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Exhibit 10.4

CERTIFICATE OF DESIGNATION,
PREFERENCES, RIGHTS AND LIMITATIONS
of
SERIES B 8% AUTOMATICALLY CONVERTIBLE PREFERRED STOCK
of
PETROHAWK ENERGY CORPORATION

Pursuant to Section 151 of the Delaware General Corporation Law

        Petrohawk Energy Corporation, a Delaware corporation (the
"Corporation"), certifies that pursuant to the authority contained in its
Certificate of Incorporation, and in accordance with the provisions of
Section 151 of the Delaware General Corporation Law (the "DGCL"), its Board of
Directors (the "Board") has adopted the following resolution creating a series
of Preferred Stock, par value $0.001 per share, designated as Series B 8%
Automatically Convertible Preferred Stock:

        RESOLVED, that a series of the class of authorized $0.001 par value
Series B Preferred Stock of the Corporation is hereby created, and that the
designation and amount thereof and the voting powers, preferences and relative,
participating, optional and other special rights of the shares of such series,
and the qualifications, limitations or restrictions thereof are as follows:

        1.     Designation and Amounts.

        The shares of such series shall be designated as the "Series B 8%
Automatically Convertible Preferred Stock" (the "Series B Preferred") and the
number of shares initially constituting such series shall be 2,580,645, which
number may be decreased (but not increased) by the Board without a vote of the
stockholders; provided, however, that such number may not be decreased below the
number of then currently outstanding shares of Series B Preferred and shares of
Series B Preferred issuable on exercise of rights to acquire Series B Preferred.

        2.     Rank.

        The Series B Preferred shall rank senior to the $0.001 par value common
stock ("Common Stock") of the Corporation, any other preferred stock of the
Corporation issued and outstanding on the date the first share of Series B
Preferred is issued (other than the 8% Preferred), or any other series of stock
issued by the Corporation ranking junior as to the Series B Preferred with
respect to payment of dividends, or upon liquidation, dissolution or winding up
of the Corporation (collectively, "Junior Securities"). The Series B Preferred
shall rank junior to all Senior Securities with respect to both the payment of
dividends and the distribution of assets on liquidation, winding up and
dissolution. "Senior Securities" means any class or series of stock issued by
the Corporation ranking senior to the Series B Preferred with respect to payment
of dividends, or upon liquidation, dissolution or winding up of the Corporation.
The Corporation's 8% Cumulative Convertible Preferred Stock (the "8% Preferred")
is expressly made a Senior Security.

        3.     Dividends.

        (a)   Commencing April 1, 2005, the holders of the Series B Preferred
shall be entitled to receive out of any assets legally available therefor
cumulative dividends on each outstanding share of Series B Preferred at the rate
of 8% of the Initial Liquidation Price, as described in Section 4(a), per share
per annum from the original issue date of the Series B Preferred (the "Issue
Date"), payable quarterly in cash within 15 days following the end of the
calendar quarters ending March 31, June 30, September 30 and December 31 of each
year (each a "Dividend Payment Date"), when and as declared by the Board, in
accordance with the preference and priority described in Section 2 with respect
to any payment of

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any dividend on the Common Stock, the 8% Preferred or any other class or series
of stock of the Corporation. Such dividends shall be cumulative from the Issue
Date, whether or not in any period the Company is legally permitted to make the
payment of such dividends and whether or not such dividends are declared, and
shall be payable when, as and if declared by the Board. All dividends on the
Series B Preferred shall accrue on a daily basis from the Issue Date whether or
not there are (at the time such dividend accrues or becomes payable or at any
other time) profits, surplus or other funds of the Corporation legally available
for the payment of dividends. Neither conversion on or after April 1, 2005 nor
redemption of the Series B Preferred on or after April 1, 2005 shall affect any
holder's right to receive any accrued but unpaid dividends on such Series B
Preferred. Notwithstanding any other provision herein, no dividends shall be
payable on the Series B Preferred if conversion, as described in Section 5,
occurs on or before March 31, 2005.

        (b)   Dividends shall be calculated on the basis of the time elapsed
from and including the Issue Date to and including the Dividend Payment Date or
on any final distribution date relating to conversion or redemption or to a
dissolution, liquidation or winding up of the Corporation. Dividends payable on
the shares of Series B Preferred for any period of less than a full calendar
year shall be prorated for the partial year on the basis of a 360-day year of
twelve, 30-day months.

