Innumerable geoscientists worldwide are familiar with the AAPG Giant Oil Fields publications.
The legendary, now-deceased oilman and AAPG Honorary member Michel “Mike” Halbouty kicked off the series in 1970 with AAPG Memoir 14, “Geology of Giant Petroleum Fields.”
Never one to rest on his laurels, Halbouty followed up on the initial publication with three additional volumes. The last, titled “Giant Oil and Gas Fields of the Decade 1990-1999,” was completed in 2000.
“He had remarkable leadership skills and the vision to identify the most important things,” said AAPG Honorary member Charles Sternbach. “He was my personal mentor and hero, and the Memoir series is his legacy.”
Fear not, the series continues.
Sternbach and AAPG member Robert Merrill are spearheading the effort to compile “Giant Oil and Gas Fields of the Decade 2000-2010.” Also playing a key role in the project is AAPG Honorary member Mike Horn.
The end product will be a compilation of papers covering fields in areas around the globe.
Since 2000, 168 fields have been discovered containing 500 MMBOE EUR, which geoscientists in general label “giant.” They include both conventional and unconventional.
“Our target is to include a representative number of fields of different play types in this 168-field population,” Merrill said. “We’ll go below 500 million barrels if there is a particular field that opens up a brand new play.”
The initial goal was to include perhaps 15 to 20 fields. The dedicated team now has 14 definite commitments for field papers – including one from Bill Zagorski on the Marcellus Shale, and from recently named AAPG Outstanding Explorer of the Year Hans Ronnevik – and is awaiting response to invitations issued to other potential contributors.
Others who would like to suggest or make a contribution are welcome to contact the team as well; the deadline is Feb. 15.
Already the potential lineup is global in scale.
“When you look at areas, we have commitments probably from India, Iraq, Norway, China, Brazil, the U.S. Gulf of Mexico, Ghana and Mozambique,” Merrill noted.
Seeking Significance
And, yes, the project team said, unconventionals also will be included in the new volume, with the Marcellus and Bakken shale plays on the “for sure” list at press time, accompanied by such conventional barnburners as the Taq Taq field in Iraq and Johan Sverdrup offshore Norway in the North Sea.
“The purpose of these papers is so the reader can gain ideas and understand what are the controlling factors of these fields, what controls petroleum generation, migration and accumulation,” Merrill said. “If we can understand giant fields, this gives us ideas to go forward that might allow us to look at a basin or area slightly differently.
“As geoscientists, we need to understand what’s common in these different accumulations,” he continued. “And even more importantly, what is different in each accumulation, because it’s the unusual thing in a field that may contain the key to the next (one) we find.”
In other words, the importance of examining the out-of-the-ordinary aspects of a giant field can’t be overemphasized. This can be the pathway toward creative ideas that could lead to another discovery.
Merrill cited some conventional field examples, including a source rock field discovery offshore Egypt.
“The important thing about this discovery is it showed a source rock older than anything others had postulated before,” he emphasized. “So here we have a new source rock in the eastern Mediterranean Basin that becomes very important because we now have the potential to find other accumulations there.
“Another area of the world with significant discoveries where people didn’t realize there was source rock is offshore Madagascar,” he said. “There are a number of giant gas fields there because somebody finally proved up the source rock; this is another province that came to fruition in the 2000s decade.
“Also in this same decade, there’s deepwater offshore Brazil where people found there were reservoirs, source material and we have some giant fields.”
In your quest for the unusual, don’t overlook the standard must-haves that are common to all fields.
“In all instances you have to have a trap, a reservoir, a source rock,” Merrill emphasized. “Also there’s the timing – the generation and migration has to be right.
“If we lump petroleum system factors together in giant fields, it helps us to discover new oil and gas accumulations.”