CONTRIBUTION, CONVEYANCE AND ASSUMPTION AGREEMENT

Exhibit 10.7

CONTRIBUTION, CONVEYANCE AND ASSUMPTION AGREEMENT

This Contribution and Assumption Agreement, dated as of December 18, 2006 (this “ Contribution Agreement ”), is by and among Atlas America, Inc., a Delaware corporation (“ Atlas America ”), Atlas Energy Resources, LLC, a Delaware limited liability company (“ Atlas Energy ”), and Atlas Energy Operating Company, LLC, a Delaware limited liability company (“ Energy Operating ”). The above-named entities are sometimes referred to in this Contribution Agreement each as a “ Party ” and collectively as the “ Parties .”

W I T N E S S E T H :

WHEREAS , Atlas America currently wholly owns the subsidiaries listed on Schedule 1 hereto (collectively, the “ Subsidiaries ”) and the assets described on Schedule 2 hereto (collectively, the “ Assets ”) representing Atlas America’s natural gas and oil exploration, development, operation, maintenance and production business (the “ Business ”);

WHEREAS , Atlas America has formed Atlas Energy pursuant to the Delaware LLC Act for the purpose of acquiring, owning and operating the Business;

WHEREAS , in order to accomplish the objectives and purposes in the preceding recital, the following actions have been taken prior to the date hereof (the “ Pre-Closing Actions ”):

1

WHEREAS , Atlas America and certain of the Subsidiaries are parties to the Gathering Agreement (as defined in Article I) and Atlas America has agreed to assume certain obligations of those Subsidiaries thereunder;

WHEREAS , concurrently with the consummation of the transactions contemplated hereby, each of the following shall occur:

NOW , THEREFORE , in consideration of the mutual covenants, representations, warranties and agreements herein contained, the parties hereto agree as follows:

ARTICLE I

DEFINITIONS

Section 1.1 Capitalized terms used herein and not otherwise defined shall have the meanings ascribed to them below:

“ APL ” means Atlas Pipeline Partners, L.P., a Delaware limited partnership.

2

“ Atlas America Entities ” means Atlas America and any Person controlled, directly or indirectly, by Atlas America, other than Atlas Energy, Energy Operating and any subsidiary of any such Person.

“ Atlas Energy Group ” means Atlas Energy, Energy Operating and any subsidiary of any such Person, treated as a single consolidated entity, and each Investment Program.

“ Atlas Energy Assets ” means the Transferred Assets and any assets and properties owned or leased by any member of the Atlas Energy Group.

“ Authority ” means (i) the United States of America, (ii) any state, province, county, municipality or other governmental subdivision within the United States of America, (iii) any court or any governmental department, commission, board, bureau, agency or other instrumentality of the United States of America, or of any state, province, county, municipality or other governmental subdivision within the United States of America and (iv) the National Association of Securities Dealers.

“ Business Day ” means any day other than a Saturday, a Sunday or any other day when banks are not open for business generally in the State of Delaware.

“ Closing ” means the closing of the transactions contemplated pursuant to this Contribution Agreement.

“ Closing Date ” means the date of Closing.

“ Delaware LLC Act ” means the Limited Liability Company Act of the State of Delaware, as amended and any successor to such act.

“ Gathering Agreement ” means the Master Natural Gas Gathering Agreement dated as of February 2, 2000 among Atlas America, Resource Energy, LLC (formerly Resource Energy, Inc.), Viking Resources, LLC (formerly Viking Resources Corporation) and APL, as amended from time to time.

“ Investment Program ” means a Person principally engaged in the drilling of natural gas and oil wells for which Atlas America or any of the Subsidiaries or any of their subsidiaries acts as a general partner, managing partner or manager and the securities of which have been offered and sold to investors.

“ Offering ” means the initial public offering of the Common Units contemplated by the Registration Statement.

“ Operating Agreement ” means the Amended and Restated Operating Agreement of Atlas Energy dated of even date herewith by and among Atlas America, Inc. and the members party thereto, as amended from time to time.

“ Person ” means an individual, corporation, partnership (limited or general), limited liability company, trust, joint stock company, unincorporated association or other legal entity.

3

“ Registration Statement ” means the registration statement on Form S-1 filed with the U.S. Securities and Exchange Commission by Atlas Energy (File No. 333-136094).

