* 2009 proven finds 74.9 pct production vs 72 pct in 2008
* Wider "3P" discovery rate leaps to 157.9 pct vs 102 pct
* Deepwater drilling in 4th-qtr yields no oil finds (Recasts with context from 2008, detail, adds byline)
By Robert Campbell
MEXICO CITY, March 3 Mexico's state oil monopoly Pemex improved its exploration efforts in 2009, replacing more of its oil and gas production than in previous years, according to preliminary estimates on Wednesday.
Pemex [PEMX.UL] said it discovered enough new proven oil and gas reserves to replace 74.9 percent of its 2009 production, up from a replacement rate of 72 percent in 2008.
Mexico's proven oil reserves have fallen by more than 40 percent since 2000 due to underinvestment in exploration. Pemex has been working to improve its efforts to find more oil and gas and has targeted achieving a 100 percent reserve replacement rate by 2012.
Pemex's exploration efforts as measured by the looser definition of proven, probable and possible reserves, or 3P, was even more successful. The 3P reserve replacement rate in 2009 jumped to 157.9 percent from 102 percent in 2008.
Mexico's proven oil and gas reserves totaled 14.3 billion barrels of oil equivalent at the end of 2008. The government is expected to release official 2009 reserves data on March 18.
Mexican energy officials have pointed to the almost completely unexplored deep waters of the Gulf of Mexico as the long-term hope for Mexican oil production but Pemex has struggled to make commercial finds in the area.
The company completed five deep sea exploration wells in 2009, but only one, Leek-1, was successful and it encountered mainly natural gas, rather than the crude that Pemex wants to be discovering.
Of the other four wells, Kabilil-1 was a dry hole, Holok-1 found salt water, Etbakel-1 was a non-commercial oil find and Catamat-1 was a non-commercial gas discovery. (Reporting by Robert Campbell; Editing by Rebekah Kebede)