Exhibit 2.1

| |  | A true copy of original Filed for Record this the 30th day of Sept., 2003
File No. 323645
Core Book 436 Folio    
Diane Huff
Clerk of Court
Richland Parish, LA
| |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------

ASSIGNMENT, CONVEYANCE AND BILL OF SALE

STATE
OF LOUISIANA

PARISHES
OF RICHLAND, MADISON and FRANKLIN

KNOWN
ALL MEN BY THESE PRESENTS:

WHEREAS,DELTA EXPLORATION AND DEVELOPMENT COMPANY, INC., tax ID
#, and CAMARK PRODUCTION CO., tax ID #75-307742
(successors to MWP NORTH LOUISIANA, LLC, successor to McGowan Working Partners) have acquired certain oil and
gas leasehold and equipment
interests in and to the Delhi Field Unit by virtue of Assignments from MWT North Louisiana, L.L.C., filed June 23, 2000, recorded in Book 419, DR#310944, Records of Richland Parish, Louisiana,
out of Delhi Package I, LTD and Eland Energy, Inc., recorded in Book 318, File No. 280940, dated April 15, 1996, Deed Records of Franklin Parish, Louisiana; Munoco Company, L.C., recorded in
Book 402, File No. 297789, dated February 14, 1997, Deed Records of Richland Parish, Louisiana; Murphy Exploration and Production Company recorded in Book 164, File 92951, dated January
28, 1997, Deed Records of Madison Parish, Louisiana; Richland Oil Company recorded in Book 170, File No. 94740, dated October 23, 1997, Deed Records of Madison Parish, Louisiana, and mense assignments
in and to the Delhi Field Unit, located in Madison, Richland, and Franklin Parishes, Louisiana.

NOW,
THEREFORE, DELTA EXPLORATION AND DEVELOPMENT COMPANY, INC., whose address is 105 East Shore Drive, Monroe, Louisiana 71201, and CAMARK PRODUCTION CO., P.O. Box B, Camden, Arkansas
71711-0120, hereinafter collectively referred to as "Assignors", for and in consideration of the sum of Ten Dollars ($10.00) and other valuable considerations paid, receipt of which is hereby
acknowledged, does hereby grand, sell, convey, assign and transfer untoNGS Sub. Corp.Tax ID #80-0076903, a foreign corporation domiciled in the State
of Delaware, whose principal business address is 3 Raydon Lane, Houston, Texas 77024, represented herein by its duly authorized President, Robert Herlin, hereinafter said corporation referred to as
"Assignee", EIGHTY (80.0%) PERCENT NET REVENUE INTEREST, representing ONE-HUNDRED (100.0%) PERCENT WORKING INTEREST, of Assignors' leasehold interests and ONE-HUNDRED (100%) of the equipment interests
along with all applicable contracts, rights of ways, burdens, reservations, exceptions and obligations within the geographical confines of the Delhi Field Unit, said unit boundaries being more
accurately described in that certain Unitization Agreement dated August 5, 1952, recorded in Book 81, File No. 129, Deed Records, Franklin Parish, Louisiana, and all subsequent amendments,
subject to the following and subject to the terms and conditions specified and outlined on Exhibit "A" attached hereto and made a part hereof, including but not limited to the following, it
specifically excluding the retained assets described on Exhibit "A":



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For
the same consideration as first hereinafter recited, the Assignor does hereby bargain, grant, sell, convey and transfer unto Assignee the above-mentioned percentage of Assignor's
rights, title and interest in and to the wells located on the lands, together with that same percentage of all material, equipment, easements and properties of any kind located therein and thereon and
used solely in connection therewith.

Assignee
acknowledges and represents that prior to accepting this Agreement, Conveyance and Bill of Sale, it conducted such inspection of the properties as it deemed reasonably prudent,
made itself familiar with the operations previously conducted thereon and satisfied itself as to the risks and obligations assumed hereunder.

Assignee
agrees to comply with all laws and with all rules, regulations and orders of all municipal, state and federal agencies and regulatory bodies in the conduct of all operations by
Assignee in and on, the lands covered hereby, including, but not by way of limitation, the proper plugging of any well(s) on the said lands, the proper disposal or treatment of wastes and the transfer
or assumption of applicable permits, bonds, approvals and licenses.