“ Toxic Tort ” means a claim or cause of action arising from personal injury or property damage incurred by the plaintiff that is alleged to have been caused by exposure to, or contamination by, Hazardous Substances that have been released into the environment by or as a result of the actions or omissions of the defendant.

“ Underwriters ” means those of the underwriting syndicate as referenced in the Underwriting Agreement between UBS Securities LLC, as representative of the Underwriters, and Atlas Energy, dated as of December 12, 2006.

ARTICLE II

CONTRIBUTION AND DISTRIBUTION TRANSACTIONS

Section 2.1 Contribution by Atlas America to Energy Operating .

(a) Contribution . Atlas America hereby grants, contributes, conveys, bargains, assigns, transfers, sets over and delivers to Energy Operating, its successors and assigns, for its and their own use forever, all right, title and interest of Atlas America in and to all of the Assets and all of the Equity Interests (together with the Assets, the “ Transferred Assets ”), subject to encumbrances that do not materially adversely affect the value of the Transferred Assets or the ability of the Atlas Energy Group to own and operate the Transferred Assets in substantially the same manner as they were operated immediately prior to the Closing Date, in exchange for (i) 30,301,746 Common Units, (ii) 748,456 Class A Units, (iii) the Management Incentive Interests and (iv) the right to receive $121,730,000, in part as a reimbursement of certain capital expenditures made with respect to the Transferred Assets.

TO HAVE AND TO HOLD all of such right, title and interest in the Transferred Assets unto Energy Operating, its successors and assigned, together with all and singular rights and appurtenances thereto in anywise belonging, subject, however, to the terms and conditions stated in this Contribution Agreement, and in such instruments of conveyance forever.

(b) Assumed Liabilities . Subject to Section 2.1(c), Energy Operating hereby irrevocably and absolutely assumes, agrees to perform, and when due, pay and discharge, only the obligations and liabilities relating to the Transferred Assets which accrue on or after the Closing Date and only to the extent such obligations and liabilities are not overdue or delinquent on the Closing Date without regard to any grace period and without the occurrence of any increase in amounts due (the “ Assumed Liabilities ”); provided , however , that said assumption and agreement to assume the Assumed Liabilities shall not (i) increase the obligation of Energy Operating with respect to the Assumed Liabilities beyond that of Atlas America, (ii) waive any valid defense that was available to Atlas America with respect to the Assumed Liabilities or (iii) enlarge any rights or remedies of any third party under any of the Assumed Liabilities.

4

(c) Prorations . All obligations and liabilities assumed by Energy Operating under this Contribution Agreement that relate to both periods of time prior to the Closing Date and periods of time from and after the Closing Date shall be prorated as of the close of business on the Closing Date, whether or not such adjustment would normally be made as of such time. It is the intention of the Parties that Energy Operating should operate the Business and the Transferred Assets for its own account from and after the Closing Date.

Section 2.2 Contribution by Atlas America to Atlas Management . Atlas America hereby grants, contributes, conveys, bargains, assigns, transfers, sets over and delivers to Atlas Management, its successors and assigns, for its and their own use forever, all right, title and interest of Atlas America in and to (i) 748,456 Class A Units and (ii) the Management Incentive Interests.

Section 2.3 General Provisions Relating to Assumption of Liabilities. Notwithstanding anything to the contrary contained in this Agreement including the terms and provisions of this Article II, none of the Parties shall be deemed to have assumed, and none of the Transferred Assets have been or are being contributed subject to, (a) any liens or security interests securing consensual indebtedness covering any of the Transferred Assets, except for encumbrances permitted by this Contribution Agreement, and all such liens and security interests shall be deemed to be excluded from the assumptions of liabilities made under this Article II or (b) any of the liabilities covered by the indemnities set forth in this Contribution Agreement to the extent such liabilities are covered by such indemnities, and all such liabilities shall be deemed to be excluded from the assumptions of liabilities made under this Article II to the extent that such liabilities are covered by such indemnities.

Section 2.4 Public Cash Contribution . The Parties acknowledge a capital contribution by the public through the Underwriters to Atlas Energy of $132,825,000 in cash ($123,530,413 after the Spread of $8,298,400 and the structuring fee of $996,187) in exchange for 6,325,000 Common Units.

