Quantcast
Last updated on April 17, 2014 at 13:47 EDT

Gran Tierra Energy Announces Record 2012 Year-End Reserves

February 4, 2013

Reserve Additions Replace 205% of Production* on a 1P Company Interest
Basis After Producing a Record 8.4 Million Barrels of Oil*

CALGARY, Feb. 4, 2013 /PRNewswire/ - Gran Tierra Energy Inc. (NYSE MKT: GTE; TSX: GTE) (“Gran Tierra Energy“), a company focused on oil exploration and production in South
America, today announced the results of a qualified independent reserve
evaluation of the company’s reserves by GLJ Petroleum Consultants Ltd.
(“GLJ“) effective December 31, 2012.

Year-end 2012 Highlights, calculated in accordance with United States
Securities and Exchange Commission (“SEC“) rules (comparisons are to 2011 year-end amounts):

        --  Total Proved ("1P") reserves net after royalty ("NAR")
            increased 20% to approximately 40.6 million barrels of oil
            equivalent ("MMBOE") (approximately 95% light and medium oil
            and liquids; an increase compared to 91% at year-end 2011);
        --  Total Proved plus Probable ("2P") reserves NAR increased 15% to
            approximately 56.2 MMBOE (approximately 95% light and medium
            oil and liquids; an increase compared to 85% at year-end 2011);
        --  Total Proved plus Probable plus Possible ("3P") reserves NAR
            increased 1% to approximately 86.3 MMBOE (approximately 87%
            light and medium oil and liquids; an increase compared to 69%
            at year-end 2011);
        --  Reservoir performance expectations were exceeded at the
            Costayaco field in Colombia.  Costayaco 1P reserves increased
            to 19.7 million barrels of oil ("MMBO") NAR at year-end 2012
            from 16.4 MMBO NAR at year-end 2011 despite total production of
            3.8 MMBO NAR before inventory adjustments in 2012;
        --  Appraisal drilling in the Moqueta field in Colombia resulted in
            1P reserves increasing 45% to approximately 8.7 MMBO, 2P
            reserves increasing 54% to 14.9 MMBO and 3P reserves increasing
            108% to 26.9 MMBO on a company interest basis, and 1P reserves
            increasing to approximately 6.8 MMBO, 2P reserves increasing to
            11.2 MMBO and 3P reserves increasing to 19.4 MMBO on a NAR
            basis.  The limits of the field have not yet been defined;
        --  Gran Tierra Energy produced approximately 8.4 MMBO of working
            interest oil before royalties and inventory adjustments or 6.4
            MMBO NAR before inventory adjustments and 1.7 billion cubic
            feet ("Bcf") of company interest gas before royalties or 1.5
            Bcf NAR in 2012;
        --  Based on Gran Tierra Energy's 2012 year-end SEC company
            interest reserves and Gran Tierra Energy's 2012 total working
            interest production, Gran Tierra Energy's 1P, 2P, and 3P
            reserves life indices are 6.4 years, 8.9 years, and 13.6 years
            respectively.
        --  Annual production for 2012 averaged a record of approximately
            23,600company interest barrels of oil equivalent per day
            ("BOEPD") before royalties, or 18,000 BOEPD NAR, both before
            inventory adjustments.  Production in the fourth quarter of
            2012 increased to approximately 18,600 BOEPD NAR before
            inventory adjustments.  Production for the month of January
            2013, before inventory adjustments, increased further to
            average approximately 21,000 BOEPD NAR.

All reserves values contained in the 2012 Highlights provided above have
been calculated using SEC rules.  For reserves values calculated in
compliance with Canadian National Instrument 51-101 – Standards of Disclosure for Oil and Gas Activities (“NI 51-101“) and the Canadian Oil and Gas Evaluation Handbook (“COGEH“), see “Reserves Reported in Accordance with Canadian Reporting
Requirements” below in this press release.

* Before royalties and inventory adjustments

“Through continued strong reservoir management, appraisal drilling and
exploration success, Gran Tierra Energy had another outstanding year in
growing reserves and production to record levels from our projects in
Colombia, Brazil and Argentina. The company has been successful at
consistently growing land, reserves and production over the past 8
years and is focused on continuing to add value for our shareholders
through successful exploration and development drilling in the future,”
said Dana Coffield, President and CEO. “In 2012, we produced a record
volume of oil, in spite of unexpected challenges posed by substantial
transportation downtime due to pipeline disruptions on the OTA pipeline
in Colombia.  Our team has worked vigorously to put into place
alternative transportation measures to mitigate possible future
downtime impacts to crude transportation.  These measures are now in
place and operational. As a result, even with recent disruptions, the
company achieved near record levels of production, before inventory
adjustments, in January of this year.”