Subject
to the provisions of the following paragraphs, the following shall govern the rights and obligations of the parties hereto:



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Assignee
acknowledges that it has had the opportunity to inspect the Properties and test it as Assignee deems fit, and that the Properties and any personality, materials or fixtures
thereon are purchased WHERE IS, AS IS. Assignee exclusively waives any claims against Assignor for indemnity or contribution which it may have under civil law, common law or statute arising from or
relating to the condition of the Properties, including, without limitation, claims resulting from environmental damage or pollution and the existence of Naturally Occurring Radioactive Material (NORM)
on the Properties, fixtures and equipment which are the subject of this Agreement, together with any related fines, penalties and cleanup expenses, whether incident for such claim occurred prior to or
after the Effective Date.

It
is expressly understood by the parties hereto that Assignors do not make any representations or warranties, express or implied, as the condition and state of repair of the Properties,
its value, quality, merchantability, suitability or fitness for any uses or purposes, nor as to the current volume, nature, quality, classification, or value of the oil, gas or other mineral reserves
thereunder or covered thereby, nor with respect to any appurtenances thereto belonging or in any way appertaining to said Properties or otherwise. Assignors have advised Assignee and Assignee has
acknowledged that certain spills of oil and chemicals from oil and gas exploration, development, or production (regulated or under the jurisdiction of the applicable commission, department or other
governmental authority of the State of Louisiana) have occurred, or may have occurred, upon the property, which could have resulted in contamination of the soil, water, ground water or improvements on
the Properties; however, Assignors know of no other wastes or other contaminants upon the Property which Assignee cannot discover by prudent examination and inspection of the Properties, nor of any
violation of any federal or state laws, rules or regulations, concerning environmental acts or hazards. Furthermore, Assignors have cautioned Assignee to thoroughly examine and inspect the Properties
for any such conditions or violations and generally as to the condition of the Properties and its improvements, and Assignee hereby acknowledges such obligations and assumes all liabilities associated
therewith to the extent of Assignee's working interest ownership percentage.

Furthermore,
Assignee certifies that said Property (including, but not limited to, any oil, gas or other mineral reserves underlying said Property) has been carefully inspected by
Assignee, that Assignee is familiar with its condition and value thereof, and the improvements and appurtenances (including electric wiring and machinery installed thereon) located on the Property,
inclusive of any hydrocarbons, other soil contaminants or waste substances, whether similar or dissimilar, that may be present in the soil, water and groundwater, that Assignee has engaged such
contractors or consultants as Assignee deems prudent for tests and surveys of the soil, water, groundwater, Wells and Equipment, and improvements on the Property, and that Assignee assumes any and all
obligations, risks and liabilities associated therewith to the extent of Assignee's working interest ownership. Assignee acknowledges that the Property has been or may have been used in connection
with oil, gas and other mineral exploration, development and operations, as well as with respect to processing and refining operations, and, as such, equipment, appurtenances, processing and other
facilities, plants, buildings, structures, improvements, abandoned and other tanks and piping (including above ground and underground tanks and piping), storage facilities, gathering and distribution
lines, wells and other

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petroleum
production facilities and appurtenances which have not been excepted and excluded from this conveyance may be located thereon. Assignee further accepts said Property (including, but not
limited to, any oil, gas or other minerals and/or mineral reserves underlying said Property) AS IS, WHERE IS, IN ITS PRESENT CONDITION AND STATE OF REPAIR AND WITHOUT ANY REPRESENTATIONS, GUARANTIES,
OR WARRANTIES, EXPRESS OR IMPLIED, AS TO ITS TITLE, VALUE, QUALITY, MERCHANTABILITY, OR ITS SUITABILITY OR FITNESS FOR ASSIGNEE'S INTENDED USE, OR FOR ANY USES OR PURPOSES WHATSOEVER, OR THAT SAID
PROPERTY HAS BEEN RENDERED FREE FROM ANY DEFECTS, HAZARDS OR DANGEROUS CONDITIONS.

Indemnification

Notwithstanding any other terms in this assignment to the contrary, assignors shall indemnify assignee for any environmental damages arising out of operation of
the properties only during or from the period of time that the properties were operated by Arkla Petroleum, LLC, beginning with Arkla Petroleum, LLC's operations in 2002, through today's date.

This
agreement and any disputes arising out of it will be governed by the Laws of the State of Louisiana.

Without
limiting the generality of the foregoing but in furtherance of same, Assignee accepts the Properties in its "as is, where is" condition. Assignors disclaim any and all liability
arising in connection with any environmental matters, including, without limitation, any presence of Naturally Occurring Radioactive Material (NORM) on the Property. In addition, there are no
warranties or representations, express or implied, as to the accuracy or completeness of any data, information or materials heretofore or hereafter furnished in connection with the Properties as to
the quality or quantity of the hydrocarbon and any other mineral reserves, if any, attributable to the interest conveyed herein or the ability of the Property to produce hydrocarbons or any other
minerals, and any and all data, information and material furnished by Assignor is provided as a convenience only and any reliance on or use of the same is at Assignee's sole risk.

