution, or winding up, the assets and funds thus distributed among the
     holders of the Series D Preferred Stock and the Parity Stock shall be
     insufficient to permit the payment to

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     such holders of their full liquidation preferences, then the entire assets
     and funds of the Corporation legally available for distribution to the
     holders of capital stock shall be distributed, ratably to the holders of
     the shares of Series D Preferred Stock and the Parity Stock on a pro rata
     basis in the proportion that the amount each holder is entitled to receive
     pursuant to its liquidation rights bears to the total amount available for
     payment to the holders of Series D Preferred Stock and Parity Stock upon
     liquidation.

          (b)   If assets are remaining after payment of the full liquidation
     preference with respect to the Series D Preferred Stock and the Parity
     Stock set forth in subsection (a) above, then the holders of any other
     class or series of preferred stock, if any, shall be entitled to their
     respective preferential amounts on liquidation, and thereafter the holders
     of the Common Stock shall be entitled to share ratably in all such
     remaining assets and surplus funds in the proportion that each holder's
     shares bears to the total number of shares of Common Stock outstanding.

          (c)   For purposes of this Section 6, the holders of a majority of the
     Series D Preferred Stock then outstanding, voting together as a class may
     elect to have treated as a liquidation, dissolution or winding up of the
     Corporation, the consolidation or merger of the Corporation with or into
     any other corporation or the sale or other transfer in a single transaction
     or a series of related transactions of all or substantially all of the
     assets of the Corporation, or any other reorganization of the Corporation.

          (d)   Written notice of any liquidation, dissolution or winding-up of
     the Corporation, stating the payment date or dates when and the place or
     places where the amounts distributable in such circumstances shall be
     payable, shall be given by first class mail, postage prepaid, not less than
     15 days prior to any payment date stated therein, to the holders of record
     of the shares of Series D Preferred Stock and the Parity Stock at their
     respective addresses as the same shall appear in the records of the
     Corporation.

     SECTION 7. REDEMPTION.

            (a) The outstanding shares of Series D Preferred Stock are subject
to redemption in accordance with the following provisions:

                (i)  At any time, the Corporation may redeem all of the shares
     of Series D Preferred Stock outstanding on such date (the "Series D
     Redemption Date") with a thirty-day prior written notice.

                (ii) The redemption price per share for Series D Preferred Stock
     redeemed on the Series D Redemption Date (the "Series D Redemption Price")
     shall be equal to the Stated Value per share of the shares to be redeemed
     plus an amount equal to the aggregate dollar amount of all accrued and
     unpaid dividends through the Series D Redemption Date that have not been
     added to the Stated Value of such shares.  The Series D Redemption Price
     shall be paid in cash from any source of funds legally available therefor.

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               (iii)  On or after the Series D Redemption Date, each holder of
     shares of Series D Preferred Stock shall surrender his certificate or
     certificates for such shares to the Corporation at the place designated in
     the redemption notice and shall thereupon be entitled to receive payment of
     the Series D Redemption Price.

               (iv)   If pursuant to Paragraph 7(a)(i), the Corporation shall
     redeem any shares of Series D Preferred Stock, the Corporation shall give
     written notice of such redemption to each holder of record of Series D
     Preferred Stock to be redeemed not less than thirty (30) days prior to the
     date fixed for redemption, by certified mail enclosed in a postage-paid
     envelope addressed to such holder at such holder's address as the same
     shall appear on the books of the Corporation.  Such notice shall (i) state
     that the Corporation has elected to redeem such shares of Series D
     Preferred Stock, (ii) state the date fixed for redemption, (iii) state the
     Series D Redemption Price and (iv) call upon such holder to surrender to
     the Corporation on or after said date at its principal place of business
     designated in such notice a certificate or certificates representing the
     number of Series D Preferred Stock to be redeemed in accordance with such
     notice.  On or after the date fixed in such notice for redemption, each
     holder of shares of Series D Preferred Stock to be so redeemed shall
     present and surrender the certificate or certificates for such shares of
     Series D Preferred Stock to the Corporation at the place designated in said
     notice, and thereupon the Series D Redemption Price shall be paid to, or to
     the order of, the Person whose name appears on such certificate or
     certificates as the owner thereof.  From and after the date fixed in any
     such notice as the date for redemption, unless default shall be made by the
     Corporation in providing for the payment of the Series D Redemption Price
     pursuant to such notice, all rights of the holders of the shares of Series
     D Preferred Stock so redeemed, except the right to receive the Series D
     Redemption Price (but without interest thereon), shall cease and terminate.
     If less than all of the outstanding shares of Series D Preferred Stock are
     to be redeemed, the shares of Series D Preferred Stock to be redeemed shall
     be allocated among the holders thereof in proportion to the respective
     number of shares of Series D Preferred Stock held by them.

