Mr. Gary Guidry of Gran Tierra reports

GRAN TIERRA ENERGY INC. AND PETROAMERICA OIL CORP. ANNOUNCE AGREEMENT FOR GRAN TIERRA TO ACQUIRE ALL OF PETROAMERICA'S ISSUED AND OUTSTANDING SHARES

Gran Tierra Energy Inc. and Petroamerica Oil Corp. have entered into an arrangement agreement dated Nov. 12, 2015, whereby Gran Tierra has agreed to acquire all of the issued and outstanding common shares of Petroamerica by way of a statutory plan of arrangement under the Business Corporations Act (Alberta).

Under the terms of the arrangement agreement, Petroamerica shareholders will receive, at their election, either 0.40 of a Gran Tierra common share or $1.33 in cash for each Petroamerica share, subject to a maximum of 70 per cent of the consideration payable in cash. If Petroamerica shareholders elect to accept all share consideration, Gran Tierra expects to issue 43.6 million common shares. Gran Tierra will also be assuming the net positive working capital of Petroamerica, estimated at $25-million as at Oct. 31, 2015, after accounting for severance and transaction costs, and including previously restricted cash which Gran Tierra expects to replace with letters of credit. Based on a five-day volume-weighted average trading price of $3.32 per Gran Tierra common share on the facilities of the Toronto Stock Exchange, the transaction value, including working capital, and accounting for severance and transaction costs, is $84-million.

Gran Tierra believes that the acquisition of Petroamerica is highly strategic and will strengthen its position as the premier operator and landholder in the Putumayo basin. Petroamerica's undeveloped landholdings, and exploration and development portfolio are highly complementary to Gran Tierra's own exploration portfolio, strong cash flow, reserve base and balance sheet strength. With expected base pro forma production of 28,000 to 30,000 barrels of oil equivalent per day in 2016, Gran Tierra believes that the combined entity will be uniquely positioned as a high-growth, well-capitalized, Colombia-focused oil and gas producer with a dominant position in the Putumayo basin and a growing presence in the Llanos basin. In addition, Gran Tierra has the financial capacity to pursue additional exploration and development projects within Petroamerica's asset portfolio. The successful completion of the acquisition is expected to be accretive to Gran Tierra's net asset value per share. Gran Tierra will remain debt free with pro forma working capital of $135-million to $210-million, depending on the form of consideration elected by Petroamerica shareholders.

"This transaction is the first step of our corporate strategy to expand and diversify Gran Tierra's oil and gas growth portfolio in Colombia," commented Gary Guidry, Gran Tierra's president and chief executive officer, "and we are very excited to put our cash flow and balance sheet to work on the high quality Petroamerica assets."

Ralph Gillcrist, Petroamerica's president and CEO, commented: "This transaction ensures that the high-quality assets of Petroamerica will be fully developed and the combination with Gran Tierra will create one of the best-positioned companies in the prolific Putumayo and Llanos basins of Colombia. For Petroamerica's shareholders, the resulting pro forma company will bring improved liquidity, increased diversity and scale, an outstanding near-term opportunity set, and most importantly, the financial capability and balance sheet strength to maximize value of Petroamerica's portfolio."

Acquisition highlights:

• Acquisition (before royalty) of 4.5 million barrels of proven and 8.1 million barrels of proven plus probable working interest reserves, based on a National Instrument 51-101-compliant report prepared by GLJ Petroleum Consultants Ltd., as at Dec. 31, 2014;
• Approximately 3,000 boe/d of working interest production, composed of approximately 60-per-cent-Llanos-basin production and 40-per-cent-Putumayo-basin production;
• Approximately 2.2 million gross acres in Colombia (800,000 net acres), including approximately 500,000 gross acres (300,000 net acres) adjacent to or near the company's current acreage in the Putumayo basin, which management believes is prospective for the emerging N sands exploration fairway;
• Enhances near-term exploration drilling inventory;
• Significant opportunity to realize synergistic cost savings through a reduction in general and administrative expenses, and tax planning opportunities.

