OXY Occidental Petroleum Corporation

• 2014 year-end proved reserves of 2.82 billion BOE, an increase of nearly 3 percent
• 2014 domestic reserve replacement ratio of 266 percent and total company replacement of 174 percent
• Three-year reserve replacement ratio of 169 percent

Occidental Petroleum Corporation (NYSE:OXY) announced today that at year-end 2014, the company's preliminary worldwide proved reserves totaled 2.82 billion barrels of oil equivalent (BOE) compared to 2.74 billion BOE at the end of 2013, restated to exclude California Resources Corporation. In 2014, the company had proved reserve additions from all sources of 380 million BOE, compared to production of 218 million BOE, for a production replacement ratio of 174 percent.

The preliminary domestic proved reserves totaled 1.78 billion BOE compared to 1.67 billion BOE at the end of 2013. In 2014, the domestic operations had proved reserve additions from all sources of 308 million BOE, compared to production of 116 million BOE, for a production replacement ratio of 266 percent.

"We are pleased to have replaced 174 percent of our 2014 production largely through improved recovery and extensions and discoveries. Over the last three years, we replaced 169 percent of our production. Our 2014 program resulted in apparent finding and development costs of $16.89 per BOE. For the last three-year period, our finding and development costs averaged about $18.66 per BOE including revisions," said Stephen I. Chazen, President and Chief Executive Officer.

As of December 31, 2014, 63 percent of the company's proved reserves consisted of oil, 13 percent of NGL and 24 percent of gas. Of the total proved reserves, approximately 60 percent is in the United States and 40 percent in international locations. Approximately 70 percent of the proved reserves are developed and 30 percent are undeveloped. Total company revisions were negative 58 million BOE, which included 54 million from the write-down of Bahrain. Total company proved additions, excluding revisions, were 438 million BOE, mostly coming from improved recovery. The proved undeveloped reserves increased by 284 million BOE due to improved recovery mainly in Permian Resources. These additions were offset by transfers of 315 million BOE to proved developed, with the Al Hosn Gas Project transfer accounting for 68 percent of the total.

About Occidental Petroleum

Occidental Petroleum Corporation is an international oil and gas exploration and production company with operations in the United States, Middle East/North Africa and Latin America regions. Headquartered in Houston, Occidental is one of the largest U.S. oil and gas companies, based on equity market capitalization. Occidental’s midstream and marketing segment gathers, processes, transports, stores, purchases and markets hydrocarbons and other commodities in support of Occidental’s businesses. The company’s wholly owned subsidiary, OxyChem manufactures and markets chlor-alkali products and vinyls.

Forward-Looking Statements

Portions of this press release contain forward-looking statements and involve risks and uncertainties that could materially affect expected results of operations, liquidity, cash flows and business prospects. Actual results may differ from anticipated results, sometimes materially, and reported results should not be considered an indication of future performance. Factors that could cause results to differ include, but are not limited to: global commodity pricing fluctuations; supply and demand considerations for Occidental’s products; higher-than-expected costs; the regulatory approval environment; reorganization or restructuring of Occidental’s operations; not successfully completing, or any material delay of, field developments, expansion projects, capital expenditures, efficiency projects, acquisitions or dispositions; lower-than-expected production from development projects or acquisitions; exploration risks; general economic slowdowns domestically or internationally; political conditions and events; liability under environmental regulations including remedial actions; litigation; disruption or interruption of production or manufacturing or facility damage due to accidents, chemical releases, labor unrest, weather, natural disasters, cyber attacks or insurgent activity; failure of risk management; changes in law or regulations; or changes in tax rates. Words such as “preliminary,” “estimate,” “project,” “predict,” “will,” “would,” “should,” “could,” “may,” “might,” “anticipate,” “plan,” “intend,” “believe,” “expect,” “aim,” “goal,” “target,” “objective,” “likely” or similar expressions that convey the prospective nature of events or outcomes generally indicate forward-looking statements. You should not place undue reliance on these forward-looking statements, which speak only as of the date of this release. Unless legally required, Occidental does not undertake any obligation to update any forward-looking statements, as a result of new information, future events or otherwise. Material risks that may affect Occidental’s results of operations and financial position appear in Part I, Item 1A “Risk Factors” of the 2013 Form 10-K. Occidental posts or provides links to important information on its website at www.oxy.com.