        (c)   To the extent dividends are not paid on a Dividend Payment Date,
all dividends that have accrued on each share of Series B Preferred outstanding
as of such Dividend Payment Date shall accrue additional dividends and all such
accrued and unpaid dividends shall compound on a quarterly basis at a rate per
annum equal to 12% (the "Default Rate"). Except as provided in the preceding
sentence, (i) no interest, or sum of money in lieu of interest, shall be payable
in respect of any dividend payment or payments on the Series B Preferred that
are in arrears, and (ii) the dividend rate specified in Section 3(a) shall
continue in effect.

        (d)   Dividends payable on each Dividend Payment Date shall be paid to
record holders of the shares of Series B Preferred as they appear on the
Corporation's books 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 in advance of a Dividend Payment Date,
provided that no such record date shall be less than ten nor more than 60
calendar days preceding such Dividend Payment Date. Dividends in arrears may be
declared and paid at any time to holders of record on a date not more than 60
calendar days preceding the payment date as may be fixed by the Board. Dividends
paid on shares of Series B Preferred in an amount less than the total amount of
such dividends at the time payable shall be allocated pro rata on a share by
share basis among all shares outstanding. "Business Day" means any day other
than a Saturday, Sunday or a day on which banking institutions in New York, New
York are authorized or obligated by law or executive order to close.

        (e)   So long as any shares of Series B Preferred are outstanding, no
dividend or other distribution, whether in liquidation or otherwise, shall be
declared or paid, or set apart for payment on or in respect of, any Junior
Securities, nor shall any Junior Securities be redeemed, purchased or otherwise
acquired for any consideration prior to the stated maturity thereof (or any
money be paid to a sinking fund or otherwise set apart for the purchase or
redemption of any such Junior Securities), without the prior consent of the
holders of a majority of the outstanding shares of Series B Preferred voting
together as a separate class. So long as any shares of Series B Preferred are
outstanding and without the prior consent of the holders of a majority of the
outstanding shares of Series B Preferred voting together as a separate class, no
dividend or other distribution, whether in liquidation or otherwise, shall be
declared or paid, or set apart for payment on or in respect of, any Parity
Securities, nor shall any Parity Securities be redeemed, purchased or otherwise
acquired for any consideration prior to the stated maturity thereof (or any
money be paid to a sinking fund or otherwise set apart for the purchase or
redemption of any such Parity Securities), unless (i) if there are any accrued
and unpaid dividends on the Series B Preferred or such Parity Stock, such
dividend or distribution shall be allocated to pay such accrued and unpaid
dividends of the Series B Preferred and such Parity Stock, pro rata based on the

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amount of such accrued and unpaid dividends and (ii) if all accrued and unpaid
dividends have been paid on the Series B Preferred and such Parity Stock, such
dividends and distributions shall be allocated pro rata to the holders of the
Series B Preferred and the Parity Stock based on the respective liquidation
preferences thereof. "Parity Security" means the Series B Preferred or any other
class or series of stock issued by the Corporation ranking on a parity with the
Series B Preferred with respect to payment of dividends, and upon liquidation,
dissolution or winding up of the Corporation.

        4.     Liquidation Preference.

        (a)   Distribution Amount. In the event of any liquidation, dissolution
or winding up of the Corporation, either voluntary or involuntary, the holders
of the Series B Preferred shall be entitled to receive, in accordance with the
preference and priority described in Section 2 as to any distribution of any
assets of the Corporation to the holders of any other class or series of shares,
the amount of $77.50 per share of Series B Preferred (the "Initial Liquidation
Price") plus any accrued but unpaid dividends and any cumulated dividends
thereon (together the "Liquidation Preference"). To the extent the available
assets are insufficient to fully satisfy the Liquidation Preference, then the
holders of the Series B Preferred shall share ratably in such distribution in
the proportion that each holder's shares bears to the total number of shares of
Series B Preferred outstanding. No payment on account of any such liquidation,
dissolution or winding up of the Company shall be paid to the holders of the
shares of Series B Preferred or the holders of any Parity Securities unless
there shall be paid at the same time to the holders of the shares of Series B
Preferred and the holders of any Parity Securities amounts in proportion to the
respective full preferential amounts to which each is entitled with respect to
such distribution. For this Section 4(a), absent the consent of holders of
662/3% of the Series B Preferred, a Change of Control or the consummation of a
Qualified Offering shall be deemed to be a liquidation, dissolution or
winding-up of the Company. "Change of Control" means (A) the acquisition at any
time by a "person" or "group" (as such terms are used in Sections 13(d) and
14(d)(2) of the Securities Exchange Act of 1934 (the "Exchange Act")) who or
which is the beneficial owner (as defined in Rule 13(d)-3 under the Exchange
Act), directly or indirectly, of securities representing more than 35% of the
combined voting power in the election of directors of the then outstanding
securities of the Corporation or any successor of the Corporation; (B) approval
by the Corporation or any of its subsidiaries of any sale or disposition of
substantially all of the assets or earning power of the Corporation and its
subsidiaries, taken as a whole; or (C) approval by the stockholders of the
Corporation of any merger, consolidation or statutory share exchange to which
the Corporation is a party as a result of which the persons who were
stockholders immediately prior to the effective date of the merger,
consolidation or share exchange shall have beneficial ownership of less than 50%
of the combined voting power in the election of directors of the surviving
corporation. "Qualified Offering" means an offering for cash by the Corporation
of Junior Securities.

