Exhibit 99.1

DeGolyer and MacNaughton

5001 Spring Valley Road

Suite 800 East

Dallas, Texas 75244

March 2, 2010

TransAtlantic Petroleum Ltd.

5910 N. Central Expressway

Suite 1755

Dallas, Texas 75206

Gentlemen:

Pursuant to your
request, we have prepared estimates of the extent and value of the net proved crude oil and natural gas reserves, as of December 31, 2009, of certain properties owned by TransAtlantic Petroleum Ltd. (TransAtlantic). The properties appraised
consist of working interests located in the Arpatepe, Edirne, and Selmo fields in Turkey. TransAtlantic has represented that these properties account for 100 percent of TransAtlantics net proved reserves as of December 31, 2009.

Estimates of proved reserves presented in this report have been prepared in compliance with the regulations promulgated by
the United States Securities and Exchange Commission (SEC). These reserves definitions are discussed in detail in the Definition of Reserves section of this report.

Reserves included herein are expressed as net reserves. Gross reserves are defined as the total estimated petroleum to be produced from these properties after December 31, 2009. Net reserves are
defined as that portion of the gross reserves attributable to the interests owned by TransAtlantic after deducting all interests owned by others. Gas quantities estimated herein are expressed as sales gas. Sales gas is defined as that portion of the
total gas to be delivered into a gas pipeline for sale after separation, processing, fuel use, and flare. Gas reserves are expressed at a temperature base of 60 degrees Fahrenheit (°F) and at a pressure base of 14.70 pounds per square inch
absolute (psia). Condensate reserves estimated herein are those to be recovered by conventional lease separation.



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Values of proved reserves shown herein are expressed in terms of estimated future gross
revenue, future net revenue, and present worth. Future gross revenue is that revenue which will accrue to the appraised interests from the production and sale of the estimated net reserves. Future net revenue is calculated by deducting estimated
severance taxes, ad valorem taxes, operating expenses, and capital costs from the future gross revenue. Operating expenses include field operating expenses, transportation expenses, compression charges, and an allocation of overhead that directly
relates to production activities. Future income tax expenses were not taken into account in the preparation of these estimates. Present worth is defined as future net revenue discounted at a specified arbitrary discount rate compounded monthly over
the expected period of realization.

Estimates of oil and natural gas should be regarded only as estimates that may change as
further production history and additional information become available. Not only are such reserves estimates based on that information which is currently available, but such estimates are also subject to the uncertainties inherent in the application
of judgmental factors in interpreting such information.

Data used in this audit were obtained from reviews with TransAtlantic
personnel, TransAtlantic files, from records on file with the appropriate regulatory agencies, and from public sources. In the preparation of this report we have relied, without independent verification, upon such information furnished by
TransAtlantic with respect to property interests, production from such properties, current costs of operation and development, current prices for production, agreements relating to current and future operations and sale of production, and various
other information and data that were accepted as represented. A field examination of the properties was not considered necessary for the purposes of this report.

Methodology and Procedures

Estimates of reserves were prepared by
the use of standard geological and engineering methods generally accepted by the petroleum industry. The method or combination of methods used in the analysis of each reservoir was tempered by experience with similar reservoirs, stage of
development, quality and completeness of basic data, and production history.

When applicable, the volumetric method was used
to estimate the original oil in place (OOIP) and the original gas in place (OGIP). Structure and isopach maps were constructed to estimate reservoir volume. Electrical logs, radioactivity logs, core analyses, and other available data were used to
prepare these maps as well as to estimate representative values for porosity and water saturation. When adequate data were available and when circumstances justified, material balance and other engineering methods were used to estimate OOIP or OGIP.



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Estimates of ultimate recovery were obtained after applying recovery factors to OOIP or
OGIP. These recovery factors were based on consideration of the type of energy inherent in the reservoirs, analyses of the petroleum, the structural positions of the properties, and the production histories. When applicable, material balance and
other engineering methods were used to estimate recovery factors. An analysis of reservoir performance, including production rate, reservoir pressure, and gas-oil ratio behavior, was used in the estimation of reserves.