Attachment 1                           OIL AND GAS PRELIMINARY RESERVES                 The following tables set forth Occidental's net interests in quantities of proved developed and undeveloped oil (including condensate), NGLs, natural gas and changes in such quantities. Reserves are stated net of applicable royalties. Estimated reserves include Occidental's economic interests under production-sharing contracts (PSCs) and other similar economic arrangements.   Attachment 2   OIL AND GAS PRELIMINARY RESERVES   OIL RESERVES In millions of barrels (MMbbl) United Latin Middle East/   States America North Africa Total PROVED DEVELOPED AND UNDEVELOPED RESERVES   Balance at December 31, 2011 1,019 96 386 1,501 Revisions of previous estimates (25 ) 4 (3 ) (24 ) Improved recovery 81 7 30 118 Extensions and discoveries 3 - 27 30 Purchases of proved reserves 52 - - 52 Production   (61 )   (11 )   (67 )   (139 ) Balance at December 31, 2012 1,069 96 373 1,538 Revisions of previous estimates (36 ) (5 ) 12 (29 ) Improved recovery 137 7 60 204 Extensions and discoveries 4 - 14 18 Purchases of proved reserves 25 - - 25 Sales of proved reserves (4 ) - - (4 ) Production   (64 )   (10 )   (65 )   (139 ) Balance at December 31, 2013 1,131 88 394 1,613 Revisions of previous estimates (54 ) 6 40 (8 ) Improved recovery 224 9 32 265 Extensions and discoveries 15 - 2 17 Purchases of proved reserves 33 - - 33 Sales of proved reserves (9 ) - - (9 ) Production   (67 )   (11 )   (63 )   (141 ) Balance at December 31, 2014   1,273     92     405     1,770     Proved Developed Reserves December 31, 2011 780 69 317 1,166 December 31, 2012 803 82 295 1,180 December 31, 2013 822 76 281 1,179 December 31, 2014 819 86 316 1,221     Attachment 3   OIL AND GAS PRELIMINARY RESERVES   NGL RESERVES In millions of barrels (MMbbl) United Latin Middle East/   States America North Africa Total PROVED DEVELOPED AND UNDEVELOPED RESERVES Balance at December 31, 2011 158 - 55 213 Revisions of previous estimates 15 - - 15 Improved recovery 3 - - 3 Extensions and discoveries - - 64 64 Purchases of proved reserves 1 - - 1 Production   (21 )   -     (3 )   (24 ) Balance at December 31, 2012 156 - 116 272 Revisions of previous estimates 53 - (1 ) 52 Improved recovery 9 - - 9 Extensions and discoveries - - 22 22 Purchases of proved reserves 7 - - 7 Sales of proved reserves - - - - Production   (21 )   -     (3 )   (24 ) Balance at December 31, 2013 204 - 134 338 Revisions of previous estimates 6 - 8 14 Improved recovery 37 - - 37 Extensions and discoveries 2 - - 2 Purchases of proved reserves 3 - - 3 Sales of proved reserves (10 ) - - (10 ) Production   (20 )   -     (2 )   (22 ) Balance at December 31, 2014   222     -     140     362     Proved Developed Reserves December 31, 2011 123 - 55 178 December 31, 2012 124 - 53 177 December 31, 2013 151 - 51 202 December 31, 2014 147 - 109 256       Attachment 4   OIL AND GAS PRELIMINARY RESERVES   GAS RESERVES In billions of cubic feet (Bcf) United Latin Middle East/   States America North Africa   Total PROVED DEVELOPED AND UNDEVELOPED RESERVES Balance at December 31, 2011 2,449 33 1,925 4,407 Revisions of previous estimates (581 ) - 62 (519 ) Improved recovery 207 11 34 252 Extensions and discoveries 7 - 784 791 Purchases of proved reserves 80 - - 80 Production   (207 )   (5 )   (165 )   (377 ) Balance at December 31, 2012 1,955 39 2,640 4,634 Revisions of previous estimates (46 ) (11 ) (43 ) (100 ) Improved recovery 251 1 16 268 Extensions and discoveries 13 - 232 245 Purchases of proved reserves 34 - - 34 Sales of proved reserves (2 ) - - (2 ) Production   (193 )   (5 )   (158 )   (356 ) Balance at December 31, 2013 2,012 24 2,687 4,723 Revisions of previous estimates (111 ) 3 (273 ) (381 ) Improved recovery 284 4 25 313 Extensions and discoveries 27 - 101 128 Purchases of proved reserves 46 - - 46 Sales of proved reserves (371 ) - - (371 ) Production   (173 )   (4 )   (154 )   (331 ) Balance at December 31, 2014   1,714     27     2,386     4,127     Proved Developed Reserves December 31, 2011 1,723 32 1,555 3,310 December 31, 2012 1,454 36 1,816 3,306 December 31, 2013 1,495 23 1,684 3,202 December 31, 2014 1,128 26 1,915 3,069       Attachment 5   OIL AND GAS PRELIMINARY RESERVES   TOTAL RESERVES In millions of BOE (MMBOE) (a) United Latin Middle East/   States America North Africa   Total PROVED DEVELOPED AND UNDEVELOPED RESERVES Balance at December 31, 2011 1,585 101 762 2,448 Revisions of previous estimates (107 ) 4 7 (96 ) Improved recovery 119 9 36 164 Extensions and discoveries 4 - 222 226 Purchases of proved reserves 