“In 2013, we are focused on continuing to grow reserves through
continued appraisal drilling in the Moqueta and Ramiriqui oil
discoveries, and additional exploration drilling in Colombia, testing
new oil resource play concepts in Brazil and Argentina, and evaluating
a very high-impact oil exploration target at the recently drilled
Bretaña Norte well in Peru. Gran Tierra Energy’s 2013 capital budget is
expected to be funded through available cash on hand, cash flow from
operations and with potential periodic draws on our credit facility at
current commodity prices and production levels,” concluded Coffield.

Reserves Reported in Accordance with United States Reporting
Requirements

The following reserves are reported consistent with United States
Securities and Exchange Commission rules.

Total Company

The following two tables summarize Gran Tierra Energy’s year-end 2012
company interest reserves and NAR reserves (calculated using average
start-of-month 2012 oil prices). Also shown in the following table are
Gran Tierra Energy’s NAR reserves for year-end 2011 (calculated using
average start-of-month 2011 oil prices).

     ___________________________________________________________________
    |Total Company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(SEC Compliant)  |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|       MBO **   |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       35,644   |     26,817  |         21,317   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         778    |       666   |         1,554    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |       14,280   |     11,011  |         8,051    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       50,702   |     38,494  |         30,922   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       19,641   |     14,784  |         10,489   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       70,343   |     53,278  |         41,411   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       28,418   |     21,456  |         17,626   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       98,761   |     74,734  |         59,037   |
    |_________________|________________|_____________|__________________|

**MBO (thousand barrels of oil).

     ___________________________________________________________________
    |Total Company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(SEC Compliant)  |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|      MMSCF***  |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       11,572   |     10,515  |         16,968   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        1,014   |       813   |           310    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        1,624   |      1,448  |         1,044    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       14,210   |     12,776  |         18,322   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        6,087   |      5,136  |         25,716   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       20,297   |     17,912  |         44,038   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       59,375   |     51,667  |        116,509   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       79,672   |     69,579  |        160,547   |
    |_________________|________________|_____________|__________________|

***MMSCF (million standard cubic feet)

     ___________________________________________________________________
    |Total Company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |BOE              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(SEC Compliant)  |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|      BOE****   |       BOE   |           BOE    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       37,572   |     28,569  |         24,145   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         947    |       802   |         1,606    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |       14,551   |     11,252  |         8,225    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       53,070   |     40,623  |         33,976   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       20,656   |     15,640  |         14,775   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       73,726   |     56,263  |         48,751   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       38,314   |     30,068  |         37,044   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |      112,040   |     86,331  |         85,795   |
    |_________________|________________|_____________|__________________|

****BOE (barrel of oil equivalent).

        --  1P, 2P and 3P reserves NAR (on an oil equivalent basis)
            increased largely due to positive technical adjustment to
            Costayaco reserves based on reservoir performance and
            additional appraisal drilling at Moqueta in Colombia.
        --  Reserves were added through the Ramiriqui-1 exploration well in
            Colombia.
        --  Reserves were added through development drilling in the Tiê
            field in the Recôncavo Basin, Brazil.
        --  The Proa-2 development well on the Surubi Block, Argentina,
            successfully added reserves.
        --  Partially offsetting reserve additions was 2012 full year
            production of 8.4 MMBO of company interest oil before royalties
            and 1.7 Bcf of company interest gas before royalties.

Colombia

Gran Tierra Energy’s Colombia year-end 2012 company interest and NAR
reserves are shown in the following two tables (calculated using
average start-of-month 2012 oil prices). Also shown in the following
two tables is Gran Tierra Energy’s Colombian NAR reserves for year-end
2011 (calculated using average start-of-month 2011 oil prices).