     SECTION 8. REACQUIRED SHARES.  Subject to the terms of this Certificate
of Designation, any shares of Series D Preferred Stock repurchased, redeemed or
otherwise acquired by the Corporation shall be retired and canceled promptly
after the acquisition thereof.  All such shares shall upon their cancellation
become authorized but unissued shares of Preferred Stock, without designation as
to series, and may thereafter be reissued (but may not be reissued as additional
shares of Series D Preferred Stock).

     SECTION 9. VOTING RIGHTS.

          (a)   Except as otherwise provided in this Section 9 or required by
     law or any provision of the Certificate of Incorporation, the holders of
     the shares of Series D Preferred Stock shall not have any voting rights.

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          (b) Pursuant to Section 228 of the DGCL, any action of the holders of
     the Series D Preferred Stock, voting as a separate class, which is required
     by the DGCL to be taken at any annual or special meeting of the holders of
     the Series D Preferred Stock, or is otherwise permitted to be taken by the
     holders of the Series D Preferred Stock at any annual or special meeting
     pursuant to the DGCL, the Certificate of Incorporation (including this
     Certificate of Designation) or the Bylaws, may be taken without a meeting,
     without prior notice, and without a vote, if a consent or consents in
     writing, setting forth the action so taken, shall be signed by the holder
     or holders of shares of the Series D Preferred Stock, having not less than
     the minimum number of votes that would be necessary to take such action at
     a meeting at which the holders of all shares of the Series D Preferred
     Stock were present and voted.

     SECTION 10.  RANKING.  The Series D Preferred Stock and the Parity Stock
shall rank senior to the Common Stock upon liquidation, dissolution or winding
up of the Corporation.  Without limiting the definition of Junior Securities,
the shares of Common Stock shall rank junior to the Series D Preferred Stock and
the Parity Stock with respect to the payments required or permitted to be made
to the holders thereof and payments required to be made to the holders of the
Series D Preferred Stock and the Parity Stock pursuant hereto.

     SECTION 11.  RECORD HOLDERS.  The Corporation may deem and treat the
record holder of any shares of Series D Preferred Stock as the true and lawful
owner thereof for all purposes, and the Corporation shall not be affected by any
notice to the contrary.

     SECTION 12.  NOTICE.  Except as may otherwise be provided by law or
provided for herein, all notices referred to herein shall be in writing, and all
notices hereunder shall be deemed to have been given upon the earlier of receipt
of such notice or three (3) Business Days after the mailing of such notices sent
by Registered Mail (unless first-class mail shall be specifically permitted for
such notice under the terms hereof) with postage prepaid, addressed:  If to the
Corporation, to its principal executive offices (Attention: Corporate Secretary)
or to any agent of the Corporation designated as permitted hereby; or if to a
holder of the Series D Preferred Stock, to such holder at the address of such
holder of the Series D Preferred Stock as listed in the stock record books of
the Corporation, or to such other address as the Corporation or holder, as the
case may be, shall have designated by notice similarly given.

     SECTION 13.  SUCCESSORS AND TRANSFEREES.  The provisions applicable to
shares of Series D Preferred Stock shall bind and inure to the benefit of and be
enforceable by the Corporation, the respective successors to the Corporation,
and by any record holder of shares of Series D Preferred Stock.

          RESOLVED FURTHER, that the appropriate officers of the Corporation be,
     and they are hereby, authorized and directed from time to time to execute
     such certificates, instruments or other documents and do all such things as
     may be necessary or advisable in their discretion in order to carry out the
     terms hereof, including the filing with the Secretary of State for the
     State of Delaware of a copy of the foregoing resolution executed by an
     officer of the Corporation.

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Dated: February 2, 2000.

                                3TEC ENERGY CORPORATION


                                By: ___________________________________
                                    Name:   Floyd C. Wilson
                                    Title:     President




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