ExxonMobil Corp. in 2012 replaced 115% of its production, which included 56% of natural gas output, by adding proved reserves totaling 1.8 billion boe, the super major said last week.

At the end of 2012 proved reserves totaled 25.2 billion boe, 49% weighted to natural gas and 51% to liquids. Proved reserves are the reserves that can be produced although they may be hampered by transportation access or other difficulties. The proved reserves base, or reserves that are immediately available for sale, climbed to 24.9 billion boe, of which 51% was natural gas and 49% was liquids.

“ExxonMobil’s industry-leading record of long-term reserves replacement is a result of our strategic focus on quality resource capture, disciplined investment and excellence in project execution,” said CEO Rex W. Tillerson. “Replacing production with new sources of oil and gas enables ExxonMobil to develop new supplies of energy that will be critical to support future demand, economic growth and improved living standards.”

Liquids output last year surpassed natural gas additions. ExxonMobil added 1.8 billion boe to its proved reserves base in 2011, replacing 107% of production. Proved reserves at the end of 2011 had increased to 24.9 billion boe, weighted 51% to natural gas and 49% to liquids.

North America’s onshore was credited with lifting the reserves. Additions in 2012 from the liquids-rich Woodford and Bakken shales totaled almost 750 million boe. Canadian additions added more than 600 million boe. Other additions were made in Australia, Angola and Kazakhstan.

Natural gas proved reserves climbed to more than 400 million boe, a 56% replacement ratio. Liquid additions, meanwhile, rose to 1.4 billion bbl, or 174% of output. Excluding the impact of asset sales, reserves additions in 2012 replaced 124% of output.

Last year was the 19th in a row that the Irving, TX-based producer replaced more than 100% of its output. The average replacement ratio over the past 10 years, which is considered a better indicator of reserves performance because of the long-term nature of the industry, was 121%. Natural gas replacement averaged 145% over the period while liquids replacement averaged 102%. ExxonMobil’s reserves life at current production rates is 16 years.

ExxonMobil in 2012 added 4 billion boe to its resource base, “driven primarily by resource additions in the United States and Canada, as well as Romania, Tanzania, Nigeria, Australia and Papua New Guinea,” the company said. “Additions include continued success in by-the-bit exploration discoveries, undeveloped resource additions and strategic acquisitions.

“In addition, discovery and delineation of North American unconventional assets contributed to the resource base. Overall, the corporation’s resource base totaled 87 billion boe at year-end 2012, taking into account field revisions, production, and asset sales. The resource base includes proved reserves, plus other discovered resources that are expected to be ultimately recovered.”

The proved reserves for 2009 and later are based on current Securities and Exchange Commission (SEC) definitions, but for years prior, the volumes were determined on bases that differed from definitions that were in effect at the time. Oilsands and equity company reserves weren’t included in reserves estimates before 2009.

©Copyright 2013Intelligence Press Inc. All rights reserved. The preceding news reportmay not be republished or redistributed, in whole or in part, in anyform, without prior written consent of Intelligence Press, Inc.