Oil prices fell to their lowest levels in over a year Tuesday, continuing a precipitous decline spurred by economic uncertainty and growing global supplies.

West Texas Intermediate, the U.S. benchmark, slid 7.3% to $46.24 a barrel on Tuesday, a nearly 40% decline from the roughly four-year highs reached at the start of October. Investors have grown increasingly jittery that slowing global growth will weigh on fuel demand, while major oil exporters have failed to alleviate concerns about an oversupplied market.

Oil’s...