NEWSROOM

TORONTO, Nov. 21, 2011 /CNW/ - Pacific Rubiales Energy Corp. (TSX: PRE; BVC: PREC) announced today the end of drilling operations at the Yaraqui-1X well, located in the Topoyaco block, in the foothills of the Putumayo Basin, where the Company has a 50% working interest and is the operator (in both cases subject to ANH approval). The well was drilled to a total depth of 10,651 fee, measured depth (MD), having drilled through the Tertiary and Cretaceous section and penetrating 61 feet into the pre-Cretaceous basement. This well was drilled as part of the original work commitment with the Agencia Nacional de Hidrocarburos (ANH). PetroMagdalena Energy Corp. holds the remaining 50% working interest.

Ronald Pantin, CEO of the Company commented: "Drilling and logging operations to date provide encouraging indications to the potential of the sub-thrust play in the Topoyaco block. This play represents a new exploration horizon for the Company."

The well was spudded on August 31, 2011, and was drilled directionally with a southeast-northwest orientation, in a monocline structure in the sub-thrust of the Topoyaco anticline, and referred to as structure "D". This structure covers an area of approximately 4,500 acres.

According to the petrophysical evaluation of the logs, the well encountered what is interpreted as 142 feet of potential hydrocarbon-bearing sandstones, distributed among the base of the Rumiyaco formation and in the Villeta and Caballos formations, all of which have proven to be commercial reservoirs elsewhere in the basin. In the Rumiyaco Formation, the "Arena Neme" sandstone unit was encountered at 9,714 feet MD (8,801 feet true vertical depth (TVD)) with 20 feet of net oil sandstones with a porosity of 10%. In the Villeta Formation, the pay units were found at 9,748 feet MD (8,828 feet TVD), with a total of 120 feet of potential oil pay: 10 feet in the M2 sandstones encountered at 10,110 feet MD (9,126 feet TVD), 40 feet in the "U" sandstones which start at 10,202 feet MD (9,201 feet TVD) and 70 feet in the "T" sandstones, found at 10,354 feet MD (9,327 feet TVD). The "U" sands have average porosities of 10% while the "T" sands have porosities in the order of 11%. In the Caballos Formation, found at 10,510 feet MD (9,458 feet TVD), a total of 2 feet of potential hydrocarbon sandstones was found, with porosities of 11%.

Currently the Company is preparing to run casing and will proceed to test the well. This evaluation will allow the Company to determine the quality of oil and production potential for the Topoyaco subthrust prospect and to update the prospective resources present in the trap.

Pacific Rubiales, a Canadian-based company and producer of natural gas and heavy crude oil, owns 100 percent of Meta Petroleum Corp., a Colombian oil operator which operates the Rubiales and Piriri oil fields in the Llanos Basin in association with Ecopetrol, S.A., the Colombian national oil company, and 100 percent of Pacific Stratus Energy Corp. which operates the La Creciente natural gas field. The Company is focused on identifying opportunities primarily within the eastern Llanos Basin of Colombia as well as in other areas in Colombia and northern Peru. Pacific Rubiales has working interests in 46 blocks in Colombia, Peru and Guatemala.

The Company's common shares trade on the Toronto Stock Exchange and La Bolsa de Valores de Colombia under the ticker symbols PRE and PREC, respectively. 

Boe may be misleading, particularly if used in isolation. A boe conversion ratio of 5.7 mcf: 1 bbl is based on an energy equivalency conversion method primarily applicable at the burner tip and does not represent a value equivalency at the wellhead. 

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This press release contains forward-looking statements. All statements, other than statements of historical fact, that address activities, events or developments that the company believes, expects or anticipates will or may occur in the future (including, without limitation, statements regarding estimates and/or assumptions in respect of production, revenue, cash flow and costs, reserve and resource estimates, potential resources and reserves and the company's exploration and development plans and objectives) are forward-looking statements. These forward-looking statements reflect the current expectations or beliefs of the company based on information currently available to the company. Forward-looking statements are subject to a number of risks and uncertainties that may cause the actual results of the company to differ materially from those discussed in the forward-looking statements, and even if such actual results are realized or substantially realized, there can be no assurance that they will have the expected consequences to, or effects on the company. Factors that could cause actual results or events to differ materially from current expectations include, among other things: uncertainty of estimates of capital and operating costs, production estimates and estimated economic return; the possibility that actual circumstances will differ from the estimates and assumptions; failure to establish estimated resources or reserves; fluctuations in petroleum prices and currency exchange rates; inflation; changes in equity markets; political developments in Colombia or Peru; changes to regulations affecting the company's activities; uncertainties relating to the availability and costs of financing needed in the future; the uncertainties involved in interpreting drilling results and other geological data; and the other risks disclosed under the heading "Risk Factors" and elsewhere in the company's annual information form dated March 9, 2010 filed on SEDAR at www.sedar.com. Any forward-looking statement speaks only as of the date on which it is made and, except as may be required by applicable securities laws, the company disclaims any intent or obligation to update any forward-looking statement, whether as a result of new information, future events or results or otherwise. Although the company believes that the assumptions inherent in the forward-looking statements are reasonable, forward-looking statements are not guarantees of future performance and accordingly undue reliance should not be put on such statements due to the inherent uncertainty therein.