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                                                                    EXHIBIT 10.1

ECOPETROL

CONTRACT NO.   GCI - 001 - 01

SELLER:        ARGOSY ENERGY INTERNATIONAL

PURPOSE:       PURCHASE AND SALES OF THE SANTANA CRUDE OIL

TERM:          JANUARY 1, 2001 TO OCTOBER 31, 2001

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 MANUEL IGNACIO DUSSAN VILLAVECES, of legal age,
bearer of citizenship card No. 17.118.200 issued in Bogota, resident in Bogota,
who hereby states: a. That he acts in his capacity as International Trade and
Gas Vice President 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 filed at Notary Public's Office
Seven of Bogota on October 25th, 1983 and registered at the Chamber of Commerce
of Bogota under Registry No. 200848 of November 23rd, 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
Shared 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 27th, 1987
with effective date May 27th, 1987 among ECOPETROL, ARGOSY ENERGY INTERNATIONAL
AND NEO ENERGY INC. It was amended by Public Deed No. 00064 dated January 19th,
1999, filed at Notary Public's Office 50 of Santafe de Bogota.

PARAGRAPH 2: All purchases shall be made by ECOPETROL, under the preliminary
crude oil purchase schedule agreed by the parties for six (6) months periods,
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
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Crude Oil and Fuel Oil Extraction", last revision. c) Crude oil sulfur content
shall be that with which such crude oil is obtained, within production
operations: sulfur determination 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:

<TABLE>
<CAPTION>
          Salt Contents in            Penalty in US       To be covered by
     Pounds per Thousand Barrels      Dollars/Barrel
     <S>                              <C>                 <C>
       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
</TABLE>

It is understood that SELLER shall do its best to deliver the contracted crude
oil, with a salt content 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 8th, 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 ten (10) months
from January 1st, 2001 to October 31st, 2001 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

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Ministry of Mines and Energy shall be the number of gross barrels transported.
The transport tax shall be estimated on the total number of net barrels
transported. The Pipeline Transport Rules shall be considered part to this
Contract once approved by the 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 8th, 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: In the event that no exports of South Blend crude are
made, the following will be taken into consideration:

     a)   If during one month or several consecutive months there are no South
          Blend crude oil exports, the provisional invoicing price shall be the
          price estimated taking as base price, the export price of the previous
          month. In order to estimate the definite price to be used as base
          price, the export price of the crude exports conducted in a month
          following the month or the months for whom the provisional price
          estimate was made, will be used. Once the definite price is estimated,
          the parties will draft the corresponding balance as the case may be.

          The quality adjustment will be estimated using the procedure described
          in Attachment 1.

          In the event that during the last month of the contract and during the
          previous months no exports of South Blend Crude are made, and nor are
          they made during the immediately following month to the last month of
          the contract term, the provisional price estimated for this (these)
          month(s) will be considered as the definite price.

     b)   In the event that no South Blend Crude Oil exports are carried out for
          more than three consecutive months, the provisional invoicing of the
          first three months will be carried out as described in item a)
          hereunder. For deliveries made from the fourth month on, seller can
          only invoice such deliveries until one or several exports of South
          Blend Crude Oil are carried out in one month within the term of the
          contract. For the first three months provisionally invoiced and for
          the months with pending invoicing, the base price shall be the value
          of the aforementioned export(s).

     c)   In the event that during the last month of the contract and during the
          previous months no exports of South Blend Crude are made, and nor are
          they made during the immediately following month to the last month of
          the contract term, the definite prices for deliveries pending
          invoicing will be estimated taking as base prices the prices of the
          last export(s) of South Blend Crude made through the Tumaco Port.
          Quality adjustment of the provisional price and definite price shall
          be estimated according to the procedures described in Attachment 1.
          For the first three months during which no exports were carried out,
          provisions described in item a) hereunder shall apply.

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

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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 they should 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%. 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

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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 at the Santana
Station. Costs of these procedures shall be shared by the parties at a rate
proportionate to  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: 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 NINE: 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 TEN: FORCE MAJEURE. 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 (strikes, mutiny, terrorism,
sabotage, breakage of the pipeline). The obligations that cannot be fulfilled
due to Force Majeure shall be suspended during the term of the Force Majeure
which prevents contract compliance, provided that the party affected by Force
Majeure gives notice to the other party, as soon as possible, using an adequate
means for this purpose, about such situation, with as many details as possible.
Such notice shall be confirmed through a notice sent to the other party within a
forty eight (48) hours term after the Force Majeure event or after the party has
decided to resort to this clause, including all the evidences showing the
occurrence of the Force Majeure event. Once the event is duly proven, the
suspension of the obligations shall be recorded in a Minutes signed by the
Parties. The Party that decides to abide under this item must do its best to
solve the problems preventing it from complying with its obligations. After
overcoming the Force Majeure events, the parties shall sign a minutes verifying
the date when suspended obligations are resumed. Force Majeure shall not relieve
ECOPETROL from its obligation to pay SELLER those invoices filed for the sale of
crude oil delivered by SELLER pursuant to the terms of Clause Three hereunder.

CLAUSE ELEVEN: TERMINATION. This contract can be subject to early termination
for causes imputable to Force Majeure or Acts of God that prevent contract
execution during a term exceeding 90 continuous calendar days.

CLAUSE TWELVE: APPLICATION OF COLOMBIA LAW. For all purposes hereunder, the
parties hereby appoint as contract domicile the city of Bogota D.C., Republic of
Colombia. This contract shall be ruled by the Colombian law and the parties
shall abide 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

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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 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, it 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,
Bogota D.C., Att: Alvaro Jose Camacho R., President. Any address change must be
notified in writing in advance.

In witness whereof this contract is signed in Bogota, D.C., on January 3rd, 2001
in Ecopetrol's Paper.

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EMPRESA COLOMBIANA DE PETROLEOS
Signed: MANUEL IGNACIO DUSSAN VILLAVECES
Vice President
International Trade and Gas

ARGOSY ENERGY INTERNATIONAL
Signed: 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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