For depletion-type reservoirs or those whose performance disclosed a reliable decline in producing-rate trends or other diagnostic
characteristics, reserves were estimated by the application of appropriate decline curves or other performance relationships. In the analyses of production-decline curves, reserves were estimated only to the limits of economic production or to the
limit of the production licenses as appropriate.

Definition of Reserves

Petroleum reserves included in this report are classified as proved. Only proved reserves have been evaluated for this report. Reserves
classifications used in this report are in accordance with the reserves definitions of Rules 410(a) (1)(32) of Regulation SX of the SEC. Reserves are judged to be economically producible in future years from known reservoirs
under existing economic and operating conditions and assuming continuation of current regulatory practices using conventional production methods and equipment. In the analyses of production-decline curves, reserves were estimated only to the limit
of economic rates of production under existing economic and operating conditions using prices and costs consistent with the effective date of this report, including consideration of changes in existing prices provided only by contractual
arrangements but not including escalations based upon future conditions. The petroleum reserves are classified as follows:

Proved oil and gas reserves  Proved oil and gas reserves are those quantities of oil and gas, which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty to be economically
produciblefrom a given date forward, from known reservoirs, and under existing economic conditions, operating methods, and government regulationsprior to the time at which contracts providing the right to operate expire, unless evidence
indicates that renewal is reasonably certain, regardless of whether deterministic or probabilistic methods are used for the estimation. The project to extract the hydrocarbons must have commenced or the operator must be reasonably certain that it
will commence the project within a reasonable time.



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(i) The area of the reservoir considered as proved includes: (A) The area identified by
drilling and limited by fluid contacts, if any, and (B) Adjacent undrilled portions of the reservoir that can, with reasonable certainty, be judged to be continuous with it and to contain economically producible oil or gas on the basis of
available geoscience and engineering data.

(ii) In the absence of data on fluid contacts, proved quantities in a reservoir are
limited by the lowest known hydrocarbons (LKH) as seen in a well penetration unless geoscience, engineering, or performance data and reliable technology establishes a lower contact with reasonable certainty.

(iii) Where direct observation from well penetrations has defined a highest known oil (HKO) elevation and the potential exists for an
associated gas cap, proved oil reserves may be assigned in the structurally higher portions of the reservoir only if geoscience, engineering, or performance data and reliable technology establish the higher contact with reasonable certainty.

(iv) Reserves which can be produced economically through application of improved recovery techniques (including, but not
limited to, fluid injection) are included in the proved classification when:

(A) Successful testing by a pilot project in an
area of the reservoir with properties no more favorable than in the reservoir as a whole, the operation of an installed program in the reservoir or an analogous reservoir, or other evidence using reliable technology establishes the reasonable
certainty of the engineering analysis on which the project or program was based; and (B) The project has been approved for development by all necessary parties and entities, including governmental entities.



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(v) Existing economic conditions include prices and costs at which economic
producibility from a reservoir is to be determined. The price shall be the average price during the 12-month period prior to the ending date of the period covered by the report, determined as an unweighted arithmetic average of the
first-day-of-the-month price for each month within such period, unless prices are defined by contractual arrangements, excluding escalations based upon future conditions.

Developed oil and gas reserves  Developed oil and gas reserves are reserves of any category that can be expected to be recovered:

(i) Through existing wells with existing equipment and operating methods or in which the cost of the required equipment is relatively minor
compared to the cost of a new well; and

(ii) Through installed extraction equipment and infrastructure operational at the time
of the reserves estimate if the extraction is by means not involving a well.

Undeveloped oil and gas reserves Undeveloped oil and gas reserves are reserves of any category that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.

(i) Reserves on undrilled acreage shall be limited to those directly offsetting development spacing areas that are reasonably certain of
production when drilled, unless evidence using reliable technology exists that establishes reasonable certainty of economic producibility at greater distances.