66 - - 66 Production   (116 )   (12 )   (98 )   (226 ) Balance at December 31, 2012 1,551 102 929 2,582 Revisions of previous estimates 10 (7 ) 4 7 Improved recovery 188 8 63 259 Extensions and discoveries 6 - 74 80 Purchases of proved reserves 37 - - 37 Sales of proved reserves (5 ) - - (5 ) Production   (117 )   (11 )   (94 )   (222 ) Balance at December 31, 2013 1,670 92 976 2,738 Revisions of previous estimates (67 ) 6 3 (58 ) Improved recovery 310 9 35 354 Extensions and discoveries 22 - 19 41 Purchases of proved reserves 43 - - 43 Sales of proved reserves (81 ) - - (81 ) Production   (116 )   (11 )   (91 )   (218 ) Balance at December 31, 2014   1,781     96     942     2,819     Proved Developed Reserves December 31, 2011 1,190 74 631 1,895 December 31, 2012 1,169 88 651 1,908 December 31, 2013 1,222 80 613 1,915 December 31, 2014 1,154 90 744 1,988   (a) Natural gas volumes have been converted to barrels of oil equivalent (BOE) based on energy content of six thousand cubic feet (Mcf) of gas to one barrel of oil.         Attachment 6   PRELIMINARY COSTS INCURRED ($ Millions)   Costs incurred in oil and gas property acquisition, exploration and development activities, whether capitalized or expensed, were as follows:     United Latin Middle East/ States America North Africa   Total For the Year Ended December 31, 2014 Property acquisition costs Proved properties $ 771 $ - $ - $ 771 Unproved properties 842 - - 842 Exploration costs 379 4 180 563 Development costs   3,665     305     2,138     6,108   Costs Incurred $ 5,657   $ 309   $ 2,318   $ 8,284     For the Year Ended December 31, 2013 Property acquisition costs Proved properties $ 343 $ - $ - $ 343 Unproved properties 151 - - 151 Exploration costs 293 11 79 383 Development costs   2,659     329     2,117     5,105   Costs Incurred $ 3,446   $ 340   $ 2,196   $ 5,982     For the Year Ended December 31, 2012 Property acquisition costs Proved properties $ 1,333 $ - $ 14 $ 1,347 Unproved properties 573 - - 573 Exploration costs 379 1 114 494 Development costs   3,271     304     2,025     5,600   Costs Incurred $ 5,556   $ 305   $ 2,153   $ 8,014         Attachment 7   PRELIMINARY MULTI-YEAR DATA   WORLDWIDE 2012 2013 2014 3-Yr Average Reserves Replacement (Million BOE) Revisions (96 ) 7 (58 ) (49 ) Improved recovery 164 259 354 259 Extensions and discoveries   226     80     41     116   Organic without revisions (A)   390     339     395     375   Organic with revisions (B) 294 346 337 326 Purchases   66     37     43     49   Total reserve additions (C)   360     383     380     375   Production (D) 226 222 218 222   Costs Incurred ($ Millions) Acquisitions 1,920 494 1,613 1,342 Exploration costs 494 383 563 480 Development costs   5,600     5,105     6,108     5,604   Organic (E)   6,094     5,488     6,671     6,084   Total costs incurred (F)   8,014     5,982     8,284     7,426     Finding & Development Costs per BOE Organic without revisions (E) / (A) $ 15.63 $ 16.19 $ 16.89 $ 16.22 Organic with revisions (E) / (B) $ 20.73 $ 15.86 $ 19.80 $ 18.66 All-in (F) / (C) $ 22.26 $ 15.62 $ 21.80 $ 19.80   Reserve Replacement Ratio Organic without revisions (A) / (D) 173 % 153 % 181 % 169 % Organic with revisions (B) / (D) 130 % 156 % 155 % 147 % All-in (C) / (D)   159 %   173 %   174 %   169 %     UNITED STATES 2012 2013 2014 3-Yr Average Reserves Replacement (Million BOE) Revisions (107 ) 10 (67 ) (55 ) Improved recovery 119 188 310 206 Extensions and discoveries   4     6     22     11   Organic without revisions (A)   123     194     332     217   Organic with revisions (B) 16 204 265 162 Purchases   66     37     43     49   Total reserve additions (C)   82     241     308     211   Production (D) 116 117 116 116   Costs Incurred ($ Millions) Acquisitions 1,906 494 1,613 1,338 Exploration costs 379 293 379 350 Development costs   3,271     2,659     3,665     3,198   Organic (E)   3,650     2,952     4,044     3,548   Total costs incurred (F)   5,556     3,446     5,657     4,886     Finding & Development Costs per BOE Organic without revisions (E) / (A) $ 29.67 $ 15.22 $ 12.18 $ 16.35 Organic with revisions (E) / (B) $ 228.13 $ 14.47 $ 15.26 $ 21.90 All-in (F) / (C) $ 67.76 $ 14.30 $ 18.37 $ 23.16   Reserve Replacement Ratio Organic without revisions (A) / (D) 106 % 166 % 286 % 187 % Organic with revisions (B) / (D) 14 % 174 % 228 % 140 % All-in (C) / (D) 71 % 206 % 266 % 182 %

Occidental Petroleum CorporationMedia:Melissa E. Schoeb713-366-5615melissa_schoeb@oxy.comorInvestors:Christopher M. Degner212-603-8111christopher_degner@oxy.comOn the web: www.oxy.com