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                                                                   EXHIBIT 10.19

ECOPETROL

CONTRACT NO.  GCI - 001 - 00

SELLER:       ARGOSY ENERGY INTERNATIONAL

PURPOSE:      PURCHASE AND SALES OF THE SANTANA CRUDE OIL

TERM:         JANUARY 1/ST/, 2000 TO DECEMBER 31/ST/, 2000

VALUE:        UNDETERMINED AMOUNT

The Contracting Parties on one hand, EMPRESA COLOMBIANA DE PETROLEOS -
ECOPETROL, hereinafter referred to as ECOPETROL, a Government-owned Industrial
and Commercial Corporation, authorized by Law 165 of 1948, and ruled by the by-
laws set forth by Decree 1209 of 1994, with its main office in Santafe de
Bogota, D.C., represented by DARIO FERNANDO LOPEZ MARTINEZ, of legal age, bearer
of citizenship card No. 19.076.354 issued in Bogota, resident in Bogota, who
hereby states: A. That he acts in his capacity as International Trade and Gas
Vice President (in charge) and according to the legal standards and internal
provisions of ECOPETROL; and B. On the other hand ARGOSY ENERGY INTERNATIONAL, a
corporation duly organized under the laws of the State of Utah, United States of
America, with its main place of business in Salt Lake City, Utah and a Colombian
branch incorporated by Public Deed No. 5323 of October 25/th/, 1983 and
registered at the Chamber of Commerce of Bogota under Registry No. 200848 of
November 23/rd/, 1983, represented by ALVARO JOSE CAMACHO R., of legal age,
bearer of citizenship card No. 79.142.747 of Bogota, hereinafter referred to as
SELLER, enter into a Purchase and Sale Contract of the Santana Crude Oil, ruled
by the following clauses:

CLAUSE ONE: PURPOSE AND AMOUNTS: SELLER agrees to sell and deliver to ECOPETROL,
under conditions set forth hereunder, the crude oil produced under the Santana
Shares Risk Contract, corresponding to SELLER, with the quality set forth in
Clause Two hereunder and ECOPETROL agrees to receive and pay for this crude oil.

PARAGRAPH 1: The Santana Shared Risk Contract was entered into on May 27/th/,
1987 with affective date May 27/th/,1987 among ECOPETROL, ARGOSY ENERGY
INTERNATIONAL AND NEO ENERGY INC. It was amended by Public Deed No. 00064 dated
January 19/th/, 1999, filed at Notary Public's Office 50 of Santafe de Bogota.

PARAGRAPH 2: All purchase shall be made by ECOPETROL, under the preliminary
crude oil purchase schedule agreed by the parties for six (6) months, which
ECOPETROL can modify upon written notice to SELLER given at least thirty (30)
days in advance.

CLAUSE TWO: QUALITY. The quality of the crude oil under this contract shall
include the following specifications: A) The crude oil gravity shall be that
with which such crude oil is obtained within production operations. B)  The
crude oil  water and sediment contents cannot exceed 0.5% in volume and their
determination shall be made through the methods ASTM-D4377 "Karl Fisher Method",
last revision and ASTM-D473 method "Sediment in Crude Oil and Fuel Oil
Extraction", last revision. C) Crude oil sulfur contents shall be that with
which such crude oil is obtained, within production operations: sulfur
determination

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shall be made through the ASTM-D2622 method, last revision "X Ray Sulfur
Analysis". D) Salt contents cannot exceed 20 pounds per 1.000 barrels of crude
oil and it shall be determined through AST-D3230 method "Salts in Crude Oil
(Electrometric Method)", last revision. When any of the preceding parameters or
specifications is not met or is not within the required parameters, ECOPETROL
has the right to reject such crude oil. However, if ECOPETROL should decide to
accept crude oil with a higher salinity level, the crude oil price shall be
penalized according to the following table:

                Salt Contents in             Penalty in US    To be covered by
           Pounds per Thousand Barrels       Dollars/Barrel
            20.1                 30.0           0.160             SELLER
            30.1                 40.0           0.180             SELLER
            40.1                 60.0           0.200             SELLER
            60.1                 80.0           0.220             SELLER
            80.1                100.0           0.240             SELLER

It is understood that SELLER shall do its best to deliver the contracted crude
oil, with a salt contents of less than twenty (20) pounds per thousand (1000)
barrels of crude oil. E. Any change concerning the aforementioned quality
specifications accepted by both parties must be recorded in a minutes signed by
the representatives of ECOPETROL and SELLER.

