Crude oil prices continued their slow fade Tuesday even as U.S. data show evidence the bear market had an impact on the production behind recent market trends.

The price for Brent, the global benchmark, slid about 1.3 percent from Monday's close to trade near $57.70 per barrel for the April contract early in Tuesday trading. Brent hit a low mark of around $45.13 per barrel mid January and climbed 37 percent by late February. The rally, however, ran out of steam in March, with Brent crude oil prices down about 5.3 percent since the start of the month.

Crude oil prices entered a bear market in June as markets swung toward the supply side in response to gains in U.S. oil production. Prices had dipped to the point that most major oil companies were cutting back on revenue streams for exploration and production, with rig activity in the Bakken oil reserve area of North Dakota falling to a historic low.

Data in a drilling productivity report from the U.S. Energy Information Administration finds net production from key shale basins in the United States may slow down in April. Of the seven shale basins reviewed, only the Permian shale in western Texas shows a projected gain in April.

Those seven shale basins, located largely in the central United States, accounted for more than 90 percent of oil production growth from 2011-13, EIA said.

A November decision from members of the Organization of Petroleum Exporting Countries to keep production static despite sliding oil prices was seen as an effort to sideline shale, where production is at times more expensive than in conventional oil reserves.

The price for West Texas Intermediate crude oil, the U.S. benchmark, pulled further away from Brent, dropping 1.5 percent from the close Monday to $49.22. WTI prices since the beginning of the month are relatively stable.