The Permian shale basin in the southern United States is the most prolific with output topping 1.3 million barrels per day, the Energy Department said.

Permian production increased 58 percent from 2007 to reach 1.35 million bpd last year, which represents 18 percent of total U.S. crude oil production.

In a review published Wednesday, the U.S. Energy Information Administration said the Permian basin has exceeded production from offshore Gulf of Mexico since 2013.

"The Permian Basin in Texas and New Mexico is the nation's most prolific oil producing area," EIA said in its profile.

Production from the Bakken reserve area in North Dakota is highlighted as helping push the United States to the top of the list of oil production nations. Bakken output reached 1 million bpd for the first time in April.

North Dakota is the No. 2 oil producer in the nation after Texas.

Permian is spread out over 75,000 square miles across Texas and New Mexico.

API publishes 'gold standard' of guidelines for communities hosting fracking
Washington (UPI) Jul 10, 2013 - The American Petroleum Institute released its first-ever set of guidelines aimed at directing community engagement where hydraulic fracturing is planned.

"API's community engagement guidelines will serve as a gold standard for good neighbor policies that address community concerns, enhance the long-term benefits of local development, and ensure a two-way conversation regarding mutual goals for community growth," API Director of Standards David Miller said in a statement Wednesday.

Hydraulic fracturing and horizontal drilling are two technologies used to produce oil and natural gas from shale deposits. Shale exploitation has led to exponential gains in U.S. oil and gas production, though the drilling processes, dubbed fracking, have been met with opposition from those concerned about the environmental drawbacks.

API said its new standards provide guidelines on how to conduct public meetings on safety and prepare communities for energy exploration in order to minimize interruptions.

API represents the business interests of more than 600 oil and natural gas companies.