     ___________________________________________________________________
    |Colombia         | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(SEC Compliant)  |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       32,838   |     24,360  |         19,497   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         380    |       317   |         1,402    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        8,989   |      6,432  |         4,526    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       42,207   |     31,109  |         25,425   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       15,178   |     10,915  |         5,913    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       57,385   |     42,024  |         31,338   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       18,839   |     13,167  |         9,749    |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       76,224   |     55,191  |         41,087   |
    |_________________|________________|_____________|__________________|

 

     ___________________________________________________________________
    |Colombia         | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(SEC Compliant)  |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|        MMSCF   |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        8,370   |      7,757  |         13,927   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         993    |       794   |            0     |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        1,012   |       921   |           713    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       10,375   |      9,472  |         14,640   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        3,929   |      3,300  |         21,155   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       14,304   |     12,772  |         35,795   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        5,353   |      4,239  |         72,026   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       19,657   |     17,011  |        107,821   |
    |_________________|________________|_____________|__________________|
        --  The increase in 1P, 2P and 3P NAR oil reserves is mainly
            associated with positive technical adjustments in Costayaco
            reserves due to reservoir performance, additional development
            drilling in Costayaco, the appraisal drilling program in
            Moqueta field in Colombia, and the Ramiriqui-1 exploration
            well.

The Costayaco and Moqueta fields 2012 year-end NAR reserves are shown in
the following two tables (calculated using average start-of-month 2012
oil prices). Also shown in the following two tables is a comparison of
the Costayaco and Moqueta fields 2012 year-end gross lease reserves
(calculated using average start-of-month 2012 oil prices) to the gross
lease reserves estimated in December 31, 2011 (calculated using average
start-of-month 2011 oil prices).

     ___________________________________________________________________
    |Costayaco            |2012 Year-End| 2012 Year-End | 2011 Year-End |
    |                     |             |               |               |
    |Light and Medium Oil |Costayaco NAR|Costayaco Gross|Costayaco Gross|
    |                     |  Reserves   |Lease Reserves |Lease Reserves |
    |(SEC Compliant)      |             |               |               |
    |_____________________|_____________|_______________|_______________|
    |Reserves Category    |       MBO   |         MBO   |         MBO   |
    |_____________________|_____________|_______________|_______________|
    |Proved               |             |               |               |
    |_____________________|_____________|_______________|_______________|
    |  Developed Producing|     17,240  |      24,803   |      20,281   |
    |_____________________|_____________|_______________|_______________|
    |Total Proved         |     19,716  |      28,424   |      23,517   |
    |_____________________|_____________|_______________|_______________|
    |Total Probable       |      3,740  |       5,420   |       2,503   |
    |_____________________|_____________|_______________|_______________|
    |Total Proved plus    |     23,456  |      33,844   |      26,020   |
    |Probable             |             |               |               |
    |_____________________|_____________|_______________|_______________|
    |Total Possible       |      2,642  |       3,867   |       7,528   |
    |_____________________|_____________|_______________|_______________|
    |Total PPP            |     26,098  |      37,711   |      33,548   |
    |_____________________|_____________|_______________|_______________|

 

     _____________________________________________________________________
    |Moqueta             |2012 Year-End|   2012 Year-End   |2011 Year-End |
    |                    |             |                   |              |
    |Light and Medium Oil| Moqueta NAR |Moqueta Gross Lease|Moqueta Gross |
    |                    |  Reserves   |     Reserves      |Lease Reserves|
    |(SEC Compliant)     |             |                   |              |
    |____________________|_____________|___________________|______________|
    |Reserves Category   |       MBO   |            MBO    |        MBO   |
    |____________________|_____________|___________________|______________|
    |Proved              |             |                   |              |
    |____________________|_____________|___________________|______________|
    |  Developed         |      3,745  |          4,250    |      2,137   |
    |Producing           |             |                   |              |
    |____________________|_____________|___________________|______________|
    |Total Proved        |      6,849  |          8,683    |      5,973   |
    |____________________|_____________|___________________|______________|
    |Total Probable      |      4,314  |          6,252    |      3,727   |
    |____________________|_____________|___________________|______________|
    |Total Proved plus   |     11,163  |         14,935    |      9,700   |
    |Probable            |             |                   |              |
    |____________________|_____________|___________________|______________|
    |Total Possible      |      8,262  |         11,922    |      3,243   |
    |____________________|_____________|___________________|______________|
    |Total PPP           |     19,425  |         26,857    |      12,943  |
    |____________________|_____________|___________________|______________|
        --  Gran Tierra Energy successfully completed development drilling
            at Costayaco-15, Costayaco-16 and Costayaco-17 in 2012.
        --  Approximately 3.8 MMBO NAR before inventory adjustments was
            produced from the Costayaco field in 2012. Through a successful
            field development and reservoir management program in 2012,
            Gran Tierra Energy was able to successfully mitigate reserve
            declines at the Costayaco field.
        --  Gran Tierra Energy successfully drilled the Moqueta-7 and
            Moqueta-8 appraisal wells in 2012.