CLAUSE THREE: PLACE OF DELIVERY AND OWNERSHIP. The Crude Oil hereunder, shall be
transported by SELLER to the Santana Terminal, where it shall be measured and
analyzed. Later, from the outlet to the pipeline of the Santana Terminal it
shall be transported by ECOPETROL to the Tumaco Terminal. Delivery, ownership
and risk shall be conveyed from SELLER to ECOPETROL when crude oil passes the
outlet flange of the measurement system located at the Santana Terminal.
PARAGRAPH 1: Should the SANTANA ASSOCIATION build the Santana-Orito Pipeline,
measurement and conveyance of ownership shall be effective in Orito. In
addition, as of that date purchase and sale value shall be amended, since
transport rate from Santana to Orito shall be disregarded, pursuant to
Resolution 6031 of May 8/th/, 1998 of the Ministry of Mines and Energy.
PARAGRAPH 2: The Reception Capacity of the Santana Crude shall be limited to the
existing capacity of the Santana-Orito Pipeline.

CLAUSE FOUR: TERM. The initial term of this Agreement shall be twelve months
from January 1/st/, 2000 to December 31/st/, 2000 and can be extended by mutual
consent of the parties, prior to its expiration. Any extension shall be made in
writing.

CLAUSE FIVE: PRICE. The price which ECOPETROL will pay to SELLER for the crude
oil delivered at the Santana Terminal, is defined as follows: Price = Base Price
plus or less quality adjustment, less transport, less transport tax, less
marketing value.  PARAGRAPH 1: Base Price shall be the weighted average of the
export loads invoiced by ECOPETROL during that month.  PARAGRAPH 2:  Quality
adjustment applied hereunder shall be for API Gravity and Sulfur contents and
shall be estimated on a monthly basis according to the procedure described in
Attachment No. 1. PARAGRAPH 3: For estimation purposes of the transport variable
and of the transport tax, the basis to apply the rate set forth by the Ministry
of Mines and Energy shall be the number of gross barrels transported. The
Pipeline Transport Rules shall be considered part to this Contract once approved
by the

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parties and after being subject to the official approvals which could be
required. PARAGRAPH 4: The Santana - Tumaco transport cost, as well as the
respective transport tax shall be subject to any change made in this connection
during contract term. Santana - Tumaco transport rate corresponds to the rate
set forth in Resolution number 6031 of May 8/th/, 1998 of the Ministry of Mines
and Energy. Transport tax shall be 2% (two per cent) of the rate, pursuant to
Article 17 of Decree 2140 of 1955 adopted permanently by Law 10, 1961. These
rates shall be readjusted on a yearly basis pursuant to the aforementioned
Resolution No. 6031. PARAGRAPH 5: The Marketing cost shall be of 0.165 USD/BL.
PARAGRAPH 6: If during one month or several consecutive months (Month M) there
is no crude export, price shall be the price of the previous month (Month M-1).
This price shall be adjusted on the following month  (Month M+1) according to
the new price estimated in crude quotations of such month M+1. Taking the
Santana crude oil volume received on month M, the quality adjustment shall be
estimated with the average of  crude oil quotations in the market corresponding
of the three previous months to the month being adjusted (month M). PARAGRAPH 7:
In case of coastwise shipping of Tumaco's oil (South Blend) to the Refinery of
Cartagena, sale and price ECOPETROL will pay to SELLER shall be the same
obtained by the International Trade Management for the South Blend of Tumaco
(FOB Tumaco) received by the Refinery of Cartagena as a result of a bid plus or
less the quality adjustment, less the Santana - Tumaco transport cost and the
respective tax, less marketing (USD 0.165 per barrel). In case the Cartagena
Refinery purchases South Blend Crude Oil without a bid, the parties shall agree
on the mechanism to be used to estimate the crude oil's price. PARAGRAPH 8:
Notwithstanding the provisions set forth in Paragraph 2 concerning the quality
adjustment procedure, the parties can agree on a review of the crude oil market
and of the present method, and for this purpose they can resort to a mutual
consent on the crude oils to eliminate or add to the present market. In
addition, the parties can also hire an external consultant to determine whether
they should continue with the present method or should they use a new method. In
case parties do not reach an agreement in this connection, the present method
will continue to be applied. If it is necessary to apply a new method, it shall
be effective as of the deliveries made during the month when the agreement was
reached.

