The longtime prolifically productive Gulf of Mexico Basin appears to harbor all the makings of a seemingly inexhaustible supply of hydrocarbons.
This explains why various companies continue to acquire seismic and other data for their geoscientists to evaluate and interpret, often more than once as technology advances. The goal of these efforts is to find new oil and gas sources and to better understand already-producing sources in terms of the hydrocarbon content, the myriad trapping mechanisms and more.
“Interpretation of regional 2-D seismic data from the U.S. onshore and Mexico offshore is the framework for an integrated margin-to-margin basin evaluation,” said Brian Horn, senior vice president and chief geologist at ION.
The company has been engaged in acquiring and interpreting such a program for the past 15 years, engaging about 75 employees. It was designed as a regional endeavor from the get-go.
“These data provide unique coverage of the entire Gulf of Mexico Basin from margins to the basin, showing the deeper Mesozoic strata, the underlying basement and, in particular, the pre-salt strata offshore Mexico,” Horn said.
Analysis of the seismic character southward to the Bay of Campeche and isopach maps of the entire basin depositional systems through time provide the framework for calibrating maturation modeling and prediction of migration fairways across the GOM, along with the location of depositional systems through time, according to Horn.
“Combining these new data where basement is well imaged with gravity and magnetic data make it possible to constrain the position of the continent-ocean transitions in several areas, including the Yucatan rifted margin and the East Mexican transform margin,” he noted.
Horn will delve into many of these particulars when he takes a turn on the dais during the Discovery Thinking Forum session at the AAPG/SEG International Conference and Exhibition (ICE) in Cancun, Mexico this month.
Why the Gulf?
Likely, there are some who question the inclusion of the Gulf basin in such a forum.
Horn turns this kind of thinking upside down.
“While it’s not about a specific discovery, the intent of the talk is to emphasize that even though this is the most mature basin in the world, earth scientists continue to find significant oil accumulations,” he noted, “and there are still many things about the basin that are not understood.”
Progress is afoot given there are datasets covering the entire region that help to put plays and discoveries into the context of where they fit in the basin petroleum system.
“Now that we can at least image the basin in its entirety, we can begin to ask more salient questions about what’s left, what we should be looking for, what we have missed,” Horn said.
Think about Mexico, for example, which is a new frontier in many ways, even though a lot of the main plays have been discovered.
“In the Campeche salt basin, we know that the Tertiary plays are successful,” Horn said. “But there are things we see now with the new seismic that look like they may be a new pre-salt play, and we’re imaging those things.
“We have a much better understanding of basin tectonics now and how the Gulf opened, how it grew,” he stressed. “You really want to understand the basin as it evolved and see how it changes through time to understand where the hydrocarbons might be.”
Over the years, myriad theories and perspectives have been developed about the GOM overall, given its never-ending allure, with the major exception being when it was temporarily dubbed the “dead sea” during one of the industry’s more-infamous downturns.
The Big Picture
Don’t expect a presentation at ICE that will have all the answers in 40 minutes, Horn cautioned.
“Way more people have worked the area to a greater extent than I,” he emphasized. “This (talk) is more about what we’ve learned and where we potentially could go – and I say this with humility.
“Discovery thinking starts by understanding the entire basin, not just one discovery or field, or series of fields,” he asserted. “It’s about understanding how plays develop and what you need to know from a bottoms-up approach.
“This is the kind of thinking that will lead to future discoveries.
“You don’t find the oil on seismic lines,” he quipped.