Other
than as set out above in the indemnification clause for the operation period of Arkla Petroleum, LLC, Assignee hereby waives and releases Assignors of and from any claims, actions,
causes of action, demands, rights, damages, costs, expenses or compensation whatsoever, direct or indirect, known or unknown, foreseen or unforeseen, which Assignee now has or which may arise in the
future on account of or in any way growing out of or connected with the physical or environmental condition of the property or any law or regulation applicable to it, including, but not limited to the
Comprehensive Environmental Response, Compensation and Liability Act, 42 U.S.C. Section 9601et seqor similar state statutes, whether such claim,
action, etc. arose from events occurring before or after effective date of this conveyance, except as to the extent of Assignor's retained working interest.

This
Assignment, Conveyance and Bill of Sale supercedes the provisions and conditions contained in that certain Letter Agreement with Assignors dated August 25, 2003.

Assignors
reserve the right to have access, and at Assignor's expense, the right to copy, excerpt from, or reproduce any records to the extent necessary for:



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The
reservation herein made and the provisions and covenants contained herein shall attach to and run with the leases assigned and the lands herein described or referred to and shall be
binding upon and inure to the benefit of Assignors and Assignee and their respective heirs, administrators, executors, devisees, trustees, successors and assigns.

This
Assignment, Conveyance and Bill of Sale shall be effective for all purposes as of the 26 day of September, 2003 at 7:00 P.M., Central Standard Time.

TO
HAVE AND TO HOLD the same unto the said Assignee, its successors and assigns according to the terms and conditions of the Oil and Gas Leases, the said Assignee to perform all of the
conditions, obligations, and covenants thereof and the terms hereof.

THIS
ASSIGNMENT, CONVEYANCE AND BILL OF SALE IS MADE WITHOUT WARRANTY TO TITLE OF ANY KIND, EXPRESS OR IMPLIED, AS TO ALL WELLS, MATERIALS AND EQUIPMENT COVERED HEREBY, THIS ASSIGNMENT,
CONVEYANCE AND BILL OF SALE IS MADE WITHOUT WARRANTY, EXPRESS OR IMPLIED, AS TO MERCHANTABILITY AND FITNESS FOR PARTICULAR PURPOSE, AND ASSIGNEE ACCEPTS SUCH WELLS, MATERIALS AND EQUIPMENT "AS IS".

NGS
Sub. Corp. (Assignee) agrees to provide within 120 days of the effective dateat Assignee's expensea performance surety bond or Bank Letter of Credit
approved by Assignor, in favor of Assignors in the amount of $301,835.00 to secure the obligations of Assignee under this Assignment, Conveyance and Bill of Sale, includingbut not limited
toplugging, clean up and other environmental obligations under this Assignment, the subject leases, State and Federal regulations and any applicable law.

Assignee
agrees that it will provide to Assignors evidence of annual renewal of said letter of credit or bond 30 days prior to the expiration thereof so long as said obligations
continue. Failure to do so shall constitute default under this agreement and under the Mortgage between the parties of this same date. Approval of the Bond or Bank Letter of Credit by Assignors shall
not be unreasonably withheld; however, if it is withheld, Assignors shall notify Assignee of the reason for the disapproval and Assignee shall have the opportunity and a reasonable time to correct the
situation before being in default under this agreement and under the mortgage between the parties.

Assignors
agree to reduce amount of said bond required at the annual renewal dates in the amount of $5,000.00 for each well location which Assignee plugs and abandons and restores to the
satisfaction of Assignors. A reduction in an agreed amount shall be allowed for clean up work performed on part or all of the Station #4 Saltwater Disposal Facility and the LACT Facility #3. Assignee
agrees to provide documentation that the wells and/or facilities have been plugged/restored in accordance with landowner and lease requirements, and State and Federal requirements.

Venue
for any disputes arising out of this assignment shall be Richland Parish, Louisiana.

Ad
Valorem taxes will be prorated as of the effective date of this sale.

IN
WITNESS WHEREOF, the said DELTA EXPLORATION AND DEVELOPMENT COMPANY, INC., and CAMARK PRODUCTION CO., as Assignors, and NGS SUB. CORP., as Assignee, have caused their names to be
affixed to this, in triplicate originals, as of this 25th day of September, 2003.

