There are approximately 90.55 billion barrels of undiscovered technically recoverable oil and a mean of 327.58 trillion cubic feet of undiscovered technically recoverable natural gas in the federal outer continental shelf of the United States.
That’s according to a report issued by the United States Bureau of Ocean Energy Management. The outer continental shelf of the United States includes 26 planning areas from the North Atlantic region all the way to the north shore of Alaska.
The exploration possibilities of all that, if not endless, are pretty encouraging.
And those possibilities will be discussed in an oral presentation at this year’s AAPG International Conference and Exhibition in Cape Town, South Africa.
Play-based Methodology
“The methodology used,” said Matt Frye, who will be among those leading the discussion, “is suitable for both conceptual plays where there is little specific information available and for developed plays where considerable information from discovered oil and gas fields is available.”
Frye is chief of BOEM’s Resource Evaluation Division.
This BOEM assessment report – the last full version came out in 2016, but it was updated earlier this year – covers crude oil, natural gas liquids (condensate) and natural gas that exist in conventional reservoirs and are producible with conventional recovery techniques. Specifically, crude oil and condensate are reported jointly as oil; associated and non-associated gas are reported as gas. BOEM, which is part of the Department of Interior, assesses the undiscovered technically recoverable oil and gas resources, using a play-based assessment, is completed every five years.
“This play-based approach,” Frye said, “provides a strong relationship between information derived from oil and gas exploration activities and the geologic model developed by the assessment team.”
“Where there isn’t much specific information,” Frye said, “analog plays are developed with a subjective approach to cover the range of uncertainties associated with these plays.” Where these mature areas have ample data – such as the Gulf of Mexico and southern California – geologic plays are analyzed by combining the subjective methodology utilizing historical trends with a discovery-based approach to account for the existing discovered pools.
The estimates of undiscovered recoverable resources are presented in two categories: undiscovered technically recoverable resources and undiscovered economically recoverable resources, or UTRR and UERR, respectively.
Specifically, delving into the numbers and looking at the map, the most dramatic changed occurred in Alaska, where the UERR gas resources declined. Frye said this is due to the implementation of an increased tariff required by changes in the presumed delivery of gas via LNG tanker systems. As for oil, specifically in the Beaufort Region, Frye said, “We noticed an increase of about 1 percent.”
That translates into about 530 million more barrels of oil.
The Gulf of Mexico was another region that experienced a fairly significant change. While the UTRR mean estimate for oil remained statistically unchanged, estimates for gas decreased approximately 35 percent, which is significant. Frye said the decrease here is attributed to a refinement of field size distributions for geologic plays in shallow water that better represents our understanding of recent exploratory well results, recently discovered gas fields, and the range of prospect sizes that have received bids in recent Gulf of Mexico Lease Sales.
In other areas, in the Pacific OCS Region mean UTRR estimates remain unchanged for both oil and natural gas when compared to the previous assessments. In the Atlantic OCS, UERR gas volumes are down slightly from 2011, which is due largely to an improved understanding of potential reservoir performance.
Probabilistic Approach
The BOEM is charged with overseeing the energy and mineral resources found on the OCS. It does not include quantities of hydrocarbon resources that could be recovered from known and future fields by enhanced recovery techniques, nor does it consider methane hydrates, gas in geo-pressured brines or oil and natural gas that may be present in insufficient quantities or quality (low permeability “tight” reservoirs) to be produced by conventional recovery techniques.
Further, the BOEM assessment model utilizes a probabilistic approach to account for the inherent uncertainties associated with an assessment of undiscovered resources.
All this data, available at BOEM.gov, can provide valuable information to exploration companies, even if the data has to be tweaked for changes in industry, environmental concerns, and economic realities.
Frye said, while the data is the starting point, BOEM gears the information to unpredictability of the market, adding that the purpose of the report and of the presentation is to provide the information needed to make those necessary exploration decisions.
“I can tell you we use different pricing scenarios to determine future energy prices.”
BOEM, for example, uses price parameters that range from $30-220 per barrel in assessing potential exploration.
He said that, while he’s not in the business of prognostications, much less predicting the best places on the shelf to explore, he’s “optimistic about the large volumes of undiscovered resources that are on our outer continental shelf.”