Argentina

Gran Tierra Energy’s Argentina company interest and NAR reserves are
shown in the following two tables (calculated using average
start-of-month 2012 oil prices). Also shown in the following two tables
is Gran Tierra Energy’s Argentina NAR reserves for year-end 2011
(calculated using average start-of-month 2011 oil prices).

     ___________________________________________________________________
    |Argentina        | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(SEC Compliant)  |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        2,407   |      2,110  |         1,766    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         398    |       349   |           152    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        3,868   |      3,335  |         3,226    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        6,673   |      5,794  |         5,144    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        2,929   |      2,530  |         3,389    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        9,602   |      8,324  |         8,533    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        7,211   |      6,219  |         5,842    |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       16,813   |     14,543  |         14,375   |
    |_________________|________________|_____________|__________________|

     ___________________________________________________________________
    |Argentina        | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(SEC Compliant)  |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|        MMSCF   |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        3,202   |      2,758  |         3,041    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |          21    |        19   |           310    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |         612    |       527   |           331    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        3,835   |      3,304  |         3,682    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        2,158   |      1,836  |         4,561    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        5,993   |      5,140  |         8,243    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       54,022   |     47,428  |         44,483   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       60,015   |     52,568  |         52,726   |
    |_________________|________________|_____________|__________________|
        --  The 1P and 3P NAR liquid reserve additions are largely
            associated with positive adjustments at Puesto Morales and
            Surubi.

Brazil

Gran Tierra Energy’s Brazil company interest and NAR reserves are shown
in the following table (calculated using average start-of-month 2012
oil prices). Also shown in the following table is Gran Tierra Energy’s
Brazil NAR reserves for year-end 2011 (calculated using average
start-of-month 2011 oil prices).

     ___________________________________________________________________
    |Brazil           | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(SEC Compliant)  |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         399    |       347   |            54    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |           0    |         0   |            0     |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        1,423   |      1,244  |           299    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        1,822   |      1,591  |           353    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        1,534   |      1,339  |         1,187    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        3,356   |      2,930  |         1,540    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        2,368   |      2,070  |         2,035    |
    |_________________|________________|_____________|__________________|
    |Total PPP        |        5,724   |      5,000  |         3,575    |
    |_________________|________________|_____________|__________________|
        --  1P, 2P and 3P reserves were added through development drilling
            in Brazil and increasing working interest to 100% from 70% in
            Blocks REC-T-129, -142, -155 and -224 located in Brazil's
            Recôncavo Basin.

Reserves Reported in Accordance with Canadian Reporting Requirements

The following reserves estimates are compliant with NI 51-101 and COGEH
(with forecasted oil price and costs):

Total Company

     ___________________________________________________________________
    |Total company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(NI 51-101       |                |             |                  |
    |compliant)       |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       35,242   |     26,892  |         21,232   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         510    |       444   |         1,293    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |       13,996   |     10,920  |         8,448    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       49,748   |     38,256  |         30,973   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       19,528   |     15,006  |         10,601   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       69,276   |     53,262  |         41,574   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       28,755   |     22,105  |         18,224   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       98,031   |     75,367  |         59,798   |
    |_________________|________________|_____________|__________________|

     ___________________________________________________________________
    |Total Company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(NI-51-101       |Company Interest|NAR Reserves |                  |
    |Compliant)       |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|        MMSCF   |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       11,572   |     10,515  |         16,971   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        1,014   |       812   |           306    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        1,483   |      1,327  |         1,045    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       14,069   |     12,654  |         18,322   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        6,480   |      5,550  |         25,721   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       20,549   |     18,204  |         44,043   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       59,086   |     51,529  |        116,519   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       79,635   |     69,733  |        160,562   |
    |_________________|________________|_____________|__________________|

 

     ___________________________________________________________________
    |Total Company    | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |BOE              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(NI-51-101       |Company Interest|NAR Reserves |                  |
    |Compliant)       |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         BOE    |       BOE   |           BOE    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       37,171   |     28,645  |         24,061   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         679    |       579   |         1,344    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |       14,243   |     11,141  |         8,622    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       52,093   |     40,365  |         34,027   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       20,608   |     15,931  |         14,888   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       72,701   |     56,296  |         48,915   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       38,603   |     30,693  |         37,644   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |      111,304   |     86,989  |         86,558   |
    |_________________|________________|_____________|__________________|

Colombia

Gran Tierra Energy’s year-end 2012 Colombia company interest and NAR
liquid reserves are shown in the following table (NI 51-101 compliant
with forecast oil price and cost). Also shown in the following table
are Gran Tierra Energy’s Colombian NAR reserves for year-end 2011 (NI
51-101 compliant with forecast oil price and cost).