WITNESSES:

|/s/ [ILLEGIBLE] |  | DELTA EXPLORATION AND DEVELOPMENT COMPANY, INC.
|--------------- |  | -----------------------------------------------
|/s/ [ILLEGIBLE] |  | By:                                            

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STATE
OF LOUISIANA
PARISH OF OUACHITA

THIS
DAY personally appeared before me, the undersigned authority in and for said Parish and State, the within named James H. Jones, President of Delta Exploration and Development
Company, Inc., a Louisiana Domestic Corporation, who acknowledged that he signed and delivered the within and foregoing instrument on the day and year therein mentioned, as the act and deed of said
Corporation, being first thereunto duly authorized so to do.

| |  | /s/ [ILLEGIBLE]NOTARY PUBLIC |  | 
| |  | ---------------------------- |  | 

|/s/ [ILLEGIBLE] |  | CAMARK PRODUCTION CO.
|--------------- |  | ---------------------
|/s/ [ILLEGIBLE] |  | By:                  

STATE
OF LOUISIANA
PARISH OF OUACHITA

THIS
DAY personally appeared before me, the undersigned authority in and for said Parish and State, the within named H.M. Berg, Jr., President of Camark Production Co., a Foreign
Corporation, who acknowledged that he signed and delivered the within and foregoing instrument on the day and year therein mentioned, as the act and deed of said Corporation, being first thereunto
duly authorized so to do.

| |  | /s/ [ILLEGIBLE]NOTARY PUBLIC |  | 
| |  | ---------------------------- |  | 

|/s/ [ILLEGIBLE] |  | NGS SUB. CORP.
|--------------- |  | --------------
|/s/ [ILLEGIBLE] |  | By:           

STATE
OF LOUISIANA
PARISH OF OUACHITA

THIS
DAY personally appeared before me, the undersigned authority in and for said Parish and State, the within named Robert Herlin, President of NGS Sub Corp., a Foreign Corporation, who
acknowledged that he signed and delivered the within and foregoing instrument on the day and year therein mentioned, as the act and deed of said Corporation, being first thereunto duly authorized so
to do.

| |  | /s/ [ILLEGIBLE]NOTARY PUBLIC |  | 
| |  | ---------------------------- |  | 

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EXHIBIT "A"

Attached
hereto and made a part hereof that certain Assignment, Conveyance and Bill of Sale, and Mortgage, by and between Delta Exploration and Development Company, Inc., Camark
Production Co., and NGS Sub. Corp., effective September 25, 2003.

Delta
Exploration and Development Company, Inc. and Camark Production Co. convey 100.0% of itsworking interestleasehold rights and well
bores and equipment in the Delhi Field, with James H. Jones, Individually, retaining this 4.86% overriding royalty interest, carried free and clear of any production costs; and the conveyance to NGS
Sub. Corp. is less and except the following:



WELLS
NOT CONVEYED, TO BE OPERATED BYMCGOWAN WORKING PARTNERS OR OTHERS:
Holt Bryant Producers:
164-2
177-2
195-2
177-4(TA)

Mengel
Well bores:

|Producers |  | SWD    |  | TA     |  | Others
|--------- |  | ------ |  | ------ |  | ------
|175-39    |  | 182-1  |  | 187-16 |  | 177-1 
|182-2     |  | 188-14 |  | 188-12 |  | 170-1 
|196-2     |  | 189-2  |  | 201-19 |  |       
|203-3     |  | 195-1  |  | 202-3  |  |       
|209-2     |  | 230-23 |  |        |  |       
|215-5     |  | 231-5  |  |        |  |       
|222-18    |  |        |  |        |  |       
|223-2     |  |        |  |        |  |       

WELLS ASSIGNED TO NGS SUB. CORP. AND NOT EXCEPTED:

|87-2   |  |      |  | 189-1 |  | 204-2 
|------ |  | ----- |  | ----- |  | ------
|102-5  |  | 178-1 |  | 190-1 |  | 208-1 
|102-7  |  | 178-2 |  | 191-1 |  | 209-1 
|154-1  |  | 179-1 |  | 196-1 |  | 210-1 
|158-3  |  | 179-2 |  | 196-3 |  | 210-2 
|161-36 |  | 180-1 |  | 197-1 |  | 215-1 
|166-1  |  | 181-2 |  | 197-2 |  | 215-17
|167-1  |  | 183-1 |  | 198-1 |  | 216-8 
|168-1  |  | 183-3 |  | 199-2 |  | 225-1 
|170-2  |  | 184-1 |  | 203-1 |  |       
|176-1  |  | 184-2 |  | 203-2 |  |       
|176-2  |  | 184-5 |  | 204-1 |  |       

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