Updated Seismic Data Needed For OCS

The first seismic surveys of the Atlantic Outer Continental Shelf (OCS) since 1988 could happen in the next two years ­– if the Bureau of Ocean Energy Management (BOEM) finalizes the required environmental impact statement (EIS) in the next few months.

The next step would be for BOEM to issue permits for the seismic surveys and other geological and geophysical activities in support of oil and gas exploration and development, renewable energy and marine minerals in the Mid- and South-Atlantic planning areas.

This process started with nine applications for geophysical surveys submitted from 2005 to 2009, and BOEM’s 2009 announcement of its intent to prepare an EIS.

This is an important step for the future of Atlantic offshore oil and gas production. Unfortunately, the EIS, which was started in 2009, has been sufficiently delayed that seismic data will not be available in 2014, as BOEM starts development of its next five-year OCS leasing plan.

The next five-year plan can consider opening Atlantic offshore tracks to leasing without the seismic data, but seismic surveys and geologic assessments must be completed before there are any lease sales.

The seismic surveys, however, do not assure that the South-, Mid- or North Atlantic OCS areas will be included in the 2017-22 five-year OCS leasing plan or that leasing will occur.

The U.S. Atlantic OCS was under a variety of congressional or executive branch moratoria between 1982 and 2008, which prohibited any geological or geophysical studies. (There also was a six-month moratorium on deepwater drilling instituted in response to the Macondo well blowout.)

Existing Seismic Data

Seismic surveys were conducted in the Atlantic from 1966 to 1988, before the development of 3-D seismic. The publically available Atlantic OCS seismic data includes 11 surveys made up of 1,132 track lines that cover 56,493 kilometers, which are available from the U.S. Geological Survey.

The past moratoria have struck some as illogical when Canada has a thriving Atlantic oil and gas industry. Looking specifically at seismic surveys, Shell completed a large 3-D survey this past summer and fall in deep water about 200 miles off the coast of Nova Scotia.

Recently, a representative of the Canadian Association of Petroleum Producers reported on Canadian offshore activity to a House Natural Resources Committee, Subcommittee on Energy and Mineral Resources hearing.

Seismic surveys have been conducted offshore Canada for decades, and, as in the United States, Canadian seismic surveys are required to avoid marine mammals and sea turtles and to mitigate impacts to marine organisms and fishing vessels.

Potential Resource Volumes

BOEM released its “Assessment of Undiscovered Technically Recoverable Oil and Gas Resources of the Nation’s Outer Continental Shelf” in 2011. The assessment estimates that 3.3 billion barrels of oil (Bbo) and 31.28 trillion cubic feet (tcf) of gas are in the Atlantic OCS, excluding Florida.

By area, the estimated technically recoverable resources are:

  • North Atlantic – 1.35 Bbo and 9.87 tcf of gas.
  • Mid-Atlantic – 1.42 Bbo and 19.36 tcf of gas.
  • South Atlantic – 0.53 Bbo and 2.04 tcf of gas.

Geophysicists point out that these volumes, based on outdated geophysical and sparse well data, are bound to be exceptionally low.

(The potential for greater resources is suggested by the fact that the Gulf of Mexico resource estimate grew five-fold from 1987 to 2011 assessments, based on improved seismic and drilling.)

Regulators and policy makers, as well as energy developers and consumers, expect to benefit from improved understanding of the resource base.

Environmental Concerns

Many environmental organizations are opposed to allowing seismic surveys in the Atlantic because of potential harm to marine organisms, especially endangered whales and sea turtles.

Others oppose the seismic surveys because they may facilitate future oil and gas drilling and fossil energy consumption.

BOEM reports that it has spent $40 million on research into the impact of seismic surveys on marine life, and has consulted with other regulatory agencies such as the National Marine Fisheries Service to assure the planned surveys comply with the Marine Mammal Protection Act.

The mitigation measures proposed by BOEM would exclude the use of air guns in right whale migration areas from mid-November through mid-April, and in waters near sea turtle nesting areas in Florida during nesting season.

Visual monitoring for marine mammals near the survey vessels would also be required.

Congressional Interest

At the House hearing, a member of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling stated that opening the Atlantic should be delayed until Congress takes the actions recommended by the Commission to improve offshore safety. An example would be modifying the Outer Continental Shelf Lands Act to increase liability amounts and provide whistleblower protections.

Congress, however, has no plans to consider legislation on offshore safety regulations.

Members of Congress have introduced several bills that would require BOEM to permit seismic testing in the Atlantic OCS as part of other changes to open the Atlantic OCS to drilling. None of these bills is expected to become law.

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Policy Watch

Policy Watch - Edie Allison
Edie Allison began as the Director of the AAPG Geoscience and Energy Office in Washington D.C. in 2012.

Policy Watch

Policy Watch is a monthly column of the EXPLORER written by the director of AAPG's  Geoscience and Energy Office in Washington, D.C. *The first article appeared in February 2006 under the name "Washington Watch" and the column name was changed to "Policy Watch" in January 2013 to broaden the subject matter to a more global view.

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