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(ii) Undrilled locations can be classified as having undeveloped reserves only if a
development plan has been adopted indicating that they are scheduled to be drilled within five years, unless the specific circumstances, justify a longer time.

(iii) Under no circumstances shall estimates for undeveloped reserves be attributable to any acreage for which an application of fluid injection or other improved recovery technique is contemplated,
unless such techniques have been proved effective by actual projects in the same reservoir or an analogous reservoir, as defined in [section 210.410 (a) Definitions], or by other evidence using reliable technology establishing reasonable
certainty.

Primary Economic Assumptions

The following economic assumptions were used for estimating existing and future prices and costs:

Oil Prices

Prices used in this evaluation were based on local
differentials to a West Texas Intermediate (WTI) price of $61.04 per barrel. The WTI base price is the average price for WTI crude on the first of each month during 2009. Local differentials were based on the difference between the actual price
received and the WTI price on the first day of each month during 2009. The weighted average price over the lives of the properties was $60.37 per barrel.

Natural Gas Prices

Prices used in this evaluation were based on local
differentials to a Henry Hub gas price of $3.87 per million British thermal units (MMBtu). The Henry Hub base price is the average price for Henry Hub gas on the first of each month during 2009. Local differentials were based on the difference
between the actual price received and the Henry Hub price on the first day of each month during 2009. The weighted average price over the lives of the properties was $9.628 per thousand cubic feet (Mcf).



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Operating Expenses and Capital Costs

Estimates of operating expenses based on current expenses were used for the lives of the properties with no increases in the future based on
inflation. In certain cases, future expenses, either higher or lower than current expenses, may have been used because of anticipated changes in operating conditions. Future capital expenditures were estimated using 2009 values and were not adjusted
for inflation.

Abandonment Costs

Abandonment costs were provided by TransAtlantic and accepted as reasonable. These costs were estimated using 2009 values and were escalated as described above.

Taxes

TransAtlantic has represented that there are no production taxes to be paid in Turkey.

While the oil and gas
industry may be subject to regulatory changes from time to time that could affect an industry participants ability to recover its oil and gas reserves, we are not aware of any such governmental actions which would restrict the recovery of the
December 31, 2009, estimated oil and gas volumes. The reserves estimated in this report can be produced under current regulatory guidelines.



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Summary of Oil and Gas Reserves and Revenue

The estimates of net proved reserves attributable to the properties appraised, as of December 31, 2009, are summarized as follows,
expressed in thousands of barrels (Mbbl), millions of cubic feet (MMcf):



|                   |  |                         |  |               
|------------------ |  | ----------------------- |  | --------------
|                   |  | Oil andCondensate(Mbbl) |  | SalesGas(MMcf)
|                   |  |                        
|Proved Developed   |  | 5,649                   |  | 4,787         
|Proved Undeveloped |  | 4,777                   |  | 2,552         
|                   |  |                         |  |               
|                   |  |                        
|Total Proved       |  | 10,426                  |  | 7,339         

The estimated
revenue and expenditures attributable to TransAtlantics interests in the proved reserves, as of December 31, 2009, of the properties appraised under the aforementioned assumptions concerning future prices and costs are summarized as
follows:



|                                |  |                        |  |                           |  |                 |  |          
|------------------------------- |  | ---------------------- |  | ------------------------- |  | --------------- |  | ---------
|                                |  | Proved                
|                                |  | DevelopedProducing(M$) |  | DevelopedNonproducing(M$) |  | Undeveloped(M$) |  | Total(M$)
|                                |  |                        |  |                          
|Future Gross Revenue            |  | 228,143                |  | 158,747                   |  | 313,113         |  | 700,003  
|Production and Ad Valorem Taxes |  | 0                      |  | 0                         |  | 0               |  | 0        
|Operating Expenses              |  | 59,671                 |  | 24,810                    |  | 74,780          |  | 159,261  
|Capital Costs                   |  | 0                      |  | 2,625                     |  | 43,609          |  | 46,234   
|Abandonment Costs               |  | 754                    |  | 339                       |  | 819             |  | 1,912    
|Future Net Revenue*             |  | 167,718                |  | 130,973                   |  | 193,905         |  | 492,596  
|Present Worth at 10 Percent*    |  | 104,941                |  | 87,575                    |  | 119,977         |  | 312,493  

* Future income
taxes have not been taken into account in the preparation of these estimates.

