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By David Alire Garcia
MEXICO CITY, Dec 5 (Reuters) - A long-awaited auction ofMexico's untapped deep water oil fields on Monday has beenfueled by a nearly $3 billion boom in geological data mappingalmost inaccessible deposits to open up what the industry seesas the world's "last great proven frontier."
The data rush of the past two years by many top geophysicalcompanies has sparked some of the biggest imaging projects everfor technology also used to hunt for the ruins of ancientcivilizations and explain the fate of the dinosaurs.
"What they're doing is literally rewriting the geologicalmodel of the Gulf of Mexico," Juan Carlos Zepeda, head of thenational hydrocarbons commission (CNH), Mexico's oil regulator,said ahead of Monday's deep water auctions where the likes ofChevron and BP are expected to participate.
Aside from more than $2 billion invested since 2015, thecompanies have already raked in data sales of $520 million,Zepeda said.
The data bonanza has been an early success of a 2013 energyreform that ended the 75-year old monopoly of Mexican state oilcompany Pemex in a bid to reverse a 1.2 million barrel per day(bpd) slide in crude production over the past dozen years.
Crude output on the U.S. side of the Gulf of Mexico isforecast to hit a record 1.79 million bpd next year. Mexico hasyet to sell a single deep water barrel.
The auction of a total of 11 projects could attractinvestment in the tens of billions of dollars over the lifetimeof the contracts, although the first new streams of oil output,expected from Pemex's deep water Trion project, is not expecteduntil 2022 at the earliest.
The latest geological surveys come from shooting electronicand sound waves deep into the sea floor, which bounce back andare collected by sensors. The data is then processed andre-processed by some of the world's most powerfulsupercomputers.
They yield detailed models of rock layers dating backmillions of years that help oil majors avoid dry wells, a vitalstep at a time of depressed crude prices given that a singledeep water well in the Gulf can cost $200 million.
"The competition has been fierce," said Karim Lassel,country manager for French geophysical firm CGG, which obtainedfive seismic permits from the CNH over the past couple years.
CGG has been mapping Mexican rock formations for 30 years,mostly as a Pemex contractor, having acquired all of thecompany's data for its Perdido Fold Belt acreage, where fivepotentially lucrative projects are up for grabs on Monday.
"I think the deep water Mexico opportunity is one of thegreatest opportunities at the moment globally," said Lassel.
SALT AND DINOSAURS
In the past two years, fleets of boats pulling miles-longfloating cables dotted with sensors have crisscrossed Mexico'sGulf waters numerous times, teasing out secrets far below.
One survey by U.S. oil services firm Schlumberger covered anarea nearly the size of Ireland in just one year with itslargest-ever 3D wide-azimuth mapping project.
It explored the Salina, or salt, basin in the Gulf'ssouthern waters, where six blocks are up for auction.
Salt structures are especially promising for oil explorersbecause they often seal off oil deposits.
Another survey, by Norway's TGS, recently finished thelargest-ever 2D survey done at one time, an 18-month projectthat mapped all of Mexico's Gulf waters using five ships pulling7-mile-long (12 km) sensor-studded cables.
"Geology does not stop at the border," said TGS executiveWill Ashby.
The TGS survey can be merged with well-known deep watertrends on the U.S. side of the Gulf, a first for the industry.
The same type of data-gathering has also been applied for aless commercial end: confirming the asteroid strike 65 millionyears ago just off Mexico's Yucatan peninsula that killed offthe dinosaurs and most life on earth.
The first evidence of the 110-mile (176-km) wide crater theasteroid left behind was produced in the 1970s when Pemexengineers extracted drill cores from an unusual circularstructure they found in rock dating back to the final dinosaurera.
Since then, nearby discoveries in shallow waters have beenthe mainstay of Pemex's crude production, contributing nearly 80percent of the company's 2.1 million bpd of current output.
While oil companies continue to rely on better data to makeincreasingly expensive decisions, there is still no guarantee awell will produce.
"No matter how far technology has reached," said the CNH'sZepeda, "you cannot be sure what is down there until you drill."
(Editing by Dave Graham and Alan Crosby)
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