Section 2.5 Specific Conveyances. To further evidence the contributions and conveyances of the Transferred Assets, each party making such contribution and conveyances may have executed and delivered to the party receiving such contribution certain conveyance, assignment and bill of sale instruments (the “ Specific Conveyances ”). The Specific Conveyances shall evidence and perfect such sale and contribution made by this Contribution Agreement and shall not constitute a second conveyance of any assets or interests therein and shall be subject to the terms of this Contribution Agreement.

Section 2.6 Payment of Transaction Expenses by Atlas Energy . The Parties acknowledge (a) the payment by Atlas Energy, in connection with the transactions contemplated hereby, of estimated transaction expenses in the amount of $1.8 million (exclusive of the Spread and the structuring fee) and (b) the distribution by Atlas Energy of $121,730,000 to Atlas America, in part as a reimbursement of certain capital expenditures incurred with respect to the Transferred Assets.

Section 2.7 Issuance of New Certificates . At the Closing, Atlas Energy shall issue to each of Atlas America and Atlas Management a certificate or certificates, which may be held in

5

book entry form, representing the number of Common Units and Class A Units to be issued to each of them pursuant to this Article II. Each such certificate shall be registered in the name of the Person or Persons specified by the recipient thereof to Atlas Energy in writing at least two Business Days prior to the Closing.

Section 2.8 Certificate Legends . The certificates evidencing the Common Units and Class A Units shall bear a legend substantially in the form set forth below and containing such other information as Atlas Energy may deem necessary or appropriate:

T HE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED , OR ANY STATE SECURITIES LAWS , AND NEITHER THE SECURITIES NOR ANY INTEREST THEREIN MAY BE OFFERED , SOLD , TRANSFERRED , PLEDGED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND SUCH LAWS OR PURSUANT TO AN EXEMPTION THEREFROM WHICH , IN THE OPINION OF COUNSEL FOR THE HOLDER , WHICH COUNSEL AND OPINION ARE REASONABLY SATISFACTORY TO COUNSEL FOR THIS COMPANY , IS AVAILABLE .

ARTICLE III

GATHERING AGREEMENT

Section 3.1 Assumption of Obligations by Atlas America . Atlas America hereby expressly assumes, for itself and its successors and assigns, the obligations of each of the Atlas Energy, Energy Operating and the Subsidiaries, as they may appear, to timely pay gathering fees to APL under Article 7 and 8 of the Gathering Agreement accruing from and after the Closing Date and agrees to keep, perform and observe all of the covenants and conditions contained therein on the part of any of them to be kept, performed and observed from and after the Closing Date. A

Section 3.2 Assignment by Atlas Energy . Each of Atlas Energy and Energy Operating, on their own behalf and on behalf of the Subsidiaries, hereby irrevocably assigns, sets over, transfers and conveys to Atlas America all of the right, title and interest of any of them in and to all of the gathering fees (i) accruing to any of them from the Investment Programs or (ii) attributable to the production interest of Atlas Energy, Energy Operating or any of the Subsidiaries for gas gathered from and after the Closing Date pursuant to the Gathering Agreement (the “ Assigned Amounts ”). Each of Atlas Energy and Energy Operating shall pay, and shall cause each of the Subsidiaries to pay, the Assigned Amounts to Atlas America within 15 Business Days after the end of the month in which received by them.

ARTICLE IV

ADDITIONAL TRANSACTIONS

Section 4.1 Over-Allotment Option . The Parties acknowledge that the Underwriters exercised their option to purchase additional Common Units (the “ Option ”) in whole and that the public, through the Underwriters, contributed additional cash of $19,923,750 in cash

6

($18,529,562 after the Spread of $1,244,760 and the structuring fee of $149,428) to Atlas Energy in exchange for an additional 948,750 Common Units.

Section 4.2 Redemption of Common Units by Atlas Energy . The Parties acknowledge that Atlas Energy will use the net proceeds from the issuance of the additional Common Units pursuant to the exercise of the Option to redeem 948,750 Common Units from Atlas America at a redemption price equal to the same net price received by Atlas Energy from the Underwriters.