     ___________________________________________________________________
    |Colombia         | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(NI 51-101       |                |             |                  |
    |compliant)       |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |       32,437   |     24,436  |         19,373   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         112    |        96   |         1,141    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        8,805   |      6,427  |         4,934    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       41,354   |     30,959  |         25,448   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |       14,966   |     11,055  |         6,029    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       56,320   |     42,014  |         31,477   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       19,175   |     13,820  |         10,196   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       75,495   |     55,834  |         41,673   |
    |_________________|________________|_____________|__________________|

Gran Tierra Energy’s year-end 2012 Colombia company interest and NAR gas
reserves are shown in the following table (NI 51-101 compliant with
forecast gas price and cost). Also shown in the following table are
Gran Tierra Energy’s Colombian NAR reserves for year-end 2011 (NI
51-101 compliant with forecast gas price and cost).

     ___________________________________________________________________
    |Colombia         | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(NI-51-101       |Company Interest|NAR Reserves |                  |
    |Compliant)       |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|        MMSCF   |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        8,371   |      7,757  |         13,926   |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         993    |       794   |            0     |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |         980    |       892   |           714    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |       10,344   |      9,443  |         14,640   |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        4,213   |      3,621  |         21,156   |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|       14,557   |     13,064  |         35,796   |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        5,063   |      4,102  |         72,026   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       19,620   |     17,166  |        107,822   |
    |_________________|________________|_____________|__________________|

The Costayaco and Moqueta fields 2012 year-end NAR reserves are shown in
the following two tables (with forecast oil price and cost). Also shown
in the following two tables is a comparison of the Costayaco and
Moqueta fields 2012 year-end gross lease reserves (with forecast oil
price and cost) to the gross lease reserves estimated at December 31,
2011 (with forecast oil price and cost).

     ___________________________________________________________________
    |Costayaco           |2012 Year-End | 2012 Year-End | 2011 Year-End |
    |                    |              |               |               |
    |Light and Medium Oil|Costayaco Gran|Costayaco Gross|Costayaco Gross|
    |                    |    Tierra    |Lease Reserves |Lease Reserves |
    |(NI 51-101          |  Energy NAR  |               |               |
    |compliant)          |   Reserves   |               |               |
    |____________________|______________|_______________|_______________|
    |Reserves Category   |        MBO   |         MBO   |         MBO   |
    |____________________|______________|_______________|_______________|
    |Proved              |              |               |               |
    |____________________|______________|_______________|_______________|
    |  Developed         |      17,415  |      24,535   |      19,855   |
    |Producing           |              |               |               |
    |____________________|______________|_______________|_______________|
    |Total Proved        |      19,929  |      28,139   |      23,216   |
    |____________________|______________|_______________|_______________|
    |Total Probable      |      3,572   |       5,067   |       2,496   |
    |____________________|______________|_______________|_______________|
    |Total Proved plus   |      23,501  |      33,206   |      25,712   |
    |Probable            |              |               |               |
    |____________________|______________|_______________|_______________|
    |Total Possible      |      2,655   |       3,799   |       7,836   |
    |____________________|______________|_______________|_______________|
    |Total PPP           |      26,156  |      37,005   |      33,548   |
    |____________________|______________|_______________|_______________|

 