        (b)   After payment of the full amount payable to the holders of
Series B Preferred pursuant to Section 4(a), and subject to the rights of
holders of Junior Securities other than the Common Stock, the holders of Common
Stock shall share in the distribution of the remaining available assets of the
Company under the Company's Certificate of Incorporation.

        (c)   Written notice of any liquidation, dissolution or winding up of
the Company, 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 fifteen days prior to
any payment date stated therein, to the holders of record of the shares of
Series B Preferred at their respective addresses as the same shall appear in the
records of the Company.

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        5.     Conversion.

        The Series B Preferred shall be convertible into Common Stock in
accordance with the following:

        (a)   Automatic Conversion. The Series B Preferred shall automatically
convert into Common Stock on the day (the "Conversion Date") immediately
following the expiration of the twenty calendar day period set forth in
Rule 14c-2(b) under the Exchange Act, such period commencing on the distribution
to the Corporation's stockholders in accordance Regulation 14C promulgated under
the Exchange Act of an Information Statement on Schedule 14C filed by the
Corporation with the Securities and Exchange Commission relating to the issuance
of Common Stock in connection with the conversion of the Series B Preferred.
Each share of Series B Preferred shall be convertible into such number of fully
paid and non-assessable shares of Common Stock as is determined by dividing
(i) the Liquidation Preference of the Series B Preferred determined pursuant to
Section 4, by (ii) the Conversion Price determined as hereinafter provided in
effect on the Conversion Date. Each share of Series B Preferred shall thus at
the date of original issuance be convertible into ten shares of Common Stock,
subject to adjustment as set forth herein. Upon the automatic conversion of the
Series B Preferred, (i) each holder shall be deemed to own the number of shares
of Common Stock into which the holder's Series B Preferred is converted and
(ii) the Corporation shall pay in cash all accrued and unpaid dividends, if any,
through the Conversion Date. Promptly thereafter the holder shall surrender the
certificate or certificates representing the Series B Preferred which were
converted at the office of the Corporation or of the transfer agent for such
shares, or at such other place designated by the Corporation. Such surrender may
be made by registered mail with return receipt requested, properly insured, by
hand or by overnight courier. The Corporation shall, promptly upon receipt of
such certificates representing the Series B Preferred shares which have been
converted, deliver to such holder, a certificate or certificates for the number
of shares of Common Stock to which such holder shall be entitled. At the close
of business on the Conversion Date, each holder shall be deemed to be the
beneficial owner of the shares of Common Stock, and the Series B Preferred
theretofore held by such holder shall no longer be outstanding.

        (b)   Determination of Conversion Price. The Conversion Price (the
"Conversion Price") shall be $7.75. If the Corporation at any time or from time
to time makes, issues, declares, pays or fixes a record date for the
determination of holders entitled to receive any dividend or other distribution
payable of shares of Common Stock in Common Stock or other securities of the
Corporation or any of its subsidiaries or in rights to acquire Common Stock or
other securities of the Corporation or any of its subsidiaries, or shall effect
a stock split or reverse stock split, or a combination, consolidation or
reclassification of the Common Stock, then in each such event the Conversion
Price shall be proportionately decreased or increased, as appropriate, to give
effect to such event, such that upon any conversion after any such event, a
holder of Series B Preferred shall be entitled to receive the number and class
of any securities of the Corporation or other assets which the holder would have
received had the Series B Preferred been converted into Common Stock immediately
before the event.