CLAUSE SIX: INVOICING AND FORM OF PAYMENT: SELLER shall invoice to ECOPETROL in
its Bogota Office, within the first 10 days of each month, the crude oil
delivered to ECOPETROL during the previous month after deducting the value
corresponding to royalties, contributions, and participations. Within 7 days of
the aforementioned term, ECOPETROL shall give SELLER the information it may
require to make the corresponding invoicing. Payment shall be made on a monthly
basis 30 days after receipt of invoice by ECOPETROL, after making the lawful
withholdings, if any. SELLER will inform ECOPETROL in writing at the time of
submission of the invoices about the percentages to apply on the net deliveries
of SELLER in order to determine the value to be paid in pesos and the value to
be paid in dollars. The percentages which can be applied on net deliveries are:
25% in pesos and 75% in dollars or 50% in pesos and 50% in dollars or 75% in
pesos and 25% in dollars. Invoicing shall be made based on the net volume, free
of water and sediment, adjusted at 60(degrees) F. For the portion in Colombian
pesos the market's representative exchange rate shall be used according to
certification by the Banking Superintendency, estimated as the arithmetic
average corresponding to the month when deliveries were made. PARAGRAPH 1: In
Case of delay in payment of the dollars portion on invoices not timely rejected
by ECOPETROL, ECOPETROL shall pay to SELLER as interest in dollars, the "Libor"
interest rate during the days of delay plus 1.0%.

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In case of delay in payment of the pesos portion, ECOPETROL shall pay the
maximum monthly interest rate certified by the Banking Superintendency. Invoices
collecting interests in pesos or dollars shall be paid within the ten (10) days
following receipt by ECOPETROL. PARAGRAPH 2: If ECOPETROL should not have United
States of America dollars available or should it be unable to get them from the
Colombian government or its authorized agencies, in order to cover the crude oil
purchases hereunder, it shall give notice, as soon as possible, and in writing
to SELLER, without prejudice as to the conditions set forth in paragraph 1
above, and the parities shall have a maximum 30 calendar days term as of such
notice of ECOPETROL, to reach a mutual agreement and an adequate solution.
PARAGRAPH 3: ECOPETROL shall have a 15 working days term to check, correct or
reject invoices filed by SELLER. Invoices not rejected within this term shall be
deemed final and correct. Any adjustment or correction required shall change the
valid date of the invoice to the date when the adjustment or correction is made
effective before ECOPETROL. ECOPETROL shall inform SELLER within the term set
forth about any rejected invoice in order for it to be adjusted and corrected,
clearly specifying the items which need to be adjusted or corrected and the
reason for such objection or correction.

CLAUSE SEVEN: INSPECTION AND MEASUREMENT. For the purpose of Clause Two, quality
will be determined pursuant to operational procedures set forth by common
consent between the parties in writing. Costs of these procedures shall be
shared by the parties at a pro rate of their ownership of the crude oil. In
addition to these operational procedures, any of the parties can appoint when so
desired an Independent Inspector to certify the amount and quality, to measure
the capacity of the tanks and to gauge volume measurement instruments. In this
latter case, the party requesting measurement shall bear with costs.

CLAUSE EIGHT: TERMINATION: Either SELLER or ECOPETROL can terminate this
purchase and sale contract by a written notice given 60 days in advance. If
SELLER decides to export directly its Santana crude oil, it shall give notice in
this connection to ECOPETROL 60 days in advance, and within this term ECOPETROL
and SELLER can terminate this contract.

CLAUSE NINE: DESTINATION: ECOPETROL can do as it pleases with the purchased
crude oil, provided that such destination is approved by applicable legal
provisions at this time.

CLAUSE TEN: ASSIGNMENT. Neither party can assign, sell or transfer all or part
of its rights and obligations hereunder to any third party without the prior and
written consent of the other party.

CLAUSE ELEVEN: FORCE MAJEURE. Neither ECOPETROL nor SELLER shall be liable for
the failure to comply with all or each of their obligations hereunder, if such
failure is due to force majeure or acts of God duly verified. Force majeure or
acts of God are those events which cannot be prevented and cannot be imputed to
the obliged party and which cannot be blamed upon that party and which place
such party in an absolute impossibility to meet its obligations such as: natural
phenomena (earthquakes, floods, land slides) or public order events (strike,
mutiny, terrorism, sabotage, breakage of the pipeline). Force majeure will not
relieve ECOPETROL from its obligation to pay SELLER those invoices

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filed for the sale of crude oil delivered by SELLER pursuant to the terms of
Clause Three hereunder.