ARTICLE V

REPRESENTATIONS AND WARRANTIES

Section 5.1 Representations and Warranties of Atlas America . Atlas America hereby represents and warrants to Atlas Energy and Energy Operating as follows as of the date of this Contribution Agreement:

(a) Status of Atlas America . Atlas America has been duly incorporated and is validly existing and in good standing under the laws of the State of Delaware, with all corporate power and authority necessary to own or hold its properties and conduct the businesses in which it is engaged and to execute and deliver this Contribution Agreement and to consummate the transactions contemplated hereby.

(b) Title to Subsidiaries . Atlas America owns 100% of the issued and outstanding equity interests in the Subsidiaries; the Subsidiaries own 100% of the issued and outstanding equity interests in their subsidiaries as set forth on Schedule 1 ; and all such equity interests have been duly authorized and validly issued in accordance with the charter documents of the relevant entity, and Atlas America and the Subsidiaries own their respective equity interests free and clear of all liens, claims, options, charges, encumbrances or restrictions of any kind. There are no outstanding warrants, options, agreements, convertible or exchangeable securities, phantom stock or other commitments pursuant to which any Subsidiary or any of their subsidiaries is or may become obligated to issue, sell, purchase, return or redeem any shares of capital stock or other securities and no equity securities of any Subsidiary or any of their subsidiaries are reserved for issuance for any purpose.

(c) Corporate Action/Enforceability . All corporate action required to be taken by Atlas America or any of its securityholders for the authorization, execution and delivery of this Contribution Agreement and the consummation of the transactions contemplated by this Contribution Agreement and the Pre-Closing Actions have been validly taken. This Contribution Agreement constitutes the valid and binding obligations of Atlas America, enforceable in accordance with its terms except as such enforceability may be limited by applicable bankruptcy or other similar laws affecting the rights and remedies of creditors generally as well as by general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law).

(d) Conflicts . None of the (i) the execution, delivery and performance of this Contribution Agreement by Atlas America, or (ii) consummation of the transactions

7

contemplated hereby and the Pre-Closing Actions by Atlas America (A) conflicts or will conflict with or constitutes or will constitute a violation of Atlas America’s or any member of the Atlas Energy Group’s certificate of incorporation, bylaws or other organizational documents, (B) conflicts or will conflict with or constitutes or will constitute a breach or violation of, or a default (or an event that, with notice or lapse of time or both, would constitute such a default) under, any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which Atlas America or any member of the Atlas Energy Group is a party or by which Atlas America’s or any member of the Atlas Energy Group’s properties may be bound, (C) violates or will violate any statute, law or regulation or any order, judgment, decree or injunction of any Authority having jurisdiction over Atlas America or any member of the Atlas Energy Group or any of their respective properties or assets, or (D) results or will result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of Atlas America or any member of the Atlas Energy Group, which conflicts, breaches, violations, defaults or liens, in the case of clauses (B) or (D), would, individually or in the aggregate, have a material adverse effect on (i) the transactions contemplated hereby or (ii) the ownership and use by Atlas Energy, Energy Operating and the Subsidiaries of the Atlas Energy Assets at or after the Closing Date (a “ Material Adverse Effect ”).

(e) Consents . No permit, consent, approval, authorization, order, registration, filing or qualification of or with any Authority having jurisdiction over Atlas America, any member of the Atlas Energy Group or any of their respective properties or by any other third party is required in connection with (i) the execution, delivery and performance of this Contribution Agreement by Atlas America, or (ii) the consummation by Atlas America of the transactions contemplated by this Contribution Agreement and the Pre-Closing Actions, except for such consents that have been obtained or as to which the lack thereof is not reasonably likely to have a Material Adverse Effect.

(f) Title to Property . Upon Closing, one or more members of Atlas Energy Group will have:

(i)(A) good and defensible title to the producing oil and gas property interests (including the wells and the working and net revenue interests attributable thereto) (the “ Wells ”) included in the Atlas America reserve report, dated March 31, 2006, included in Registration Statement (the “ Reserve Report ”), subject only to encumbrances that do not materially adversely affect the value of such oil and gas property interests or the ability of the Atlas Energy Group to operate such oil and gas property interests in substantially the same manner as they were operated immediately prior to the Closing Date and (B) good and defensible title to each oil and gas lease as to which proved undeveloped reserves were included in the Reserve Report (the “ Leases ”), subject only to encumbrances that do not materially adversely affect the value of any such Lease or, in the event that the Atlas Energy Group does not have good and defensible title to such