        (c)   Certificates as to Adjustments. Upon the occurrence of any
adjustment or readjustment of the Conversion Price pursuant to Section 5(b), the
Corporation at its expense shall promptly compute such adjustment or
readjustment in accordance with the terms hereof and the principal financial
officer of the Corporation shall verify such computation and prepare and furnish
to each holder of Series B Preferred a certificate setting forth such adjustment
or readjustment and showing in detail the facts upon which such adjustment or
readjustment is based. The Corporation shall, upon the written request at any
time of any holder of Series B Preferred, furnish or cause to be furnished to
such holder a like certificate prepared by the Corporation setting forth
(i) such adjustments and readjustments and (ii) the number of other securities
and the amount, if any, of other property which at the time would be received
upon the conversion of Series B Preferred with respect to each share of Common
Stock received upon such conversion.

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        (d)   Notice of Record Date. If the Corporation takes a record of the
holders of any class of securities for the purpose of determining the holders
thereof who are entitled to receive any dividend (other than a cash dividend) or
other distribution, any security or right convertible into or entitling the
holder thereof to receive additional shares of Common Stock, or any right to
subscribe for, purchase or otherwise acquire any shares of stock of any class or
any other securities or property, or to receive any other right, the Corporation
shall mail to each holder of Series B Preferred at least ten days prior to the
date specified therein, a notice specifying the date on which any such record is
to be taken for the purpose of such dividend, distribution, security or right
and the amount and character of such dividend, distribution, security or right.

        (e)   Issue Taxes. The Corporation shall pay any and all issue and other
taxes, excluding any income, franchise or similar taxes, that may be payable in
respect of any issue or delivery of shares of Common Stock on conversion of
shares of Series B Preferred; provided, however, that the Corporation shall not
be obligated to pay any transfer taxes resulting from any transfer requested by
any holder in connection with any such conversion.

        (f)    Reservation of Stock Issuable Upon Conversion. The Corporation
shall at all times reserve and keep available out of its authorized but unissued
shares of Common Stock, solely for the purpose of effecting the conversion of
the shares of the Series B Preferred, such number of its shares of Common Stock
as shall from time to time be sufficient to effect the conversion of all
outstanding shares of the Series B Preferred, and if at any time the number of
authorized but unissued shares of Common Stock shall not be sufficient to effect
the conversion of all then outstanding shares of the Series B Preferred, the
Corporation will take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of Common
Stock to such number of shares as shall be sufficient for such purpose,
including, without limitation, engaging in best efforts to obtain the requisite
stockholder approval.

        (g)   Fractional Shares. No fractional shares shall be issued upon the
conversion of any share or shares of Series B Preferred. All shares of Common
Stock (including fractions thereof) issuable upon conversion of more than one
share of Series B Preferred by a holder thereof shall be aggregated for purposes
of determining whether the conversion would result in the issuance of any
fractional share. If, after the aforementioned aggregation, the conversion would
result in the issuance of a fraction of a share of Common Stock, in lieu of
issuing any fractional share, the fraction shall be rounded up or down to the
nearest whole number of shares.

        (h)   Reorganization or Merger. In case of any reorganization or any
reclassification of the capital stock of the Corporation or any consolidation or
merger of the Corporation with or into any other corporation or corporations or
a sale of all or substantially all of the assets of the Corporation to any other
person, and such transaction is not treated as a liquidation, dissolution or
winding up as provided in Section 4, then, as part of such reorganization,
consolidation, merger or sale, provision shall be made so that each share of
Series B Preferred shall thereafter be convertible into the number of shares of
stock or other securities or property (including cash) to which a holder of the
number of shares of Common Stock deliverable upon conversion of such share of
Series B Preferred would have been entitled upon the record date of (or date of,
if no record date is fixed) such event and, in any case, appropriate adjustment
(as determined by the Board of Directors) shall be made in the application of
the provisions herein set forth with respect to the rights and interest
thereafter of the holders of the Series B Preferred, to the end that the
provisions set forth herein shall thereafter be applicable, as nearly as
equivalent as is practicable, in relation to any shares of stock or the
securities or property (including cash) thereafter deliverable upon the
conversion of the shares of Series B Preferred.

        6.     Redemption of Series B Preferred.

        (a)   On February 23, 2009, if any shares of Series B Preferred are then
outstanding, a redemption event ("Redemption Event") shall be deemed to have
occurred.