CLAUSE TWELVE: APPLICATION OF COLOMBIA LAW. For all purposes hereunder, the
parties hereby appoint as contract domicile the city of Santafe de Bogota D.C.,
Republic of Colombia.  This contract shall be ruled by the Colombian law and the
parties shall be subject to the jurisdiction of Colombian courts and waive to
attempt any diplomatic claim concerning all aspects related to rights and
obligations arising hereunder, except for cases of denial of justice. For all
purposes hereunder, provisions of Article 25 of Law 40 of 1993 and of Chapter
Two, Title Three of Law 104 of 1993 and any additional or amending provision
shall be deemed to be part of this contract.

CLAUSE THIRTEEN: DISAGREEMENTS. A) Disagreements between the parties on legal
aspects regarding interpretation and execution of the contract which cannot be
amicably settled shall be put to the consideration and decision of the judicial
branch of Colombia. B) All factual or technical differences arising between the
parties which cannot be amicably settled, shall be submitted to the final
decision of experts appointed as follows:  one by each party and a third one
appointed by common consent of the two main experts appointed by the parties. If
the two experts appointed are unable to reach an agreement concerning the
appointment of the third expert, this person shall be appointed, upon request of
any of the parties, by the Board of Directors of the Colombian Engineers
Association, with its office in Santafe de Bogota D.C. Any accounting difference
which may arise between the parties regarding the interpretation and execution
of the contract and which cannot be amicably settled shall be submitted to the
decision of experts who must be public accountants appointed as follows: one by
each party and a third one appointed by common consent of the two main experts
appointed by the parties. If the two experts appointed are unable to reach an
agreement concerning the appointment of the third expert, this person shall be
appointed, upon request of any of the parties, by the Central Board of
Accountants of Bogota, and if it does not exist, by the Colombian Engineers
Association.  D) Both parties hereby declare that the decision of the experts
shall have all settlement effects and be final and binding. E) In case of a
disagreement between the parties on the technical, accounting and/or legal
qualification of the difference, its shall be deemed legal and item A) hereunder
shall apply. All aspects agreed in this Clause shall apply without prejudice, as
to the special procedures set forth hereunder.

CLAUSE FOURTEEN: TAXES AND EXPENSES. All taxes and expenses arising from the
signature and execution of this contract and its extensions or amendments shall
be exclusively covered by SELLER.

CLAUSE FIFTEEN: ADMINISTRATION CLAUSE. Administration of the contract shall be
carried out by the International Trade Management.

CLAUSE SIXTEEN: NOTICES. All notices hereunder shall refer to this clause and to
the pertinent clause. Notices shall be sent by certified mail, fax or delivered
to the addresses stated ahead and shall be deemed received at the respective
address on the date indicated at the receipt seal or on the date when the fax is
sent: EMPRESA COLOMBIANA DE PETROLEOS - ECOPETROL Calle 37 No. 7 - 43, Fax No.
3382585 and 3382583, Attention: International Trade and Gas Vice Presidency.
SELLER: ARGOSY ENERGY INTERNATIONAL. Diagonal 108 No. 7-54. Fax No. 6192098,
Santafe de Bogota D.C., Att:

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Alvaro Jose Camacho R., President. Any address change must be notified in
writing in advance.

In witness whereof this contract is signed in Santafe de Bogota, D.C., on
January 3/rd/, 2000 in Ecopetrol's Paper.


EMPRESA COLOMBIANA DE PETROLEOS
Signed: /s/ DARIO FERNANDO LOPEZ MARTINEZ
Vice President (in Charge)
International Trade and Gas

ARGOSY ENERGY INTERNATIONAL
Signed: /s/ ALVARO JOSE CAMACHO R.
Legal Representative

Seal: Ecopetrol
Reviewed
R 99761

This is a fair and accurate English translation of the original document which
is in the Colombian language.

                                 /s/ James L. Busby
                                 ------------------
                                 James L. Busby
                                 Secretary and Treasurer
                                 of Aviva Petroleum Inc.

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