In our opinion, the information relating to
estimated proved reserves, estimated future net revenue from proved reserves, and present worth of estimated future net revenue from proved reserves of oil, condensate, natural gas liquids, and gas contained in this report has been prepared in
accordance with Paragraphs 932-235-50-4, 932-235-50-6, 932-235-50-7, 932-235-50-9, 932-235-50-30, and 932-235-50-31(a), (b), and (e) of the Accounting Standards Update 932-235-50, Extractive Industries  Oil and Gas (Topic 932):
Oil and Gas Reserve Estimation and Disclosures (January 2010) of the Financial Accounting Standards Board and Rules 410(a) (1)(32) of Regulation SX and Rules 302(b), 1201, 1202(a) (1), (2), (3), (4), (8), and 1203(a)
of Regulation SK of the Securities and Exchange Commission; provided, however, future income tax expenses have not been taken into account in estimating the future net revenue and present worth values set forth herein.



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DeGolyer and MacNaughton is an independent petroleum engineering consulting firm that
has been providing petroleum consulting services throughout the world for over 70 years. DeGolyer and MacNaughton does not have any financial interest, including stock ownership, in TransAtlantic. Our fees were not contingent on the results of our
evaluation. This letter report has been prepared at the request of TransAtlantic and should not be used for purposes other than those for which it is intended. DeGolyer and MacNaughton has used all procedures and methods that it considers necessary
to prepare this report.



|       |  |  |  |  |  |                                        
|------ |  |  |  |  |  | ---------------------------------------
|       |  |  |  |  |  | Submitted,                             
|       |  |  | 
|       |  |  |  |  |  | /s/ DeGolyer and MacNaughton           
|       |  |  |  |  |  | DeGOLYER and MacNAUGHTON               
|       |  |  |  |  |  | Texas Registered Engineering Firm F-716
|       |  |  | 
|       |  |  |  |  |  | /s/ Paul J. Szatkowski, P.E.           
|       |  |  |  |  |  | Paul J. Szatkowski, P.E.               
|[SEAL] |  |  |  |  |  | Senior Vice President                  
|       |  |  |  |  |  | DeGolyer and MacNaughton               



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CERTIFICATE of QUALIFICATION

I, Paul J. Szatkowski, Petroleum Engineer with DeGolyer and MacNaughton, 5001 Spring Valley Road, Suite 800 East, Dallas, Texas, 75244 U.S.A., hereby
certify:



| | 1. | That I am a Senior Vice President with DeGolyer and MacNaughton, which company did prepare the letter report addressed to TransAtlantic dated March 2, 2010, and
that I, as Senior Vice President, was responsible for the preparation of this report.
| | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | 2. | That I attended Texas A&M University, and that I graduated with a Bachelor of Science degree in Petroleum Engineering in the year 1974; that I am a Registered
Professional Engineer in the State of Texas; that I am a member of the International Society of Petroleum Engineers and the American Association of Petroleum Geologists; and that I have in excess of 35 years of experience in the oil and gas
reservoir studies and reserves evaluations.
| | -- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



|       |  |  |  |  |  |                             
|------ |  |  |  |  |  | ----------------------------
|       |  |  |  |  |  | /s/ Paul J. Szatkowski, P.E.
|       |  |  |  |  |  | Paul J. Szatkowski, P.E.    
|[SEAL] |  |  |  |  |  | Senior Vice President       
|       |  |  |  |  |  | DeGolyer and MacNaughton