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        (b)   Within ten days after a Redemption Event, the Corporation shall
mail a written notice (the "Redemption Notice") to each holder of record of the
Series B Preferred at the address last shown on the records of the Corporation
for such holder, notifying such holder of the redemption which is to be
effected, the date on which the redemption of the Series B Preferred shall occur
(which day must be within 30 days of the Redemption Event (the "Redemption
Date"), the place at which payment may be obtained and calling upon each such
holder to surrender to the Corporation, in the manner and at the place
designated, a certificate or certificates representing the total number of
shares of Series B Preferred held by such holder. On or after the Redemption
Date, each holder of Series B Preferred then outstanding shall surrender to the
Corporation the certificate or certificates representing the shares of Series B
Preferred owned by such holder as of the Redemption Date, in the manner and at
the place designated in the Redemption Notice, and thereupon an amount equal to
the Liquidation Preference per share of Series B Preferred shall be payable to
the order of the person whose name appears on such certificate or certificates
as the owner thereof and each surrendered certificate shall be canceled.

        7.    Corporation's Dealings with Holders of Series B Preferred.    No
payments shall be made to holders of Series B Preferred, or redemptions of
Series B Preferred shall be made unless the right to receive such payments or
participate in such redemptions are made available to all holders of Series B
Preferred on a pro rata basis based on the number of shares of Series B
Preferred such holder holds.

        8.    Consent Rights.    The Corporation shall not undertake the
following actions without the approval by the vote or written consent of the
holders of at least 662/3% of the Series B Preferred then outstanding, voting
together as a single class:

        (a)   amend, alter, waive, repeal or modify (whether by merger,
consolidation or otherwise) any provision of the Certificate of Incorporation
(including any filing or amending of a Certificate of Designation for any Senior
Securities or Parity Securities) or Bylaws of the Corporation so as to adversely
affect or otherwise impair any of the rights, preferences, privileges,
qualifications, limitations or restrictions of, or applicable to, the Series B
Preferred;

        (b)   authorize, issue or increase the authorized amount of any class of
Senior Securities (other than issuing shares of the 8% Preferred authorized but
unissued as of the date hereof) or Parity Securities;

        (c)   increase or decrease (other than by redemption or conversion) the
authorized number of shares of Series B Preferred;

        (d)   liquidate, dissolve or wind up the Corporation in any form of
transaction; or

        (e)   enter into any agreement regarding, or any transaction or series
of transactions resulting in, a Change of Control before June 30, 2005, and
thereafter unless provision is made in the agreement effecting such transaction
provide for the redemption of the Series B Preferred under Section 4.

        9.     Voting Rights.

        (a)   No General Voting Rights. Except as otherwise provided herein or
as required by law, the Series B Preferred shall not be entitled to any voting
rights.

        (b)   Board Representation.

        (i)    If the Conversion Date has not occurred by the earlier of the
record date fixed by the Board for the Corporation's annual meeting of
stockholders for 2005 or August 31, 2005, the holders of the Series B Preferred,
exclusively and as a separate class, shall be entitled to elect two members of
the Board. The two directors elected under this Section 9(b) are referred to as
"Preferred Directors". Upon election of the Preferred Directors, the Board shall
increase the size of the Board to add the Preferred Directors.

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        (ii)   The election of the Preferred Directors shall occur (i) at the
annual meeting of stockholders, (ii) at any special meeting of stockholders if
such meeting is called for the purpose of electing directors, (iii) at any
special meeting of holders of shares of Series B Preferred called by holders of
not less than a majority of the outstanding shares of Series B Preferred Stock
or (iv) by the written consent of holders of a majority of the outstanding
shares of Series B Preferred entitled to vote for the Preferred Directors in the
manner and on the basis as otherwise provided by law. At any meeting having as a
purpose the election of the Preferred Directors, the presence, in person or by
proxy, of holders of not less than one-third (1/3) of the outstanding shares of
Series B Preferred Stock shall be required and sufficient to constitute a quorum
of such class for the election of the Preferred Directors. The holders of shares
of Series B Preferred shall be entitled to notice of any stockholders' meeting
in accordance with the Bylaws of the Corporation and notice of any other matter
submitted to the vote of stockholders.

        (iii)  If at any time when any share of Series B Preferred is
outstanding any such Preferred Director should cease to be a Preferred Director
for any reason, the remaining Preferred Director may appoint an additional
Preferred Director to fill the vacancy. If the remaining Preferred Director does
not appoint an additional Preferred Director or if there are no Preferred
Directors, the vacancy(ies) may be filled by the vote or written consent of the
holders of the outstanding shares of Series B Preferred, voting together as a
separate class, in the manner and on the basis specified above or as otherwise
provided by law. Any Preferred Director elected to fill a vacancy shall serve
the same remaining term as that of his or her predecessor, subject, however, to
prior death, resignation, retirement, disqualification, or removal from office.

