***Exhibit 4.1*****QUICKSILVER RESOURCES INC.,****THE SUBSIDIARY GUARANTORS PARTIES HERETO****AND****JPMORGAN CHASE BANK, NATIONAL ASSOCIATION****as TRUSTEE** **THIRD SUPPLEMENTAL INDENTURE****Dated as of September 26, 2006**
 

 
          This THIRD SUPPLEMENTAL INDENTURE, dated as of September 26, 2006 (this “SupplementalIndenture”), among Quicksilver Resources Inc., a Delaware corporation (the “Company”), theSubsidiary Guarantors (as defined in the Indenture referred to herein) and JPMorgan Chase Bank,National Association, as Trustee.W I T N E S S E T H          WHEREAS, the Company and the Trustee entered into an Indenture (the “Original Indenture”),dated as of December 22, 2005, as supplemented by a First Supplemental Indenture, dated as of March16, 2006, among the Company, the Subsidiary Guarantors party thereto and the Trustee (the “FirstSupplemental Indenture”) and a Second Supplemental Indenture, dated as of July 31, 2006, among theCompany, the Subsidiary Guarantors party thereto and the Trustee (the “Second SupplementalIndenture” and, together with the Original Indenture and the First Supplemental Indenture, the“Indenture”), pursuant to which the Company has issued $350,000,000 of aggregate principal amountof71/8% Senior Subordinated Notes due 2016 (the “Notes”);          WHEREAS, Section 6.01(a) of the First Supplemental Indenture provides that Section 10.01 ofthe Original Indenture applies to the Notes;          WHEREAS, Section 10.01(h) of the Original Indenture provides that, without the consent of anyHolders, the Company, when authorized by a Board Resolution, and the Trustee may enter into one ormore indentures supplemental to the Indenture to cure any ambiguity, to correct or supplement anyprovision of the Indenture which may be defective or inconsistent with any other provision of theIndenture, or to make any other provisions with respect to matters or questions arising under theIndenture, provided that any action pursuant to Section 10.01(h) will not adversely affect theinterests of the Holders of Securities of any Series in any material respect; and          WHEREAS, the Board has approved an amendment to Section 3.11 of the First SupplementalIndenture to be effected pursuant to this Supplemental Indenture;          NOW THEREFORE, in consideration of the foregoing, the Company, the Subsidiary Guarantors andthe Trustee mutually covenant and agree for the equal and ratable benefit of the Holders of theNotes as follows:**ARTICLE 1**          Section 1.01. Effect. This Supplemental Indenture is supplemental to the Indentureand does and shall be deemed to form a part of, and shall be construed in connection with and aspart of, the Indenture for any and all purposes.          Section 1.02. Effective Time. This Supplemental Indenture shall become effectiveimmediately upon its execution and delivery by the Company, the Subsidiary Guarantors and theTrustee.**ARTICLE 2**          Section 2.01. Amendment. The fifth paragraph of Section 3.11 of the FirstSupplemental Indenture is hereby amended to read in its entirety as follows:     The Company may not permit any Subsidiary Guarantor to consolidate with ormerge with or into any Person (other than another Subsidiary Guarantor) and may notpermit the conveyance, transfer or lease of substantially all of the assets of anySubsidiary Guarantor (other than to another Subsidiary Guarantor) unless:     (1) (a) the Person formed by the consolidation or into which the SubsidiaryGuarantor merged or to which all or substantially all of the Subsidiary Guarantor’sproperties and assets are transferred is a corporation, partnership, limitedliability company, business trust, trust or other legal entity organized and validlyexisting under the laws of the United States, any state
 

 
thereof, or the District ofColumbia and such Person (if not such Subsidiary Guarantor) will expressly assume,by supplemental indenture, all the obligations of such Subsidiary Guarantor underits Subsidiary Guarantee; (b) immediately after the transaction and the Incurrenceor anticipated Incurrence of any Indebtedness to be Incurred in connectiontherewith, no Event of Default exists; and (c) the Company will deliver to theTrustee an Officers’ Certificate and an Opinion of Counsel, each to the effect thatthe conditions set forth above have been satisfied; or     (2) the transaction is made in compliance with Section 3.07 of this FirstSupplemental Indenture.**ARTICLE 3**          Section 3.01. Ratification of Indenture. Except as specifically modified herein, theIndenture and the Notes are in all respects ratified and confirmed (mutatis mutandis) and shallremain in full force and effect in accordance with their terms.          Section 3.02. Defined Terms. All capitalized terms used but not defined herein shallhave the same respective meanings ascribed to them in the Indenture.          Section 3.03. Trustee. Except as otherwise expressly provided herein, no duties,responsibilities or liabilities are assumed, or shall be construed to be assumed, by the Trustee byreason of this Supplemental Indenture. This Supplemental Indenture is executed and accepted by theTrustee subject to all of the terms and conditions set forth in the Indenture with the same forceand effect as if those terms and conditions were repeated at length herein and made applicable tothe Trustee with respect hereto.          Section 3.04. Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, ANDCONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.          Section 3.05. Counterparts. The parties may sign any number of copies of thisSupplemental Indenture. Each signed copy shall be an original, but all of them together representthe same agreement.          Section 3.06. Headings. The headings herein are inserted for convenience of referenceonly and are not intended to be part of, or to affect the meaning or interpretation of, thisSupplemental Indenture.          Section 3.07. Recitals by the Company. The recitals hereto are statements only of theCompany and shall not be considered statements of or attributable to the Trustee.
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     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to beduly executed as of the date first above written.      QUICKSILVER RESOURCES INC.