                        KEY ATTRIBUTES OF THE ACQUISITION

Working interest production (October, 2015, average)               3,000 boe/d
Proved reserves                                                      4.5 mmboe
Proved plus probable reserves                                        8.1 mmboe
Proved plus probable plus possible reserves                         13.1 mmboe
Net working interest acres, October, 2015                        800,000 acres
Tax pools, October, 2015                                          $156 million
Estimated operating netback, October, 2015                      $18 to $20/boe
Estimated annual operating cash flow, 2016          $20-million to $22-million

Acquisition metrics

Based on an estimated purchase price (net of working capital) of $84-million, the acquisition metrics are as shown in the table.

                               ACQUISITION METRICS

Working interest production                         $28,000 per flowing boe
Proved reserves                                              $18.71 per boe
Proved plus probable reserves                                $10.40 per boe
Proved plus probable plus possible reserves                   $6.43 per boe
Cash flow multiple                                         3.8 to 4.2 times
Recycle ratio                                                     1.8 times

Landholdings

The acquisition increases Gran Tierra's position in its core area of Putumayo, including significant additional acreage in the emerging N sands exploration play.

                       PETROAMERICA LAND ACREAGE IN COLOMBIA

                                                      Gross
PTA lands        Block                 Basin        acreage      WI    WI acreage

                 Balay                 Llanos         4,497     15%           675
                 El Eden               Llanos        99,633     40%        39,853
                 El Porton (explor.)   Llanos        99,283    100%        99,283
                 Curiara (El Porton)   Llanos        10,722     25%         2,681
                 LLA-10                Llanos       189,536     50%        94,768
                 LLA-19                Llanos        97,954     50%        48,977
                 Los Maracas           Llanos         5,000     50%         2,500
                 Los Ocarros expl.     Llanos        52,135     50%        26,068
                 CPO-7                 Llanos       627,735     20%       125,547
                 CPO-13                Llanos       466,898     20%        93,380
                 Suroriente            Putumayo      90,263     16%        14,292
                 Alea 1848A            Putumayo      75,764     50%        37,882
                 Alea 1947C            Putumayo      58,068     50%        28,744
                 PUT-7                 Putumayo     130,186     50%        65,093
                 PUT-2                 Putumayo      96,666    100%        96,666
                 PUT-31                Putumayo      34,826     35%        12,189
                 Tinigua               Putumayo     105,466     40%        42,186
Total PTA lands                                   2,244,632     37%       830,783

Strategic rationale

This acquisition is consistent with the company's strategy to efficiently grow its current exploration, development and production opportunity base within Colombia, while diversifying into the prolific Llanos and Magdalena Valley geologic basins. In the company's view it is paying a fair value for the existing reserves and production established by Petroamerica, while at the same time enhancing the combined growth portfolio for both Gran Tierra and Petroamerica shareholders.

"The acquisition is aligned with our strategy of consolidating efforts in our core area of the Putumayo basin where we have a solid land position and a strong operating team. Pro forma for the acquisition, Gran Tierra will be a well-capitalized company with a well-developed production base, free cash flow and a significant growth portfolio providing optionality to allocate capital between three major oil-and-gas-producing basins in Colombia," said Gary Guidry, president and CEO of Gran Tierra. "This acquisition improves the long-term sustainability of our business model not only through diversification and per-share growth, but also through the addition of high-quality assets with significant growth potential. The low-cost, high-return assets add yet another layer of top-quartile locations to our expansive drilling inventory." On a per-share basis, the acquisition is expected to be immediately accretive to Gran Tierra's net asset value per share.

Petroamerica has identified numerous prospects in its exploration portfolio, several of which Gran Tierra intends to drill in 2016. With Gran Tierra's strong balance sheet and forecasted free cash flow generation in 2016, it expects to have the necessary financing to drill the identified prospects. "The acquisition is beneficial to Gran Tierra as it provides the potential to strategically shift its exploration investment commitments from frontier to more proven hydrocarbon-producing basins with established infrastructure and production sales," commented Mr. Guidry.

"Depending on commodity prices and the amount of capital we choose to spend, we believe the Petroamerica assets can contribute approximately 3,000 to 5,000 barrels of oil equivalent per day of production in 2016, over and above our organic growth plans."