        (iv)  A Preferred Director may be removed with or without cause by, and
only by, the affirmative vote of the holders of not less than a majority of the
outstanding shares of Series B Preferred, given either at a special meeting of
the holders of Series B Preferred duly called for that purpose, or by written
consent of the holders of Series B Preferred.

        (c)   Calling a Meeting.    The holders of not less than 20% of the
shares of Series B Preferred outstanding may request the calling of a special
meeting of the holders of Series B Preferred, which meeting shall thereupon be
called by the President, a Vice-President or the Secretary of the Corporation.
Notice of such meeting shall be given to each holder of record of Series B
Preferred by mailing a copy of such notice to such holder at such holder's last
address as the same appears on the books of the Corporation. Such meeting shall
be called for a time not earlier than 20 days and not later than 60 days after
such request and shall be held at such place as specified in such request. If
such meeting shall not be called within 20 days after such request, then the
holders of not less than 20% of the shares of Series B Preferred outstanding may
designate in writing any holder of Series B Preferred to call such meeting on
similar notice at the expense of the Corporation. Any holder of Series B
Preferred so designated shall have access to the stock books of the Corporation
relating to Series B Preferred for the purpose of calling a meeting of the
holders pursuant to these provisions.

        (d)   Action Without Meeting.    With respect to actions by the holders
of Series B Preferred upon those matters on which such holders are entitled to
vote as a separate class, such actions may be taken without a stockholders
meeting by the written consent of such holders who would be entitled to vote at
a meeting having voting power to cast not less than the minimum number of votes
that would be necessary to authorize or take such action at a meeting at which
the Series B Preferred is entitled to vote were present and voted.

        10.    Status of Reacquired Shares of Series B Preferred.    Shares of
outstanding Series B Preferred reacquired by the Corporation (including shares
of Series B Preferred which have been redeemed pursuant to the provisions
hereof) or cancelled upon conversion into Common Stock shall have the status of
authorized and unissued shares of Preferred Stock, undesignated as to series,
and subject to later designation and issuance by the Corporation in accordance
with its Certificate of Incorporation.

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        11.    Preemptive Rights.    Holders of Series B Preferred shall not be
entitled to any preemptive, subscription or similar rights in respect to any
securities of the Corporation, except as specifically set forth herein.

        12.    Notices.    Any notice required by the provisions hereof to be
given to the holders of Series B Preferred shall be deemed given if deposited in
the United States Mail, first class postage prepaid, and addressed to each
holder of record at his or her address appearing on the books of the
Corporation. Any notice required by the provisions hereof to be given to the
Corporation shall be deemed given if deposited in the United States Mail, first
class postage prepaid, and addressed to the Corporation at 1100 Louisiana
Street, Suite 4400, Houston, Texas 77002, or such other address as the
Corporation shall provide in writing to the holders of Series B Preferred.

        13.    Amendments.    With the consent or approval of the holders of at
least a majority of the Series B Preferred then outstanding, the Corporation may
amend or modify any of the foregoing rights, privileges and preferences with
respect to the shares of Series B Preferred, provided that no such amendment may
materially and adversely affect a holder of Series B Preferred without the
holder's approval. Notwithstanding the foregoing, the Corporation may amend or
modify (i) the consent rights described in Section 8 of the holders of Series B
Preferred and (ii) any other rights described herein requiring consent or
approval of the holders of 662/3% of the Series B Preferred only with the
approval by the vote or written consent of the holders of at least two-thirds of
the Series B Preferred then outstanding.

[Signature Page Follows]

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        IN WITNESS WHEREOF, the undersigned has executed this Certificate as of
November 22, 2004.

    PETROHAWK ENERGY CORPORATION
 
 
By:
/s/  FLOYD C. WILSON      

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    Name: Floyd C. Wilson     Title: President & Chief Executive Officer

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QuickLinks

Exhibit 10.4

CERTIFICATE OF DESIGNATION, PREFERENCES, RIGHTS AND LIMITATIONS of SERIES B 8%
AUTOMATICALLY CONVERTIBLE PREFERRED STOCK of PETROHAWK ENERGY CORPORATION