WASHINGTON — The Trump administration said Wednesday it is moving forward on seismic surveys in the Atlantic Ocean, the first step toward offshore drilling in a region where it has been blocked for decades.

The Interior Department said it is reviewing six applications by energy companies that were rejected by the Obama administration.

Environmental groups and many East Coast lawmakers oppose the surveys, saying loud sounds from seismic air guns could hurt marine life. Some are also fearful that drilling would threaten fisheries and the tourist industry.

The oil and gas industry has pushed for the surveys, which map potential drilling sites for oil and natural gas. No surveys have been conducted in the mid- and south Atlantic regions for at least 30 years.

The regions, as defined by the Interior Department, stretch from northern Florida to Delaware. Any new drilling activity is expected to be limited to the coasts of Virginia, North and South Carolina and Georgia.

President Trump signed an executive order last month aimed at expanding drilling in the Arctic and Atlantic, part of his promise to unleash the nation’s energy reserves in an effort to reduce imports of oil.

Trump’s order reversed an action by former President Barack Obama and faces fierce opposition from environmental activists and many Democrats, who say offshore drilling harms whales, walruses and other wildlife and exacerbates global warming.

The Interior Department said in a statement that the surveys are needed to update information about the Outer Continental Shelf that was gathered more than 30 years ago, “when technology was not as advanced as today.”

In addition to providing data on potential sites for offshore oil and natural gas production, seismic surveys are also used to locate sites for offshore wind structures, pinpoint potential seafloor hazards and locate sand and gravel resources for beach restoration, the department said.

Data from seismic surveys also assists officials in determining fair market value of offshore resources.