The acquisition continues to consolidate Gran Tierra's Putumayo core area, which is expected to generate efficiencies and synergies in the company's consolidated operations and capital program in the area. Although Gran Tierra's strategy is to control capital allocation and operating efficiencies through operatorship, the company can also add significant value as an active joint venture partner. In addition to the new operated Petroamerica assets, Gran Tierra will look to capitalize on the opportunity to transfer its horizontal drilling, completions and waterflood expertise to the non-operated fields.

Gran Tierra maintains a robust balance sheet and is in a strong financial position. The company expects to finance the cash portion of the purchase price, if any, with existing cash on hand. Upon completion of the acquisition, Gran Tierra will have no debt outstanding and an undrawn $200-million (U.S.) bank line.

"Our balance sheet and financial strength allow us to execute on our growth strategy in a low-oil-price environment," said Mr. Guidry. "We are acquiring significant additional N sands resource potential in the Putumayo, while at the same time increasing our footprint in the Llanos basin where we see significant opportunity. Petroamerica's exciting exploration lands are a tremendous fit with Gran Tierra's current land base and are expected to enhance our long-term growth strategy."

Board of directors approvals and recommendations

Petroamerica established a special committee of its board of directors that was tasked to explore various transaction alternatives available to Petroamerica, including transactions similar in nature to the acquisition. Upon receiving an offer from Gran Tierra that was unanimously recommended to the board of directors by the special committee, the board of directors amended the mandate of the special committee to negotiate the acquistion. The special committee, determining that the acquisition was in the best interest of Petroamerica's shareholders, unanimously recommended the acquisition to its board of directors. Upon recommendation of the special committee, the board of directors of Petroamerica, with the exception of one director who recused himself for potential conflict reasons but who unequivocally supports the transaction, has unanimously recommended approval of the acquisition and has determined that the acquisition is in the best interests of Petroamerica shareholders. In addition, Petroamerica's sole financial adviser, Black Spruce Merchant Capital Corp., has provided the board of directors of Petroamerica with a verbal opinion that the consideration to be received by Petroamerica shareholders pursuant to the acquisition is fair, from a financial point of view. Officers, directors and shareholders that collectively hold approximately 10.13 per cent of the issued and outstanding Petroamerica shares have entered into voting support agreements and have agreed to vote their 11,032,858 securities in favour of the acquisition.

The acquisition is subject to Petroamerica shareholder approval, as well as customary regulatory, stock exchange, court and other approvals. The acquisition provides for, among other things, a non-solicitation covenant on the part of Petroamerica, subject to customary fiduciary out provisions that entitle Petroamerica to consider and accept a superior proposal, and gives Gran Tierra the right to match any superior proposal. The arrangement agreement provides for a mutual non-completion fee of $5.0-million (U.S.), payable in certain circumstances, including if Petroamerica enters into an agreement with respect to a superior proposal or if the board of directors of Petroamerica withdraws or modifies its recommendation with respect to the acquisition. The acquisition is expected to close on or about Jan. 29, 2016.

Full details of the acquisition will be included in an information circular of Petroamerica to be mailed to Petroamerica shareholders in accordance with applicable securities laws. A copy of the aforementioned information circular and related documents will be filed under Petroamerica's issuer profile on SEDAR at the applicable time.

Guidance

Gran Tierra continues to execute its business plan of creating sustainable value-added growth in reserves, production and cash flow through management's integrated strategy of acquiring, exploring, developing and enhancing high-quality assets in Colombia.

With an underlying base decline rate of 12 to 15 per cent per year at Costayaco and Moqueta, the company has flexibility to allocate capital to the attractive Petroamerica exploration and development assets. Gran Tierra will provide detailed 2016 budget and forecast guidance in December, 2015.

Advisers

FirstEnergy Capital Corp. and Peters & Co. Ltd. acted as financial advisers to Gran Tierra on the acquisition.

Black Spruce Merchant Capital Corp. acted as sole financial adviser to Petroamerica on the acquisition.

We seek Safe Harbor.