     _________________________________________________________________
    |Moqueta              |2012 Year-End|2012 Year-End |2011 Year-End |
    |                     |             |              |              |
    |Light and Medium Oil | Moqueta NAR |Moqueta Gross |Moqueta Gross |
    |                     |  Reserves   |Lease Reserves|Lease Reserves|
    |(NI 51-101 compliant)|             |              |              |
    |                     |             |              |              |
    |_____________________|_____________|______________|______________|
    |Reserves Category    |       MBO   |        MBO   |        MBO   |
    |_____________________|_____________|______________|______________|
    |Proved               |             |              |              |
    |_____________________|_____________|______________|______________|
    |  Developed Producing|      3,709  |      4,190   |      2,137   |
    |_____________________|_____________|______________|______________|
    |Total Proved         |      6,794  |      8,478   |      5,973   |
    |_____________________|_____________|______________|______________|
    |Total Probable       |      4,586  |      6,457   |      3,727   |
    |_____________________|_____________|______________|______________|
    |Total Proved plus    |     11,380  |      14,935  |      9,700   |
    |Probable             |             |              |              |
    |_____________________|_____________|______________|______________|
    |Total Possible       |      8,501  |      11,922  |      3,243   |
    |_____________________|_____________|______________|______________|
    |Total PPP            |     19,881  |      26,857  |      12,943  |
    |_____________________|_____________|______________|______________|

Argentina

Gran Tierra Energy’s Argentina year-end 2012 company interest and NAR
liquid reserves are shown in the following table (NI 51-101 compliant
with forecast oil price and cost). Also shown in the following table is
Gran Tierra Energy’s Argentina NAR reserves for year-end 2011 (NI
51-101 compliant with forecast oil price and cost).

     ___________________________________________________________________
    |Argentina        | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(NI 51-101       |                |             |                  |
    |compliant)       |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        2,406   |      2,109  |         1,803    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         398    |       348   |           152    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        3,768   |      3,251  |         3,226    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        6,572   |      5,708  |         5,181    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        3,028   |      2,615  |         3,420    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        9,600   |      8,323  |         8,601    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        7,212   |      6,220  |         5,977    |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       16,812   |     14,543  |         14,578   |
    |_________________|________________|_____________|__________________|

Gran Tierra Energy’s Argentina year-end 2012 company interest and NAR
gas reserves are shown in the following table (NI 51-101 compliant with
forecast oil price and cost). Also shown in the following table is Gran
Tierra Energy’s Argentina NAR reserves for year-end 2011 (NI 51-101
compliant with forecast oil price and cost).

     ___________________________________________________________________
    |Argentina        | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Gas              |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |                 |     Energy     |   Energy    |   NAR Reserves   |
    |(NI-51-101       |Company Interest|NAR Reserves |                  |
    |Compliant)       |    Reserves    |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|        MMSCF   |      MMSCF  |         MMSCF    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |        3,201   |      2,758  |         3,045    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |          21    |        18   |           306    |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |         503    |       435   |           331    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        3,725   |      3,211  |         3,682    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        2,267   |      1,929  |         4,565    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        5,992   |      5,140  |         8,247    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |       54,023   |     47,427  |         44,493   |
    |_________________|________________|_____________|__________________|
    |Total PPP        |       60,015   |     52,567  |         52,740   |
    |_________________|________________|_____________|__________________|

Brazil

Gran Tierra Energy’s Brazil year-end 2012 company interest and NAR
liquid reserves are shown in the following table (NI 51-101 compliant
with forecast oil price and cost).

     ___________________________________________________________________
    |Brazil           | 2012 Year-End  |2012 Year-End|  2011 Year-End   |
    |                 |                |             |                  |
    |Light and Medium |  Gran Tierra   | Gran Tierra |Gran Tierra Energy|
    |Oil and          |     Energy     |   Energy    |   NAR Reserves   |
    |Liquids          |Company Interest|NAR Reserves |                  |
    |                 |    Reserves    |             |                  |
    |(NI 51-101       |                |             |                  |
    |compliant)       |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Reserves Category|         MBO    |       MBO   |           MBO    |
    |_________________|________________|_____________|__________________|
    |Proved           |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |         399    |       347   |            56    |
    |Producing        |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Developed      |           0    |         0   |            0     |
    |Nonproducing     |                |             |                  |
    |_________________|________________|_____________|__________________|
    |  Undeveloped    |        1,423   |      1,242  |           288    |
    |_________________|________________|_____________|__________________|
    |Total Proved     |        1,822   |      1,589  |           344    |
    |_________________|________________|_____________|__________________|
    |Total Probable   |        1,534   |      1,336  |         1,152    |
    |_________________|________________|_____________|__________________|
    |Total Proved plus|        3,356   |      2,925  |         1,496    |
    |Probable         |                |             |                  |
    |_________________|________________|_____________|__________________|
    |Total Possible   |        2,368   |      2,065  |         2,051    |
    |_________________|________________|_____________|__________________|
    |Total PPP        |        5,724   |      4,990  |         3,547    |
    |_________________|________________|_____________|__________________|

About Gran Tierra Energy Inc.

Gran Tierra Energy Inc. is an international oil and gas exploration and
production company, headquartered in Calgary, Canada, incorporated in
the United States, trading on the NYSE MKT Exchange (GTE) and the
Toronto Stock Exchange (GTE), and operating in South America. Gran
Tierra Energy holds interests in producing and prospective properties
in Argentina, Colombia, Peru and Brazil. Gran Tierra Energy has a
strategy that focuses on establishing a portfolio of producing
properties, plus production enhancement and exploration opportunities
to provide a base for future growth.

Additional information concerning Gran Tierra Energy is available at www.grantierra.com, on SEDAR (www.sedar.com and with the SEC www.sec.gov).

Cautionary Statements:

Possible reserves are those additional reserves that are less certain to
be recovered than Probable reserves. There is a 10% probability that
the quantities actually recovered will equal or exceed the sum of
Proved plus Probable plus Possible reserves. The estimate of reserves
for individual properties may not reflect the same confidence level as
estimates of reserves for all properties, due to the effects of
aggregation.  A BOE is calculated using the conversion factor of six thousand cubic feet (“Mcf“) of natural gas being equivalent to one barrel of oil. BOEs may be
misleading, particularly if used in isolation.  A BOE conversion ratio
of 6 Mcf : 1 barrel of oil is based on an energy equivalency conversion
method primarily applicable at the burner tip and does not represent a
value equivalency at the wellhead.

Forward-Looking Statements

The statements in this press release regarding Gran Tierra Energy’s
expectations, plans, projections and actions including, reserve life
index, Gran Tierra Energy’s expectations regarding its 2013 exploration
and development drilling campaign, reservoir management and production,
and expected funding of Gran Tierra Energy’s 2013 capital program are
“forward-looking statements” within the meaning of the U.S. federal and
Canadian securities laws, including Canadian Securities Administrators’
National Instrument 51-102 – Continuous Disclosure Obligations and the U.S. Private Securities Litigation Reform Act of 1995.
Statements containing the words “estimates”, “expects”, “continue”,
“will”, “may”, “grow”, “anticipated” and variations of these words are
forward-looking statements. 

The forward-looking statements contained in this news release reflect
several material factors and expectations and assumptions of Gran
Tierra Energy including, without limitation, assumptions relating to
the accuracy of its reserves estimates, the continuity of certain
industry conditions, the ability of Gran Tierra Energy to execute its
current business and operational plans in the manner currently planned.
Although Gran Tierra Energy believes that the assumptions underlying,
and expectations reflected in, these forward-looking statements are
reasonable, it can give no assurance that these assumptions and
expectations will prove to be correct. 

The forward-looking statements contained in this press release are
subject to risks, uncertainties and other factors that could cause
actual results or outcomes to differ materially from those contemplated
by the forward-looking statements. Factors that could cause results to
differ materially from those described in the forward-looking
statements include: Gran Tierra Energy’s operations are located in
South America, and unexpected problems can arise due to guerilla
activity, technical difficulties and operational difficulties which
impact the production, transportation or sale of oil and gas; changing
prices for crude oil may cause some scheduled projects or actions to
become uneconomical, or may change Gran Tierra Energy’s focus to other
projects or actions which could be of more benefit to Gran Tierra
Energy, which could cause projects or actions currently contemplated to
be postponed or cancelled; unexpected problems due to technical
difficulties, operational difficulties, and weather conditions; risks
associated with not being able to fund the 2013 capital program through
cash flow and cash on hand; and those other risks found in the periodic
reports filed by Gran Tierra Energy with the SEC, including in the
section entitled “Risk Factors” in its Quarterly Report on Form 10-Q
filed with the SEC on November 7, 2012, and available at the SEC’s
internet site www.sec.gov and on SEDAR at www.sedar.com.

All forward-looking statements in this press release are expressly
qualified by information contained in Gran Tierra Energy’s filings with
regulatory authorities and, subject to its obligations under applicable
securities laws, Gran Tierra Energy does not undertake to publicly
update forward-looking statements, whether as a result of new
information, future events or otherwise.

SOURCE Gran Tierra Energy Inc.


Source: PR Newswire